Merge from Google internal for 3.4 release

21 files changed, 5724 insertions, 0 deletions

diff --git a/js/compatibility_tests/v3.1.0/binary/arith_test.js b/js/compatibility_tests/v3.1.0/binary/arith_test.js
new file mode 100644
index 00000000..89796bf7
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/binary/arith_test.js
@@ -0,0 +1,355 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/**
+ * @fileoverview Test cases for Int64-manipulation functions.
+ *
+ * Test suite is written using Jasmine -- see http://jasmine.github.io/
+ *
+ * @author cfallin@google.com (Chris Fallin)
+ */
+
+goog.require('goog.testing.asserts');
+goog.require('jspb.arith.Int64');
+goog.require('jspb.arith.UInt64');
+
+
+describe('binaryArithTest', function() {
+  /**
+   * Tests comparison operations.
+   */
+  it('testCompare', function() {
+    var a = new jspb.arith.UInt64(1234, 5678);
+    var b = new jspb.arith.UInt64(1234, 5678);
+    assertEquals(a.cmp(b), 0);
+    assertEquals(b.cmp(a), 0);
+    b.lo -= 1;
+    assertEquals(a.cmp(b), 1);
+    assertEquals(b.cmp(a), -1);
+    b.lo += 2;
+    assertEquals(a.cmp(b), -1);
+    assertEquals(b.cmp(a), 1);
+    b.lo = a.lo;
+    b.hi = a.hi - 1;
+    assertEquals(a.cmp(b), 1);
+    assertEquals(b.cmp(a), -1);
+
+    assertEquals(a.zero(), false);
+    assertEquals(a.msb(), false);
+    assertEquals(a.lsb(), false);
+    a.hi = 0;
+    a.lo = 0;
+    assertEquals(a.zero(), true);
+    a.hi = 0x80000000;
+    assertEquals(a.zero(), false);
+    assertEquals(a.msb(), true);
+    a.lo = 0x00000001;
+    assertEquals(a.lsb(), true);
+  });
+
+
+  /**
+   * Tests shifts.
+   */
+  it('testShifts', function() {
+    var a = new jspb.arith.UInt64(1, 0);
+    assertEquals(a.lo, 1);
+    assertEquals(a.hi, 0);
+    var orig = a;
+    a = a.leftShift();
+    assertEquals(orig.lo, 1);  // original unmodified.
+    assertEquals(orig.hi, 0);
+    assertEquals(a.lo, 2);
+    assertEquals(a.hi, 0);
+    a = a.leftShift();
+    assertEquals(a.lo, 4);
+    assertEquals(a.hi, 0);
+    for (var i = 0; i < 29; i++) {
+      a = a.leftShift();
+    }
+    assertEquals(a.lo, 0x80000000);
+    assertEquals(a.hi, 0);
+    a = a.leftShift();
+    assertEquals(a.lo, 0);
+    assertEquals(a.hi, 1);
+    a = a.leftShift();
+    assertEquals(a.lo, 0);
+    assertEquals(a.hi, 2);
+    a = a.rightShift();
+    a = a.rightShift();
+    assertEquals(a.lo, 0x80000000);
+    assertEquals(a.hi, 0);
+    a = a.rightShift();
+    assertEquals(a.lo, 0x40000000);
+    assertEquals(a.hi, 0);
+  });
+
+
+  /**
+   * Tests additions.
+   */
+  it('testAdd', function() {
+    var a = new jspb.arith.UInt64(/* lo = */ 0x89abcdef,
+                                         /* hi = */ 0x01234567);
+    var b = new jspb.arith.UInt64(/* lo = */ 0xff52ab91,
+                                         /* hi = */ 0x92fa2123);
+    // Addition with carry.
+    var c = a.add(b);
+    assertEquals(a.lo, 0x89abcdef);  // originals unmodified.
+    assertEquals(a.hi, 0x01234567);
+    assertEquals(b.lo, 0xff52ab91);
+    assertEquals(b.hi, 0x92fa2123);
+    assertEquals(c.lo, 0x88fe7980);
+    assertEquals(c.hi, 0x941d668b);
+
+    // Simple addition without carry.
+    a.lo = 2;
+    a.hi = 0;
+    b.lo = 3;
+    b.hi = 0;
+    c = a.add(b);
+    assertEquals(c.lo, 5);
+    assertEquals(c.hi, 0);
+  });
+
+
+  /**
+   * Test subtractions.
+   */
+  it('testSub', function() {
+    var kLength = 10;
+    var hiValues = [0x1682ef32,
+                    0x583902f7,
+                    0xb62f5955,
+                    0x6ea99bbf,
+                    0x25a39c20,
+                    0x0700a08b,
+                    0x00f7304d,
+                    0x91a5b5af,
+                    0x89077fd2,
+                    0xe09e347c];
+    var loValues = [0xe1538b18,
+                    0xbeacd556,
+                    0x74100758,
+                    0x96e3cb26,
+                    0x56c37c3f,
+                    0xe00b3f7d,
+                    0x859f25d7,
+                    0xc2ee614a,
+                    0xe1d21cd7,
+                    0x30aae6a4];
+    for (var i = 0; i < kLength; i++) {
+      for (var j = 0; j < kLength; j++) {
+        var a = new jspb.arith.UInt64(loValues[i], hiValues[j]);
+        var b = new jspb.arith.UInt64(loValues[j], hiValues[i]);
+        var c = a.add(b).sub(b);
+        assertEquals(c.hi, a.hi);
+        assertEquals(c.lo, a.lo);
+      }
+    }
+  });
+
+
+  /**
+   * Tests 32-by-32 multiplication.
+   */
+  it('testMul32x32', function() {
+    var testData = [
+      // a        b          low(a*b)   high(a*b)
+      [0xc0abe2f8, 0x1607898a, 0x5de711b0, 0x109471b8],
+      [0x915eb3cb, 0x4fb66d0e, 0xbd0d441a, 0x2d43d0bc],
+      [0xfe4efe70, 0x80b48c37, 0xbcddea10, 0x7fdada0c],
+      [0xe222fd4a, 0xe43d524a, 0xd5e0eb64, 0xc99d549c],
+      [0xd171f469, 0xb94ebd01, 0x4be17969, 0x979bc4fa],
+      [0x829cc1df, 0xe2598b38, 0xf4157dc8, 0x737c12ad],
+      [0xf10c3767, 0x8382881e, 0x942b3612, 0x7bd428b8],
+      [0xb0f6dd24, 0x232597e1, 0x079c98a4, 0x184bbce7],
+      [0xfcdb05a7, 0x902f55bc, 0x636199a4, 0x8e69f412],
+      [0x0dd0bfa9, 0x916e27b1, 0x6e2542d9, 0x07d92e65]
+    ];
+
+    for (var i = 0; i < testData.length; i++) {
+      var a = testData[i][0] >>> 0;
+      var b = testData[i][1] >>> 0;
+      var cLow = testData[i][2] >>> 0;
+      var cHigh = testData[i][3] >>> 0;
+      var c = jspb.arith.UInt64.mul32x32(a, b);
+      assertEquals(c.lo, cLow);
+      assertEquals(c.hi, cHigh);
+    }
+  });
+
+
+  /**
+   * Tests 64-by-32 multiplication.
+   */
+  it('testMul', function() {
+    // 64x32 bits produces 96 bits of product. The multiplication function under
+    // test truncates the top 32 bits, so we compare against a 64-bit expected
+    // product.
+    var testData = [
+      // low(a)   high(a)               low(a*b)   high(a*b)
+      [0xec10955b, 0x360eb168, 0x4b7f3f5b, 0xbfcb7c59, 0x9517da5f],
+      [0x42b000fc, 0x9d101642, 0x6fa1ab72, 0x2584c438, 0x6a9e6d2b],
+      [0xf42d4fb4, 0xae366403, 0xa65a1000, 0x92434000, 0x1ff978df],
+      [0x17e2f56b, 0x25487693, 0xf13f98c7, 0x73794e2d, 0xa96b0c6a],
+      [0x492f241f, 0x76c0eb67, 0x7377ac44, 0xd4336c3c, 0xfc4b1ebe],
+      [0xd6b92321, 0xe184fa48, 0xd6e76904, 0x93141584, 0xcbf44da1],
+      [0x4bf007ea, 0x968c0a9e, 0xf5e4026a, 0x4fdb1ae4, 0x61b9fb7d],
+      [0x10a83be7, 0x2d685ba6, 0xc9e5fb7f, 0x2ad43499, 0x3742473d],
+      [0x2f261829, 0x1aca681a, 0x3d3494e3, 0x8213205b, 0x283719f8],
+      [0xe4f2ce21, 0x2e74b7bd, 0xd801b38b, 0xbc17feeb, 0xc6c44e0f]
+    ];
+
+    for (var i = 0; i < testData.length; i++) {
+      var a = new jspb.arith.UInt64(testData[i][0], testData[i][1]);
+      var prod = a.mul(testData[i][2]);
+      assertEquals(prod.lo, testData[i][3]);
+      assertEquals(prod.hi, testData[i][4]);
+    }
+  });
+
+
+  /**
+   * Tests 64-div-by-32 division.
+   */
+  it('testDiv', function() {
+    // Compute a/b, yielding quot = a/b and rem = a%b.
+    var testData = [
+      // --- divisors in (0, 2^32-1) to test full divisor range
+      // low(a)   high(a)    b          low(quot)  high(quot) rem
+      [0x712443f1, 0xe85cefcc, 0xc1a7050b, 0x332c79ad, 0x00000001, 0x92ffa882],
+      [0x11912915, 0xb2699eb5, 0x30467cbe, 0xb21b4be4, 0x00000003, 0x283465dd],
+      [0x0d917982, 0x201f2a6e, 0x3f35bf03, 0x8217c8e4, 0x00000000, 0x153402d6],
+      [0xa072c108, 0x74020c96, 0xc60568fd, 0x95f9613e, 0x00000000, 0x3f4676c2],
+      [0xd845d5d8, 0xcdd235c4, 0x20426475, 0x6154e78b, 0x00000006, 0x202fb751],
+      [0xa4dbf71f, 0x9e90465e, 0xf08e022f, 0xa8be947f, 0x00000000, 0xbe43b5ce],
+      [0x3dbe627f, 0xa791f4b9, 0x28a5bd89, 0x1f5dfe93, 0x00000004, 0x02bf9ed4],
+      [0x5c1c53ee, 0xccf5102e, 0x198576e7, 0x07e3ae31, 0x00000008, 0x02ea8fb7],
+      [0xfef1e581, 0x04714067, 0xca6540c1, 0x059e73ec, 0x00000000, 0x31658095],
+      [0x1e2dd90c, 0x13dd6667, 0x8b2184c3, 0x248d1a42, 0x00000000, 0x4ca6d0c6],
+      // --- divisors in (0, 2^16-1) to test larger quotient high-words
+      // low(a)   high(a)    b          low(quot)  high(quot) rem
+      [0x86722b47, 0x2cd57c9a, 0x00003123, 0x2ae41b7a, 0x0000e995, 0x00000f99],
+      [0x1dd7884c, 0xf5e839bc, 0x00009eeb, 0x5c886242, 0x00018c21, 0x000099b6],
+      [0x5c53d625, 0x899fc7e5, 0x000087d7, 0xd625007a, 0x0001035c, 0x000019af],
+      [0x6932d932, 0x9d0a5488, 0x000051fb, 0x9d976143, 0x0001ea63, 0x00004981],
+      [0x4d18bb85, 0x0c92fb31, 0x00001d9f, 0x03265ab4, 0x00006cac, 0x000001b9],
+      [0xbe756768, 0xdea67ccb, 0x00008a03, 0x58add442, 0x00019cff, 0x000056a2],
+      [0xe2466f9a, 0x2521f114, 0x0000c350, 0xa0c0860d, 0x000030ab, 0x0000a48a],
+      [0xf00ddad1, 0xe2f5446a, 0x00002cfc, 0x762697a6, 0x00050b96, 0x00000b69],
+      [0xa879152a, 0x0a70e0a5, 0x00007cdf, 0xb44151b3, 0x00001567, 0x0000363d],
+      [0x7179a74c, 0x46083fff, 0x0000253c, 0x4d39ba6e, 0x0001e17f, 0x00000f84]
+    ];
+
+    for (var i = 0; i < testData.length; i++) {
+      var a = new jspb.arith.UInt64(testData[i][0], testData[i][1]);
+      var result = a.div(testData[i][2]);
+      var quotient = result[0];
+      var remainder = result[1];
+      assertEquals(quotient.lo, testData[i][3]);
+      assertEquals(quotient.hi, testData[i][4]);
+      assertEquals(remainder.lo, testData[i][5]);
+    }
+  });
+
+
+  /**
+   * Tests .toString() and .fromString().
+   */
+  it('testStrings', function() {
+    var testData = [
+        [0x5e84c935, 0xcae33d0e, '14619595947299359029'],
+        [0x62b3b8b8, 0x93480544, '10612738313170434232'],
+        [0x319bfb13, 0xc01c4172, '13843011313344445203'],
+        [0x5b8a65fb, 0xa5885b31, '11927883880638080507'],
+        [0x6bdb80f1, 0xb0d1b16b, '12741159895737008369'],
+        [0x4b82b442, 0x2e0d8c97, '3318463081876730946'],
+        [0x780d5208, 0x7d76752c, '9040542135845999112'],
+        [0x2e46800f, 0x0993778d, '690026616168284175'],
+        [0xf00a7e32, 0xcd8e3931, '14811839111111540274'],
+        [0x1baeccd6, 0x923048c4, '10533999535534820566'],
+        [0x03669d29, 0xbff3ab72, '13831587386756603177'],
+        [0x2526073e, 0x01affc81, '121593346566522686'],
+        [0xc24244e0, 0xd7f40d0e, '15561076969511732448'],
+        [0xc56a341e, 0xa68b66a7, '12000798502816461854'],
+        [0x8738d64d, 0xbfe78604, '13828168534871037517'],
+        [0x5baff03b, 0xd7572aea, '15516918227177304123'],
+        [0x4a843d8a, 0x864e132b, '9677693725920476554'],
+        [0x25b4e94d, 0x22b54dc6, '2500990681505655117'],
+        [0x6bbe664b, 0x55a5cc0e, '6171563226690381387'],
+        [0xee916c81, 0xb00aabb3, '12685140089732426881']
+    ];
+
+    for (var i = 0; i < testData.length; i++) {
+      var a = new jspb.arith.UInt64(testData[i][0], testData[i][1]);
+      var roundtrip = jspb.arith.UInt64.fromString(a.toString());
+      assertEquals(roundtrip.lo, a.lo);
+      assertEquals(roundtrip.hi, a.hi);
+      assertEquals(a.toString(), testData[i][2]);
+    }
+  });
+
+
+  /**
+   * Tests signed Int64s. These are built on UInt64s, so we only need to test
+   * the explicit overrides: .toString() and .fromString().
+   */
+  it('testSignedInt64', function() {
+    var testStrings = [
+        '-7847499644178593666',
+        '3771946501229139523',
+        '2872856549054995060',
+        '-5780049594274350904',
+        '3383785956695105201',
+        '2973055184857072610',
+        '-3879428459215627206',
+        '4589812431064156631',
+        '8484075557333689940',
+        '1075325817098092407',
+        '-4346697501012292314',
+        '2488620459718316637',
+        '6112655187423520672',
+        '-3655278273928612104',
+        '3439154019435803196',
+        '1004112478843763757',
+        '-6587790776614368413',
+        '664320065099714586',
+        '4760412909973292912',
+        '-7911903989602274672'
+    ];
+
+    for (var i = 0; i < testStrings.length; i++) {
+      var roundtrip =
+          jspb.arith.Int64.fromString(testStrings[i]).toString();
+      assertEquals(roundtrip, testStrings[i]);
+    }
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/binary/decoder_test.js b/js/compatibility_tests/v3.1.0/binary/decoder_test.js
new file mode 100644
index 00000000..ac312648
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/binary/decoder_test.js
@@ -0,0 +1,334 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/**
+ * @fileoverview Test cases for jspb's binary protocol buffer decoder.
+ *
+ * There are two particular magic numbers that need to be pointed out -
+ * 2^64-1025 is the largest number representable as both a double and an
+ * unsigned 64-bit integer, and 2^63-513 is the largest number representable as
+ * both a double and a signed 64-bit integer.
+ *
+ * Test suite is written using Jasmine -- see http://jasmine.github.io/
+ *
+ * @author aappleby@google.com (Austin Appleby)
+ */
+
+goog.require('goog.testing.asserts');
+goog.require('jspb.BinaryConstants');
+goog.require('jspb.BinaryDecoder');
+goog.require('jspb.BinaryEncoder');
+
+
+/**
+ * Tests encoding and decoding of unsigned types.
+ * @param {Function} readValue
+ * @param {Function} writeValue
+ * @param {number} epsilon
+ * @param {number} upperLimit
+ * @param {Function} filter
+ * @suppress {missingProperties|visibility}
+ */
+function doTestUnsignedValue(readValue,
+    writeValue, epsilon, upperLimit, filter) {
+  var encoder = new jspb.BinaryEncoder();
+
+  // Encode zero and limits.
+  writeValue.call(encoder, filter(0));
+  writeValue.call(encoder, filter(epsilon));
+  writeValue.call(encoder, filter(upperLimit));
+
+  // Encode positive values.
+  for (var cursor = epsilon; cursor < upperLimit; cursor *= 1.1) {
+    writeValue.call(encoder, filter(cursor));
+  }
+
+  var decoder = jspb.BinaryDecoder.alloc(encoder.end());
+
+  // Check zero and limits.
+  assertEquals(filter(0), readValue.call(decoder));
+  assertEquals(filter(epsilon), readValue.call(decoder));
+  assertEquals(filter(upperLimit), readValue.call(decoder));
+
+  // Check positive values.
+  for (var cursor = epsilon; cursor < upperLimit; cursor *= 1.1) {
+    if (filter(cursor) != readValue.call(decoder)) throw 'fail!';
+  }
+
+  // Encoding values outside the valid range should assert.
+  assertThrows(function() {writeValue.call(encoder, -1);});
+  assertThrows(function() {writeValue.call(encoder, upperLimit * 1.1);});
+}
+
+
+/**
+ * Tests encoding and decoding of signed types.
+ * @param {Function} readValue
+ * @param {Function} writeValue
+ * @param {number} epsilon
+ * @param {number} lowerLimit
+ * @param {number} upperLimit
+ * @param {Function} filter
+ * @suppress {missingProperties}
+ */
+function doTestSignedValue(readValue,
+    writeValue, epsilon, lowerLimit, upperLimit, filter) {
+  var encoder = new jspb.BinaryEncoder();
+
+  // Encode zero and limits.
+  writeValue.call(encoder, filter(lowerLimit));
+  writeValue.call(encoder, filter(-epsilon));
+  writeValue.call(encoder, filter(0));
+  writeValue.call(encoder, filter(epsilon));
+  writeValue.call(encoder, filter(upperLimit));
+
+  var inputValues = [];
+
+  // Encode negative values.
+  for (var cursor = lowerLimit; cursor < -epsilon; cursor /= 1.1) {
+    var val = filter(cursor);
+    writeValue.call(encoder, val);
+    inputValues.push(val);
+  }
+
+  // Encode positive values.
+  for (var cursor = epsilon; cursor < upperLimit; cursor *= 1.1) {
+    var val = filter(cursor);
+    writeValue.call(encoder, val);
+    inputValues.push(val);
+  }
+
+  var decoder = jspb.BinaryDecoder.alloc(encoder.end());
+
+  // Check zero and limits.
+  assertEquals(filter(lowerLimit), readValue.call(decoder));
+  assertEquals(filter(-epsilon), readValue.call(decoder));
+  assertEquals(filter(0), readValue.call(decoder));
+  assertEquals(filter(epsilon), readValue.call(decoder));
+  assertEquals(filter(upperLimit), readValue.call(decoder));
+
+  // Verify decoded values.
+  for (var i = 0; i < inputValues.length; i++) {
+    assertEquals(inputValues[i], readValue.call(decoder));
+  }
+
+  // Encoding values outside the valid range should assert.
+  assertThrows(function() {writeValue.call(encoder, lowerLimit * 1.1);});
+  assertThrows(function() {writeValue.call(encoder, upperLimit * 1.1);});
+}
+
+describe('binaryDecoderTest', function() {
+  /**
+   * Tests the decoder instance cache.
+   */
+  it('testInstanceCache', /** @suppress {visibility} */ function() {
+    // Empty the instance caches.
+    jspb.BinaryDecoder.instanceCache_ = [];
+
+    // Allocating and then freeing a decoder should put it in the instance
+    // cache.
+    jspb.BinaryDecoder.alloc().free();
+
+    assertEquals(1, jspb.BinaryDecoder.instanceCache_.length);
+
+    // Allocating and then freeing three decoders should leave us with three in
+    // the cache.
+
+    var decoder1 = jspb.BinaryDecoder.alloc();
+    var decoder2 = jspb.BinaryDecoder.alloc();
+    var decoder3 = jspb.BinaryDecoder.alloc();
+    decoder1.free();
+    decoder2.free();
+    decoder3.free();
+
+    assertEquals(3, jspb.BinaryDecoder.instanceCache_.length);
+  });
+
+
+  /**
+   * Tests reading 64-bit integers as hash strings.
+   */
+  it('testHashStrings', function() {
+    var encoder = new jspb.BinaryEncoder();
+
+    var hashA = String.fromCharCode(0x00, 0x00, 0x00, 0x00,
+                                    0x00, 0x00, 0x00, 0x00);
+    var hashB = String.fromCharCode(0x12, 0x34, 0x00, 0x00,
+                                    0x00, 0x00, 0x00, 0x00);
+    var hashC = String.fromCharCode(0x12, 0x34, 0x56, 0x78,
+                                    0x87, 0x65, 0x43, 0x21);
+    var hashD = String.fromCharCode(0xFF, 0xFF, 0xFF, 0xFF,
+                                    0xFF, 0xFF, 0xFF, 0xFF);
+
+    encoder.writeVarintHash64(hashA);
+    encoder.writeVarintHash64(hashB);
+    encoder.writeVarintHash64(hashC);
+    encoder.writeVarintHash64(hashD);
+
+    encoder.writeFixedHash64(hashA);
+    encoder.writeFixedHash64(hashB);
+    encoder.writeFixedHash64(hashC);
+    encoder.writeFixedHash64(hashD);
+
+    var decoder = jspb.BinaryDecoder.alloc(encoder.end());
+
+    assertEquals(hashA, decoder.readVarintHash64());
+    assertEquals(hashB, decoder.readVarintHash64());
+    assertEquals(hashC, decoder.readVarintHash64());
+    assertEquals(hashD, decoder.readVarintHash64());
+
+    assertEquals(hashA, decoder.readFixedHash64());
+    assertEquals(hashB, decoder.readFixedHash64());
+    assertEquals(hashC, decoder.readFixedHash64());
+    assertEquals(hashD, decoder.readFixedHash64());
+  });
+
+
+  /**
+   * Verifies that misuse of the decoder class triggers assertions.
+   * @suppress {checkTypes|visibility}
+   */
+  it('testDecodeErrors', function() {
+    // Reading a value past the end of the stream should trigger an assertion.
+    var decoder = jspb.BinaryDecoder.alloc([0, 1, 2]);
+    assertThrows(function() {decoder.readUint64()});
+
+    // Overlong varints should trigger assertions.
+    decoder.setBlock([255, 255, 255, 255, 255, 255,
+                      255, 255, 255, 255, 255, 0]);
+    assertThrows(function() {decoder.readUnsignedVarint64()});
+    decoder.reset();
+    assertThrows(function() {decoder.readSignedVarint64()});
+    decoder.reset();
+    assertThrows(function() {decoder.readZigzagVarint64()});
+
+    // Positive 32-bit varints encoded with 1 bits in positions 33 through 35
+    // should trigger assertions.
+    decoder.setBlock([255, 255, 255, 255, 0x1F]);
+    assertThrows(function() {decoder.readUnsignedVarint32()});
+
+    decoder.setBlock([255, 255, 255, 255, 0x2F]);
+    assertThrows(function() {decoder.readUnsignedVarint32()});
+
+    decoder.setBlock([255, 255, 255, 255, 0x4F]);
+    assertThrows(function() {decoder.readUnsignedVarint32()});
+
+    // Negative 32-bit varints encoded with non-1 bits in the high dword should
+    // trigger assertions.
+    decoder.setBlock([255, 255, 255, 255, 255, 255, 0, 255, 255, 1]);
+    assertThrows(function() {decoder.readUnsignedVarint32()});
+
+    decoder.setBlock([255, 255, 255, 255, 255, 255, 255, 255, 255, 0]);
+    assertThrows(function() {decoder.readUnsignedVarint32()});
+  });
+
+
+  /**
+   * Tests encoding and decoding of unsigned integers.
+   */
+  it('testUnsignedIntegers', function() {
+    doTestUnsignedValue(
+        jspb.BinaryDecoder.prototype.readUint8,
+        jspb.BinaryEncoder.prototype.writeUint8,
+        1, 0xFF, Math.round);
+
+    doTestUnsignedValue(
+        jspb.BinaryDecoder.prototype.readUint16,
+        jspb.BinaryEncoder.prototype.writeUint16,
+        1, 0xFFFF, Math.round);
+
+    doTestUnsignedValue(
+        jspb.BinaryDecoder.prototype.readUint32,
+        jspb.BinaryEncoder.prototype.writeUint32,
+        1, 0xFFFFFFFF, Math.round);
+
+    doTestUnsignedValue(
+        jspb.BinaryDecoder.prototype.readUint64,
+        jspb.BinaryEncoder.prototype.writeUint64,
+        1, Math.pow(2, 64) - 1025, Math.round);
+  });
+
+
+  /**
+   * Tests encoding and decoding of signed integers.
+   */
+  it('testSignedIntegers', function() {
+    doTestSignedValue(
+        jspb.BinaryDecoder.prototype.readInt8,
+        jspb.BinaryEncoder.prototype.writeInt8,
+        1, -0x80, 0x7F, Math.round);
+
+    doTestSignedValue(
+        jspb.BinaryDecoder.prototype.readInt16,
+        jspb.BinaryEncoder.prototype.writeInt16,
+        1, -0x8000, 0x7FFF, Math.round);
+
+    doTestSignedValue(
+        jspb.BinaryDecoder.prototype.readInt32,
+        jspb.BinaryEncoder.prototype.writeInt32,
+        1, -0x80000000, 0x7FFFFFFF, Math.round);
+
+    doTestSignedValue(
+        jspb.BinaryDecoder.prototype.readInt64,
+        jspb.BinaryEncoder.prototype.writeInt64,
+        1, -Math.pow(2, 63), Math.pow(2, 63) - 513, Math.round);
+  });
+
+
+  /**
+   * Tests encoding and decoding of floats.
+   */
+  it('testFloats', function() {
+    /**
+     * @param {number} x
+     * @return {number}
+     */
+    function truncate(x) {
+      var temp = new Float32Array(1);
+      temp[0] = x;
+      return temp[0];
+    }
+    doTestSignedValue(
+        jspb.BinaryDecoder.prototype.readFloat,
+        jspb.BinaryEncoder.prototype.writeFloat,
+        jspb.BinaryConstants.FLOAT32_EPS,
+        -jspb.BinaryConstants.FLOAT32_MAX,
+        jspb.BinaryConstants.FLOAT32_MAX,
+        truncate);
+
+    doTestSignedValue(
+        jspb.BinaryDecoder.prototype.readDouble,
+        jspb.BinaryEncoder.prototype.writeDouble,
+        jspb.BinaryConstants.FLOAT64_EPS * 10,
+        -jspb.BinaryConstants.FLOAT64_MAX,
+        jspb.BinaryConstants.FLOAT64_MAX,
+        function(x) { return x; });
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/binary/proto_test.js b/js/compatibility_tests/v3.1.0/binary/proto_test.js
new file mode 100644
index 00000000..26e1d30f
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/binary/proto_test.js
@@ -0,0 +1,628 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Test suite is written using Jasmine -- see http://jasmine.github.io/
+
+goog.require('goog.crypt.base64');
+goog.require('goog.testing.asserts');
+goog.require('jspb.Message');
+
+// CommonJS-LoadFromFile: ../testbinary_pb proto.jspb.test
+goog.require('proto.jspb.test.ExtendsWithMessage');
+goog.require('proto.jspb.test.ForeignEnum');
+goog.require('proto.jspb.test.ForeignMessage');
+goog.require('proto.jspb.test.TestAllTypes');
+goog.require('proto.jspb.test.TestExtendable');
+goog.require('proto.jspb.test.extendOptionalBool');
+goog.require('proto.jspb.test.extendOptionalBytes');
+goog.require('proto.jspb.test.extendOptionalDouble');
+goog.require('proto.jspb.test.extendOptionalFixed32');
+goog.require('proto.jspb.test.extendOptionalFixed64');
+goog.require('proto.jspb.test.extendOptionalFloat');
+goog.require('proto.jspb.test.extendOptionalForeignEnum');
+goog.require('proto.jspb.test.extendOptionalInt32');
+goog.require('proto.jspb.test.extendOptionalInt64');
+goog.require('proto.jspb.test.extendOptionalSfixed32');
+goog.require('proto.jspb.test.extendOptionalSfixed64');
+goog.require('proto.jspb.test.extendOptionalSint32');
+goog.require('proto.jspb.test.extendOptionalSint64');
+goog.require('proto.jspb.test.extendOptionalString');
+goog.require('proto.jspb.test.extendOptionalUint32');
+goog.require('proto.jspb.test.extendOptionalUint64');
+goog.require('proto.jspb.test.extendPackedRepeatedBoolList');
+goog.require('proto.jspb.test.extendPackedRepeatedDoubleList');
+goog.require('proto.jspb.test.extendPackedRepeatedFixed32List');
+goog.require('proto.jspb.test.extendPackedRepeatedFixed64List');
+goog.require('proto.jspb.test.extendPackedRepeatedFloatList');
+goog.require('proto.jspb.test.extendPackedRepeatedForeignEnumList');
+goog.require('proto.jspb.test.extendPackedRepeatedInt32List');
+goog.require('proto.jspb.test.extendPackedRepeatedInt64List');
+goog.require('proto.jspb.test.extendPackedRepeatedSfixed32List');
+goog.require('proto.jspb.test.extendPackedRepeatedSfixed64List');
+goog.require('proto.jspb.test.extendPackedRepeatedSint32List');
+goog.require('proto.jspb.test.extendPackedRepeatedSint64List');
+goog.require('proto.jspb.test.extendPackedRepeatedUint32List');
+goog.require('proto.jspb.test.extendPackedRepeatedUint64List');
+goog.require('proto.jspb.test.extendRepeatedBoolList');
+goog.require('proto.jspb.test.extendRepeatedBytesList');
+goog.require('proto.jspb.test.extendRepeatedDoubleList');
+goog.require('proto.jspb.test.extendRepeatedFixed32List');
+goog.require('proto.jspb.test.extendRepeatedFixed64List');
+goog.require('proto.jspb.test.extendRepeatedFloatList');
+goog.require('proto.jspb.test.extendRepeatedForeignEnumList');
+goog.require('proto.jspb.test.extendRepeatedInt32List');
+goog.require('proto.jspb.test.extendRepeatedInt64List');
+goog.require('proto.jspb.test.extendRepeatedSfixed32List');
+goog.require('proto.jspb.test.extendRepeatedSfixed64List');
+goog.require('proto.jspb.test.extendRepeatedSint32List');
+goog.require('proto.jspb.test.extendRepeatedSint64List');
+goog.require('proto.jspb.test.extendRepeatedStringList');
+goog.require('proto.jspb.test.extendRepeatedUint32List');
+goog.require('proto.jspb.test.extendRepeatedUint64List');
+
+
+var suite = {};
+
+var BYTES = new Uint8Array([1, 2, 8, 9]);
+
+var BYTES_B64 = goog.crypt.base64.encodeByteArray(BYTES);
+
+
+/**
+ * Helper: fill all fields on a TestAllTypes message.
+ * @param {proto.jspb.test.TestAllTypes} msg
+ */
+function fillAllFields(msg) {
+  msg.setOptionalInt32(-42);
+  // can be exactly represented by JS number (64-bit double, i.e., 52-bit
+  // mantissa).
+  msg.setOptionalInt64(-0x7fffffff00000000);
+  msg.setOptionalUint32(0x80000000);
+  msg.setOptionalUint64(0xf000000000000000);
+  msg.setOptionalSint32(-100);
+  msg.setOptionalSint64(-0x8000000000000000);
+  msg.setOptionalFixed32(1234);
+  msg.setOptionalFixed64(0x1234567800000000);
+  msg.setOptionalSfixed32(-1234);
+  msg.setOptionalSfixed64(-0x1234567800000000);
+  msg.setOptionalFloat(1.5);
+  msg.setOptionalDouble(-1.5);
+  msg.setOptionalBool(true);
+  msg.setOptionalString('hello world');
+  msg.setOptionalBytes(BYTES);
+  msg.setOptionalGroup(new proto.jspb.test.TestAllTypes.OptionalGroup());
+  msg.getOptionalGroup().setA(100);
+  var submsg = new proto.jspb.test.ForeignMessage();
+  submsg.setC(16);
+  msg.setOptionalForeignMessage(submsg);
+  msg.setOptionalForeignEnum(proto.jspb.test.ForeignEnum.FOREIGN_FOO);
+  msg.setOneofString('oneof');
+
+
+  msg.setRepeatedInt32List([-42]);
+  msg.setRepeatedInt64List([-0x7fffffff00000000]);
+  msg.setRepeatedUint32List([0x80000000]);
+  msg.setRepeatedUint64List([0xf000000000000000]);
+  msg.setRepeatedSint32List([-100]);
+  msg.setRepeatedSint64List([-0x8000000000000000]);
+  msg.setRepeatedFixed32List([1234]);
+  msg.setRepeatedFixed64List([0x1234567800000000]);
+  msg.setRepeatedSfixed32List([-1234]);
+  msg.setRepeatedSfixed64List([-0x1234567800000000]);
+  msg.setRepeatedFloatList([1.5]);
+  msg.setRepeatedDoubleList([-1.5]);
+  msg.setRepeatedBoolList([true]);
+  msg.setRepeatedStringList(['hello world']);
+  msg.setRepeatedBytesList([BYTES, BYTES]);
+  msg.setRepeatedGroupList([new proto.jspb.test.TestAllTypes.RepeatedGroup()]);
+  msg.getRepeatedGroupList()[0].setA(100);
+  submsg = new proto.jspb.test.ForeignMessage();
+  submsg.setC(1000);
+  msg.setRepeatedForeignMessageList([submsg]);
+  msg.setRepeatedForeignEnumList([proto.jspb.test.ForeignEnum.FOREIGN_FOO]);
+
+  msg.setPackedRepeatedInt32List([-42]);
+  msg.setPackedRepeatedInt64List([-0x7fffffff00000000]);
+  msg.setPackedRepeatedUint32List([0x80000000]);
+  msg.setPackedRepeatedUint64List([0xf000000000000000]);
+  msg.setPackedRepeatedSint32List([-100]);
+  msg.setPackedRepeatedSint64List([-0x8000000000000000]);
+  msg.setPackedRepeatedFixed32List([1234]);
+  msg.setPackedRepeatedFixed64List([0x1234567800000000]);
+  msg.setPackedRepeatedSfixed32List([-1234]);
+  msg.setPackedRepeatedSfixed64List([-0x1234567800000000]);
+  msg.setPackedRepeatedFloatList([1.5]);
+  msg.setPackedRepeatedDoubleList([-1.5]);
+  msg.setPackedRepeatedBoolList([true]);
+
+}
+
+
+/**
+ * Helper: compare a bytes field to an expected value
+ * @param {Uint8Array|string} arr
+ * @param {Uint8Array} expected
+ * @return {boolean}
+ */
+function bytesCompare(arr, expected) {
+  if (goog.isString(arr)) {
+    arr = goog.crypt.base64.decodeStringToUint8Array(arr);
+  }
+  if (arr.length != expected.length) {
+    return false;
+  }
+  for (var i = 0; i < arr.length; i++) {
+    if (arr[i] != expected[i]) {
+      return false;
+    }
+  }
+  return true;
+}
+
+
+/**
+ * Helper: verify contents of given TestAllTypes message as set by
+ * fillAllFields().
+ * @param {proto.jspb.test.TestAllTypes} original
+ * @param {proto.jspb.test.TestAllTypes} copy
+ */
+function checkAllFields(original, copy) {
+  assertTrue(jspb.Message.equals(original, copy));
+
+  assertEquals(copy.getOptionalInt32(), -42);
+  assertEquals(copy.getOptionalInt64(), -0x7fffffff00000000);
+  assertEquals(copy.getOptionalUint32(), 0x80000000);
+  assertEquals(copy.getOptionalUint64(), 0xf000000000000000);
+  assertEquals(copy.getOptionalSint32(), -100);
+  assertEquals(copy.getOptionalSint64(), -0x8000000000000000);
+  assertEquals(copy.getOptionalFixed32(), 1234);
+  assertEquals(copy.getOptionalFixed64(), 0x1234567800000000);
+  assertEquals(copy.getOptionalSfixed32(), -1234);
+  assertEquals(copy.getOptionalSfixed64(), -0x1234567800000000);
+  assertEquals(copy.getOptionalFloat(), 1.5);
+  assertEquals(copy.getOptionalDouble(), -1.5);
+  assertEquals(copy.getOptionalBool(), true);
+  assertEquals(copy.getOptionalString(), 'hello world');
+  assertEquals(true, bytesCompare(copy.getOptionalBytes(), BYTES));
+  assertEquals(true, bytesCompare(copy.getOptionalBytes_asU8(), BYTES));
+  assertEquals(
+      copy.getOptionalBytes_asB64(), goog.crypt.base64.encodeByteArray(BYTES));
+
+  assertEquals(copy.getOptionalGroup().getA(), 100);
+  assertEquals(copy.getOptionalForeignMessage().getC(), 16);
+  assertEquals(copy.getOptionalForeignEnum(),
+      proto.jspb.test.ForeignEnum.FOREIGN_FOO);
+
+
+  assertEquals(copy.getOneofString(), 'oneof');
+  assertEquals(copy.getOneofFieldCase(),
+      proto.jspb.test.TestAllTypes.OneofFieldCase.ONEOF_STRING);
+
+  assertElementsEquals(copy.getRepeatedInt32List(), [-42]);
+  assertElementsEquals(copy.getRepeatedInt64List(), [-0x7fffffff00000000]);
+  assertElementsEquals(copy.getRepeatedUint32List(), [0x80000000]);
+  assertElementsEquals(copy.getRepeatedUint64List(), [0xf000000000000000]);
+  assertElementsEquals(copy.getRepeatedSint32List(), [-100]);
+  assertElementsEquals(copy.getRepeatedSint64List(), [-0x8000000000000000]);
+  assertElementsEquals(copy.getRepeatedFixed32List(), [1234]);
+  assertElementsEquals(copy.getRepeatedFixed64List(), [0x1234567800000000]);
+  assertElementsEquals(copy.getRepeatedSfixed32List(), [-1234]);
+  assertElementsEquals(copy.getRepeatedSfixed64List(), [-0x1234567800000000]);
+  assertElementsEquals(copy.getRepeatedFloatList(), [1.5]);
+  assertElementsEquals(copy.getRepeatedDoubleList(), [-1.5]);
+  assertElementsEquals(copy.getRepeatedBoolList(), [true]);
+  assertElementsEquals(copy.getRepeatedStringList(), ['hello world']);
+  assertEquals(copy.getRepeatedBytesList().length, 2);
+  assertEquals(true, bytesCompare(copy.getRepeatedBytesList_asU8()[0], BYTES));
+  assertEquals(true, bytesCompare(copy.getRepeatedBytesList()[0], BYTES));
+  assertEquals(true, bytesCompare(copy.getRepeatedBytesList_asU8()[1], BYTES));
+  assertEquals(copy.getRepeatedBytesList_asB64()[0], BYTES_B64);
+  assertEquals(copy.getRepeatedBytesList_asB64()[1], BYTES_B64);
+  assertEquals(copy.getRepeatedGroupList().length, 1);
+  assertEquals(copy.getRepeatedGroupList()[0].getA(), 100);
+  assertEquals(copy.getRepeatedForeignMessageList().length, 1);
+  assertEquals(copy.getRepeatedForeignMessageList()[0].getC(), 1000);
+  assertElementsEquals(copy.getRepeatedForeignEnumList(),
+      [proto.jspb.test.ForeignEnum.FOREIGN_FOO]);
+
+  assertElementsEquals(copy.getPackedRepeatedInt32List(), [-42]);
+  assertElementsEquals(copy.getPackedRepeatedInt64List(),
+      [-0x7fffffff00000000]);
+  assertElementsEquals(copy.getPackedRepeatedUint32List(), [0x80000000]);
+  assertElementsEquals(copy.getPackedRepeatedUint64List(),
+      [0xf000000000000000]);
+  assertElementsEquals(copy.getPackedRepeatedSint32List(), [-100]);
+  assertElementsEquals(copy.getPackedRepeatedSint64List(),
+      [-0x8000000000000000]);
+  assertElementsEquals(copy.getPackedRepeatedFixed32List(), [1234]);
+  assertElementsEquals(copy.getPackedRepeatedFixed64List(),
+      [0x1234567800000000]);
+  assertElementsEquals(copy.getPackedRepeatedSfixed32List(), [-1234]);
+  assertElementsEquals(copy.getPackedRepeatedSfixed64List(),
+      [-0x1234567800000000]);
+  assertElementsEquals(copy.getPackedRepeatedFloatList(), [1.5]);
+  assertElementsEquals(copy.getPackedRepeatedDoubleList(), [-1.5]);
+
+}
+
+
+/**
+ * Helper: verify that all expected extensions are present.
+ * @param {!proto.jspb.test.TestExtendable} msg
+ */
+function checkExtensions(msg) {
+  assertEquals(-42,
+      msg.getExtension(proto.jspb.test.extendOptionalInt32));
+  assertEquals(-0x7fffffff00000000,
+      msg.getExtension(proto.jspb.test.extendOptionalInt64));
+  assertEquals(0x80000000,
+      msg.getExtension(proto.jspb.test.extendOptionalUint32));
+  assertEquals(0xf000000000000000,
+      msg.getExtension(proto.jspb.test.extendOptionalUint64));
+  assertEquals(-100,
+      msg.getExtension(proto.jspb.test.extendOptionalSint32));
+  assertEquals(-0x8000000000000000,
+      msg.getExtension(proto.jspb.test.extendOptionalSint64));
+  assertEquals(1234,
+      msg.getExtension(proto.jspb.test.extendOptionalFixed32));
+  assertEquals(0x1234567800000000,
+      msg.getExtension(proto.jspb.test.extendOptionalFixed64));
+  assertEquals(-1234,
+      msg.getExtension(proto.jspb.test.extendOptionalSfixed32));
+  assertEquals(-0x1234567800000000,
+      msg.getExtension(proto.jspb.test.extendOptionalSfixed64));
+  assertEquals(1.5,
+      msg.getExtension(proto.jspb.test.extendOptionalFloat));
+  assertEquals(-1.5,
+      msg.getExtension(proto.jspb.test.extendOptionalDouble));
+  assertEquals(true,
+      msg.getExtension(proto.jspb.test.extendOptionalBool));
+  assertEquals('hello world',
+      msg.getExtension(proto.jspb.test.extendOptionalString));
+  assertEquals(
+      true, bytesCompare(
+                msg.getExtension(proto.jspb.test.extendOptionalBytes), BYTES));
+  assertEquals(16,
+      msg.getExtension(
+          proto.jspb.test.ExtendsWithMessage.optionalExtension).getFoo());
+
+
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedInt32List),
+      [-42]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedInt64List),
+      [-0x7fffffff00000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedUint32List),
+      [0x80000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedUint64List),
+      [0xf000000000000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedSint32List),
+      [-100]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedSint64List),
+      [-0x8000000000000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedFixed32List),
+      [1234]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedFixed64List),
+      [0x1234567800000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedSfixed32List),
+      [-1234]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedSfixed64List),
+      [-0x1234567800000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedFloatList),
+      [1.5]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedDoubleList),
+      [-1.5]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedBoolList),
+      [true]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedStringList),
+      ['hello world']);
+  assertEquals(
+      true,
+      bytesCompare(
+          msg.getExtension(proto.jspb.test.extendRepeatedBytesList)[0], BYTES));
+  assertEquals(1000,
+      msg.getExtension(
+          proto.jspb.test.ExtendsWithMessage.repeatedExtensionList)[0]
+      .getFoo());
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendRepeatedForeignEnumList),
+      [proto.jspb.test.ForeignEnum.FOREIGN_FOO]);
+
+
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedInt32List),
+      [-42]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedInt64List),
+      [-0x7fffffff00000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedUint32List),
+      [0x80000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedUint64List),
+      [0xf000000000000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedSint32List),
+      [-100]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedSint64List),
+      [-0x8000000000000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedFixed32List),
+      [1234]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedFixed64List),
+      [0x1234567800000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedSfixed32List),
+      [-1234]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedSfixed64List),
+      [-0x1234567800000000]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedFloatList),
+      [1.5]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedDoubleList),
+      [-1.5]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedBoolList),
+      [true]);
+  assertElementsEquals(
+      msg.getExtension(proto.jspb.test.extendPackedRepeatedForeignEnumList),
+      [proto.jspb.test.ForeignEnum.FOREIGN_FOO]);
+
+}
+
+
+describe('protoBinaryTest', function() {
+  /**
+   * Tests a basic serialization-deserializaton round-trip with all supported
+   * field types (on the TestAllTypes message type).
+   */
+  it('testRoundTrip', function() {
+    var msg = new proto.jspb.test.TestAllTypes();
+    fillAllFields(msg);
+    var encoded = msg.serializeBinary();
+    var decoded = proto.jspb.test.TestAllTypes.deserializeBinary(encoded);
+    checkAllFields(msg, decoded);
+  });
+
+  /**
+   * Test that base64 string and Uint8Array are interchangeable in bytes fields.
+   */
+  it('testBytesFieldsGettersInterop', function() {
+    var msg = new proto.jspb.test.TestAllTypes();
+    // Set from a base64 string and check all the getters work.
+    msg.setOptionalBytes(BYTES_B64);
+    assertTrue(bytesCompare(msg.getOptionalBytes_asU8(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes_asB64(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+    // Test binary serialize round trip doesn't break it.
+    msg = proto.jspb.test.TestAllTypes.deserializeBinary(msg.serializeBinary());
+    assertTrue(bytesCompare(msg.getOptionalBytes_asU8(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes_asB64(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+    msg = new proto.jspb.test.TestAllTypes();
+    // Set from a Uint8Array and check all the getters work.
+    msg.setOptionalBytes(BYTES);
+    assertTrue(bytesCompare(msg.getOptionalBytes_asU8(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes_asB64(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+  });
+
+  /**
+   * Test that bytes setters will receive result of any of the getters.
+   */
+  it('testBytesFieldsSettersInterop', function() {
+    var msg = new proto.jspb.test.TestAllTypes();
+    msg.setOptionalBytes(BYTES);
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+    msg.setOptionalBytes(msg.getOptionalBytes());
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+    msg.setOptionalBytes(msg.getOptionalBytes_asB64());
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+    msg.setOptionalBytes(msg.getOptionalBytes_asU8());
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+  });
+
+  /**
+   * Test that bytes setters will receive result of any of the getters.
+   */
+  it('testRepeatedBytesGetters', function() {
+    var msg = new proto.jspb.test.TestAllTypes();
+
+    function assertGetters() {
+      assertTrue(goog.isString(msg.getRepeatedBytesList_asB64()[0]));
+      assertTrue(goog.isString(msg.getRepeatedBytesList_asB64()[1]));
+      assertTrue(msg.getRepeatedBytesList_asU8()[0] instanceof Uint8Array);
+      assertTrue(msg.getRepeatedBytesList_asU8()[1] instanceof Uint8Array);
+
+      assertTrue(bytesCompare(msg.getRepeatedBytesList()[0], BYTES));
+      assertTrue(bytesCompare(msg.getRepeatedBytesList()[1], BYTES));
+      assertTrue(bytesCompare(msg.getRepeatedBytesList_asB64()[0], BYTES));
+      assertTrue(bytesCompare(msg.getRepeatedBytesList_asB64()[1], BYTES));
+      assertTrue(bytesCompare(msg.getRepeatedBytesList_asU8()[0], BYTES));
+      assertTrue(bytesCompare(msg.getRepeatedBytesList_asU8()[1], BYTES));
+    }
+
+    msg.setRepeatedBytesList([BYTES, BYTES]);
+    assertGetters();
+
+    msg.setRepeatedBytesList([BYTES_B64, BYTES_B64]);
+    assertGetters();
+
+    msg.setRepeatedBytesList([]);
+    assertEquals(0, msg.getRepeatedBytesList().length);
+    assertEquals(0, msg.getRepeatedBytesList_asB64().length);
+    assertEquals(0, msg.getRepeatedBytesList_asU8().length);
+  });
+
+  /**
+   * Helper: fill all extension values.
+   * @param {proto.jspb.test.TestExtendable} msg
+   */
+  function fillExtensions(msg) {
+    msg.setExtension(
+        proto.jspb.test.extendOptionalInt32, -42);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalInt64, -0x7fffffff00000000);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalUint32, 0x80000000);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalUint64, 0xf000000000000000);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalSint32, -100);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalSint64, -0x8000000000000000);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalFixed32, 1234);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalFixed64, 0x1234567800000000);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalSfixed32, -1234);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalSfixed64, -0x1234567800000000);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalFloat, 1.5);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalDouble, -1.5);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalBool, true);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalString, 'hello world');
+    msg.setExtension(proto.jspb.test.extendOptionalBytes, BYTES);
+    var submsg = new proto.jspb.test.ExtendsWithMessage();
+    submsg.setFoo(16);
+    msg.setExtension(
+        proto.jspb.test.ExtendsWithMessage.optionalExtension, submsg);
+    msg.setExtension(
+        proto.jspb.test.extendOptionalForeignEnum,
+        proto.jspb.test.ForeignEnum.FOREIGN_FOO);
+
+
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedInt32List, [-42]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedInt64List, [-0x7fffffff00000000]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedUint32List, [0x80000000]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedUint64List, [0xf000000000000000]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedSint32List, [-100]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedSint64List, [-0x8000000000000000]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedFixed32List, [1234]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedFixed64List, [0x1234567800000000]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedSfixed32List, [-1234]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedSfixed64List, [-0x1234567800000000]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedFloatList, [1.5]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedDoubleList, [-1.5]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedBoolList, [true]);
+    msg.setExtension(
+        proto.jspb.test.extendRepeatedStringList, ['hello world']);
+    msg.setExtension(proto.jspb.test.extendRepeatedBytesList, [BYTES]);
+    submsg = new proto.jspb.test.ExtendsWithMessage();
+    submsg.setFoo(1000);
+    msg.setExtension(
+        proto.jspb.test.ExtendsWithMessage.repeatedExtensionList, [submsg]);
+    msg.setExtension(proto.jspb.test.extendRepeatedForeignEnumList,
+        [proto.jspb.test.ForeignEnum.FOREIGN_FOO]);
+
+
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedInt32List, [-42]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedInt64List, [-0x7fffffff00000000]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedUint32List, [0x80000000]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedUint64List, [0xf000000000000000]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedSint32List, [-100]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedSint64List, [-0x8000000000000000]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedFixed32List, [1234]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedFixed64List, [0x1234567800000000]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedSfixed32List, [-1234]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedSfixed64List,
+        [-0x1234567800000000]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedFloatList, [1.5]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedDoubleList, [-1.5]);
+    msg.setExtension(
+        proto.jspb.test.extendPackedRepeatedBoolList, [true]);
+    msg.setExtension(proto.jspb.test.extendPackedRepeatedForeignEnumList,
+        [proto.jspb.test.ForeignEnum.FOREIGN_FOO]);
+
+  }
+
+
+  /**
+   * Tests extension serialization and deserialization.
+   */
+  it('testExtensions', function() {
+    var msg = new proto.jspb.test.TestExtendable();
+    fillExtensions(msg);
+    var encoded = msg.serializeBinary();
+    var decoded = proto.jspb.test.TestExtendable.deserializeBinary(encoded);
+    checkExtensions(decoded);
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/binary/reader_test.js b/js/compatibility_tests/v3.1.0/binary/reader_test.js
new file mode 100644
index 00000000..95711385
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/binary/reader_test.js
@@ -0,0 +1,922 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/**
+ * @fileoverview Test cases for jspb's binary protocol buffer reader.
+ *
+ * There are two particular magic numbers that need to be pointed out -
+ * 2^64-1025 is the largest number representable as both a double and an
+ * unsigned 64-bit integer, and 2^63-513 is the largest number representable as
+ * both a double and a signed 64-bit integer.
+ *
+ * Test suite is written using Jasmine -- see http://jasmine.github.io/
+ *
+ * @author aappleby@google.com (Austin Appleby)
+ */
+
+goog.require('goog.testing.asserts');
+goog.require('jspb.BinaryConstants');
+goog.require('jspb.BinaryDecoder');
+goog.require('jspb.BinaryReader');
+goog.require('jspb.BinaryWriter');
+
+
+
+describe('binaryReaderTest', function() {
+  /**
+   * Tests the reader instance cache.
+   */
+  it('testInstanceCaches', /** @suppress {visibility} */ function() {
+    var writer = new jspb.BinaryWriter();
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+    writer.writeMessage(1, dummyMessage, goog.nullFunction);
+    writer.writeMessage(2, dummyMessage, goog.nullFunction);
+
+    var buffer = writer.getResultBuffer();
+
+    // Empty the instance caches.
+    jspb.BinaryReader.instanceCache_ = [];
+
+    // Allocating and then freeing three decoders should leave us with three in
+    // the cache.
+
+    var decoder1 = jspb.BinaryDecoder.alloc();
+    var decoder2 = jspb.BinaryDecoder.alloc();
+    var decoder3 = jspb.BinaryDecoder.alloc();
+    decoder1.free();
+    decoder2.free();
+    decoder3.free();
+
+    assertEquals(3, jspb.BinaryDecoder.instanceCache_.length);
+    assertEquals(0, jspb.BinaryReader.instanceCache_.length);
+
+    // Allocating and then freeing a reader should remove one decoder from its
+    // cache, but it should stay stuck to the reader afterwards since we can't
+    // have a reader without a decoder.
+    jspb.BinaryReader.alloc().free();
+
+    assertEquals(2, jspb.BinaryDecoder.instanceCache_.length);
+    assertEquals(1, jspb.BinaryReader.instanceCache_.length);
+
+    // Allocating a reader should remove a reader from the cache.
+    var reader = jspb.BinaryReader.alloc(buffer);
+
+    assertEquals(2, jspb.BinaryDecoder.instanceCache_.length);
+    assertEquals(0, jspb.BinaryReader.instanceCache_.length);
+
+    // Processing the message reuses the current reader.
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    reader.readMessage(dummyMessage, function() {
+      assertEquals(0, jspb.BinaryReader.instanceCache_.length);
+    });
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    reader.readMessage(dummyMessage, function() {
+      assertEquals(0, jspb.BinaryReader.instanceCache_.length);
+    });
+
+    assertEquals(false, reader.nextField());
+
+    assertEquals(2, jspb.BinaryDecoder.instanceCache_.length);
+    assertEquals(0, jspb.BinaryReader.instanceCache_.length);
+
+    // Freeing the reader should put it back into the cache.
+    reader.free();
+
+    assertEquals(2, jspb.BinaryDecoder.instanceCache_.length);
+    assertEquals(1, jspb.BinaryReader.instanceCache_.length);
+  });
+
+
+  /**
+   * @param {number} x
+   * @return {number}
+   */
+  function truncate(x) {
+    var temp = new Float32Array(1);
+    temp[0] = x;
+    return temp[0];
+  }
+
+
+  /**
+   * Verifies that misuse of the reader class triggers assertions.
+   */
+  it('testReadErrors', /** @suppress {checkTypes|visibility} */ function() {
+    // Calling readMessage on a non-delimited field should trigger an
+    // assertion.
+    var reader = jspb.BinaryReader.alloc([8, 1]);
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+    reader.nextField();
+    assertThrows(function() {
+      reader.readMessage(dummyMessage, goog.nullFunction);
+    });
+
+    // Reading past the end of the stream should trigger an assertion.
+    reader = jspb.BinaryReader.alloc([9, 1]);
+    reader.nextField();
+    assertThrows(function() {reader.readFixed64()});
+
+    // Reading past the end of a submessage should trigger an assertion.
+    reader = jspb.BinaryReader.alloc([10, 4, 13, 1, 1, 1]);
+    reader.nextField();
+    reader.readMessage(dummyMessage, function() {
+      reader.nextField();
+      assertThrows(function() {reader.readFixed32()});
+    });
+
+    // Skipping an invalid field should trigger an assertion.
+    reader = jspb.BinaryReader.alloc([12, 1]);
+    reader.nextWireType_ = 1000;
+    assertThrows(function() {reader.skipField()});
+
+    // Reading fields with the wrong wire type should assert.
+    reader = jspb.BinaryReader.alloc([9, 0, 0, 0, 0, 0, 0, 0, 0]);
+    reader.nextField();
+    assertThrows(function() {reader.readInt32()});
+    assertThrows(function() {reader.readInt32String()});
+    assertThrows(function() {reader.readInt64()});
+    assertThrows(function() {reader.readInt64String()});
+    assertThrows(function() {reader.readUint32()});
+    assertThrows(function() {reader.readUint32String()});
+    assertThrows(function() {reader.readUint64()});
+    assertThrows(function() {reader.readUint64String()});
+    assertThrows(function() {reader.readSint32()});
+    assertThrows(function() {reader.readBool()});
+    assertThrows(function() {reader.readEnum()});
+
+    reader = jspb.BinaryReader.alloc([8, 1]);
+    reader.nextField();
+    assertThrows(function() {reader.readFixed32()});
+    assertThrows(function() {reader.readFixed64()});
+    assertThrows(function() {reader.readSfixed32()});
+    assertThrows(function() {reader.readSfixed64()});
+    assertThrows(function() {reader.readFloat()});
+    assertThrows(function() {reader.readDouble()});
+
+    assertThrows(function() {reader.readString()});
+    assertThrows(function() {reader.readBytes()});
+  });
+
+
+  /**
+   * Tests encoding and decoding of unsigned field types.
+   * @param {Function} readField
+   * @param {Function} writeField
+   * @param {number} epsilon
+   * @param {number} upperLimit
+   * @param {Function} filter
+   * @private
+   * @suppress {missingProperties}
+   */
+  var doTestUnsignedField_ = function(readField,
+      writeField, epsilon, upperLimit, filter) {
+    assertNotNull(readField);
+    assertNotNull(writeField);
+
+    var writer = new jspb.BinaryWriter();
+
+    // Encode zero and limits.
+    writeField.call(writer, 1, filter(0));
+    writeField.call(writer, 2, filter(epsilon));
+    writeField.call(writer, 3, filter(upperLimit));
+
+    // Encode positive values.
+    for (var cursor = epsilon; cursor < upperLimit; cursor *= 1.1) {
+      writeField.call(writer, 4, filter(cursor));
+    }
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    // Check zero and limits.
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    assertEquals(filter(0), readField.call(reader));
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    assertEquals(filter(epsilon), readField.call(reader));
+
+    reader.nextField();
+    assertEquals(3, reader.getFieldNumber());
+    assertEquals(filter(upperLimit), readField.call(reader));
+
+    // Check positive values.
+    for (var cursor = epsilon; cursor < upperLimit; cursor *= 1.1) {
+      reader.nextField();
+      if (4 != reader.getFieldNumber()) throw 'fail!';
+      if (filter(cursor) != readField.call(reader)) throw 'fail!';
+    }
+  };
+
+
+  /**
+   * Tests encoding and decoding of signed field types.
+   * @param {Function} readField
+   * @param {Function} writeField
+   * @param {number} epsilon
+   * @param {number} lowerLimit
+   * @param {number} upperLimit
+   * @param {Function} filter
+   * @private
+   * @suppress {missingProperties}
+   */
+  var doTestSignedField_ = function(readField,
+      writeField, epsilon, lowerLimit, upperLimit, filter) {
+    var writer = new jspb.BinaryWriter();
+
+    // Encode zero and limits.
+    writeField.call(writer, 1, filter(lowerLimit));
+    writeField.call(writer, 2, filter(-epsilon));
+    writeField.call(writer, 3, filter(0));
+    writeField.call(writer, 4, filter(epsilon));
+    writeField.call(writer, 5, filter(upperLimit));
+
+    var inputValues = [];
+
+    // Encode negative values.
+    for (var cursor = lowerLimit; cursor < -epsilon; cursor /= 1.1) {
+      var val = filter(cursor);
+      writeField.call(writer, 6, val);
+      inputValues.push({
+        fieldNumber: 6,
+        value: val
+      });
+    }
+
+    // Encode positive values.
+    for (var cursor = epsilon; cursor < upperLimit; cursor *= 1.1) {
+      var val = filter(cursor);
+      writeField.call(writer, 7, val);
+      inputValues.push({
+        fieldNumber: 7,
+        value: val
+      });
+    }
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    // Check zero and limits.
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    assertEquals(filter(lowerLimit), readField.call(reader));
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    assertEquals(filter(-epsilon), readField.call(reader));
+
+    reader.nextField();
+    assertEquals(3, reader.getFieldNumber());
+    assertEquals(filter(0), readField.call(reader));
+
+    reader.nextField();
+    assertEquals(4, reader.getFieldNumber());
+    assertEquals(filter(epsilon), readField.call(reader));
+
+    reader.nextField();
+    assertEquals(5, reader.getFieldNumber());
+    assertEquals(filter(upperLimit), readField.call(reader));
+
+    for (var i = 0; i < inputValues.length; i++) {
+      var expected = inputValues[i];
+      reader.nextField();
+      assertEquals(expected.fieldNumber, reader.getFieldNumber());
+      assertEquals(expected.value, readField.call(reader));
+    }
+  };
+
+
+  /**
+   * Tests fields that use varint encoding.
+   */
+  it('testVarintFields', function() {
+    assertNotUndefined(jspb.BinaryReader.prototype.readUint32);
+    assertNotUndefined(jspb.BinaryWriter.prototype.writeUint32);
+    assertNotUndefined(jspb.BinaryReader.prototype.readUint64);
+    assertNotUndefined(jspb.BinaryWriter.prototype.writeUint64);
+    assertNotUndefined(jspb.BinaryReader.prototype.readBool);
+    assertNotUndefined(jspb.BinaryWriter.prototype.writeBool);
+    doTestUnsignedField_(
+        jspb.BinaryReader.prototype.readUint32,
+        jspb.BinaryWriter.prototype.writeUint32,
+        1, Math.pow(2, 32) - 1, Math.round);
+
+    doTestUnsignedField_(
+        jspb.BinaryReader.prototype.readUint64,
+        jspb.BinaryWriter.prototype.writeUint64,
+        1, Math.pow(2, 64) - 1025, Math.round);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readInt32,
+        jspb.BinaryWriter.prototype.writeInt32,
+        1, -Math.pow(2, 31), Math.pow(2, 31) - 1, Math.round);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readInt64,
+        jspb.BinaryWriter.prototype.writeInt64,
+        1, -Math.pow(2, 63), Math.pow(2, 63) - 513, Math.round);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readEnum,
+        jspb.BinaryWriter.prototype.writeEnum,
+        1, -Math.pow(2, 31), Math.pow(2, 31) - 1, Math.round);
+
+    doTestUnsignedField_(
+        jspb.BinaryReader.prototype.readBool,
+        jspb.BinaryWriter.prototype.writeBool,
+        1, 1, function(x) { return !!x; });
+  });
+
+
+  /**
+   * Tests reading a field from hexadecimal string (format: '08 BE EF').
+   * @param {Function} readField
+   * @param {number} expected
+   * @param {string} hexString
+   */
+  function doTestHexStringVarint_(readField, expected, hexString) {
+    var bytesCount = (hexString.length + 1) / 3;
+    var bytes = new Uint8Array(bytesCount);
+    for (var i = 0; i < bytesCount; i++) {
+      bytes[i] = parseInt(hexString.substring(i * 3, i * 3 + 2), 16);
+    }
+    var reader = jspb.BinaryReader.alloc(bytes);
+    reader.nextField();
+    assertEquals(expected, readField.call(reader));
+  }
+
+
+  /**
+   * Tests non-canonical redundant varint decoding.
+   */
+  it('testRedundantVarintFields', function() {
+    assertNotNull(jspb.BinaryReader.prototype.readUint32);
+    assertNotNull(jspb.BinaryReader.prototype.readUint64);
+    assertNotNull(jspb.BinaryReader.prototype.readSint32);
+    assertNotNull(jspb.BinaryReader.prototype.readSint64);
+
+    // uint32 and sint32 take no more than 5 bytes
+    // 08 - field prefix (type = 0 means varint)
+    doTestHexStringVarint_(
+      jspb.BinaryReader.prototype.readUint32,
+      12, '08 8C 80 80 80 00');
+
+    // 11 stands for -6 in zigzag encoding
+    doTestHexStringVarint_(
+      jspb.BinaryReader.prototype.readSint32,
+      -6, '08 8B 80 80 80 00');
+
+    // uint64 and sint64 take no more than 10 bytes
+    // 08 - field prefix (type = 0 means varint)
+    doTestHexStringVarint_(
+      jspb.BinaryReader.prototype.readUint64,
+      12, '08 8C 80 80 80 80 80 80 80 80 00');
+
+    // 11 stands for -6 in zigzag encoding
+    doTestHexStringVarint_(
+      jspb.BinaryReader.prototype.readSint64,
+      -6, '08 8B 80 80 80 80 80 80 80 80 00');
+  });
+
+
+  /**
+   * Tests 64-bit fields that are handled as strings.
+   */
+  it('testStringInt64Fields', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var testSignedData = [
+      '2730538252207801776',
+      '-2688470994844604560',
+      '3398529779486536359',
+      '3568577411627971000',
+      '272477188847484900',
+      '-6649058714086158188',
+      '-7695254765712060806',
+      '-4525541438037104029',
+      '-4993706538836508568',
+      '4990160321893729138'
+    ];
+    var testUnsignedData = [
+      '7822732630241694882',
+      '6753602971916687352',
+      '2399935075244442116',
+      '8724292567325338867',
+      '16948784802625696584',
+      '4136275908516066934',
+      '3575388346793700364',
+      '5167142028379259461',
+      '1557573948689737699',
+      '17100725280812548567'
+    ];
+
+    for (var i = 0; i < testSignedData.length; i++) {
+      writer.writeInt64String(2 * i + 1, testSignedData[i]);
+      writer.writeUint64String(2 * i + 2, testUnsignedData[i]);
+    }
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    for (var i = 0; i < testSignedData.length; i++) {
+      reader.nextField();
+      assertEquals(2 * i + 1, reader.getFieldNumber());
+      assertEquals(testSignedData[i], reader.readInt64String());
+      reader.nextField();
+      assertEquals(2 * i + 2, reader.getFieldNumber());
+      assertEquals(testUnsignedData[i], reader.readUint64String());
+    }
+  });
+
+
+  /**
+   * Tests fields that use zigzag encoding.
+   */
+  it('testZigzagFields', function() {
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readSint32,
+        jspb.BinaryWriter.prototype.writeSint32,
+        1, -Math.pow(2, 31), Math.pow(2, 31) - 1, Math.round);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readSint64,
+        jspb.BinaryWriter.prototype.writeSint64,
+        1, -Math.pow(2, 63), Math.pow(2, 63) - 513, Math.round);
+  });
+
+
+  /**
+   * Tests fields that use fixed-length encoding.
+   */
+  it('testFixedFields', function() {
+    doTestUnsignedField_(
+        jspb.BinaryReader.prototype.readFixed32,
+        jspb.BinaryWriter.prototype.writeFixed32,
+        1, Math.pow(2, 32) - 1, Math.round);
+
+    doTestUnsignedField_(
+        jspb.BinaryReader.prototype.readFixed64,
+        jspb.BinaryWriter.prototype.writeFixed64,
+        1, Math.pow(2, 64) - 1025, Math.round);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readSfixed32,
+        jspb.BinaryWriter.prototype.writeSfixed32,
+        1, -Math.pow(2, 31), Math.pow(2, 31) - 1, Math.round);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readSfixed64,
+        jspb.BinaryWriter.prototype.writeSfixed64,
+        1, -Math.pow(2, 63), Math.pow(2, 63) - 513, Math.round);
+  });
+
+
+  /**
+   * Tests floating point fields.
+   */
+  it('testFloatFields', function() {
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readFloat,
+        jspb.BinaryWriter.prototype.writeFloat,
+        jspb.BinaryConstants.FLOAT32_MIN,
+        -jspb.BinaryConstants.FLOAT32_MAX,
+        jspb.BinaryConstants.FLOAT32_MAX,
+        truncate);
+
+    doTestSignedField_(
+        jspb.BinaryReader.prototype.readDouble,
+        jspb.BinaryWriter.prototype.writeDouble,
+        jspb.BinaryConstants.FLOAT64_EPS * 10,
+        -jspb.BinaryConstants.FLOAT64_MIN,
+        jspb.BinaryConstants.FLOAT64_MIN,
+        function(x) { return x; });
+  });
+
+
+  /**
+   * Tests length-delimited string fields.
+   */
+  it('testStringFields', function() {
+    var s1 = 'The quick brown fox jumps over the lazy dog.';
+    var s2 = '人人生而自由，在尊嚴和權利上一律平等。';
+
+    var writer = new jspb.BinaryWriter();
+
+    writer.writeString(1, s1);
+    writer.writeString(2, s2);
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    assertEquals(s1, reader.readString());
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    assertEquals(s2, reader.readString());
+  });
+
+
+  /**
+   * Tests length-delimited byte fields.
+   */
+  it('testByteFields', function() {
+    var message = [];
+    var lowerLimit = 1;
+    var upperLimit = 256;
+    var scale = 1.1;
+
+    var writer = new jspb.BinaryWriter();
+
+    for (var cursor = lowerLimit; cursor < upperLimit; cursor *= 1.1) {
+      var len = Math.round(cursor);
+      var bytes = [];
+      for (var i = 0; i < len; i++) bytes.push(i % 256);
+
+      writer.writeBytes(len, bytes);
+    }
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    for (var cursor = lowerLimit; reader.nextField(); cursor *= 1.1) {
+      var len = Math.round(cursor);
+      if (len != reader.getFieldNumber()) throw 'fail!';
+
+      var bytes = reader.readBytes();
+      if (len != bytes.length) throw 'fail!';
+      for (var i = 0; i < bytes.length; i++) {
+        if (i % 256 != bytes[i]) throw 'fail!';
+      }
+    }
+  });
+
+
+  /**
+   * Tests nested messages.
+   */
+  it('testNesting', function() {
+    var writer = new jspb.BinaryWriter();
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+
+    writer.writeInt32(1, 100);
+
+    // Add one message with 3 int fields.
+    writer.writeMessage(2, dummyMessage, function() {
+      writer.writeInt32(3, 300);
+      writer.writeInt32(4, 400);
+      writer.writeInt32(5, 500);
+    });
+
+    // Add one empty message.
+    writer.writeMessage(6, dummyMessage, goog.nullFunction);
+
+    writer.writeInt32(7, 700);
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    // Validate outermost message.
+
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    assertEquals(100, reader.readInt32());
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    reader.readMessage(dummyMessage, function() {
+      // Validate embedded message 1.
+      reader.nextField();
+      assertEquals(3, reader.getFieldNumber());
+      assertEquals(300, reader.readInt32());
+
+      reader.nextField();
+      assertEquals(4, reader.getFieldNumber());
+      assertEquals(400, reader.readInt32());
+
+      reader.nextField();
+      assertEquals(5, reader.getFieldNumber());
+      assertEquals(500, reader.readInt32());
+
+      assertEquals(false, reader.nextField());
+    });
+
+    reader.nextField();
+    assertEquals(6, reader.getFieldNumber());
+    reader.readMessage(dummyMessage, function() {
+      // Validate embedded message 2.
+
+      assertEquals(false, reader.nextField());
+    });
+
+    reader.nextField();
+    assertEquals(7, reader.getFieldNumber());
+    assertEquals(700, reader.readInt32());
+
+    assertEquals(false, reader.nextField());
+  });
+
+  /**
+   * Tests skipping fields of each type by interleaving them with sentinel
+   * values and skipping everything that's not a sentinel.
+   */
+  it('testSkipField', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var sentinel = 123456789;
+
+    // Write varint fields of different sizes.
+    writer.writeInt32(1, sentinel);
+    writer.writeInt32(1, 1);
+    writer.writeInt32(1, 1000);
+    writer.writeInt32(1, 1000000);
+    writer.writeInt32(1, 1000000000);
+
+    // Write fixed 64-bit encoded fields.
+    writer.writeInt32(2, sentinel);
+    writer.writeDouble(2, 1);
+    writer.writeFixed64(2, 1);
+    writer.writeSfixed64(2, 1);
+
+    // Write fixed 32-bit encoded fields.
+    writer.writeInt32(3, sentinel);
+    writer.writeFloat(3, 1);
+    writer.writeFixed32(3, 1);
+    writer.writeSfixed32(3, 1);
+
+    // Write delimited fields.
+    writer.writeInt32(4, sentinel);
+    writer.writeBytes(4, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
+    writer.writeString(4, 'The quick brown fox jumps over the lazy dog');
+
+    // Write a group with a nested group inside.
+    writer.writeInt32(5, sentinel);
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+    writer.writeGroup(5, dummyMessage, function() {
+      writer.writeInt64(42, 42);
+      writer.writeGroup(6, dummyMessage, function() {
+        writer.writeInt64(84, 42);
+      });
+    });
+
+    // Write final sentinel.
+    writer.writeInt32(6, sentinel);
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    function skip(field, count) {
+      for (var i = 0; i < count; i++) {
+        reader.nextField();
+        if (field != reader.getFieldNumber()) throw 'fail!';
+        reader.skipField();
+      }
+    }
+
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    assertEquals(sentinel, reader.readInt32());
+    skip(1, 4);
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    assertEquals(sentinel, reader.readInt32());
+    skip(2, 3);
+
+    reader.nextField();
+    assertEquals(3, reader.getFieldNumber());
+    assertEquals(sentinel, reader.readInt32());
+    skip(3, 3);
+
+    reader.nextField();
+    assertEquals(4, reader.getFieldNumber());
+    assertEquals(sentinel, reader.readInt32());
+    skip(4, 2);
+
+    reader.nextField();
+    assertEquals(5, reader.getFieldNumber());
+    assertEquals(sentinel, reader.readInt32());
+    skip(5, 1);
+
+    reader.nextField();
+    assertEquals(6, reader.getFieldNumber());
+    assertEquals(sentinel, reader.readInt32());
+  });
+
+
+  /**
+   * Tests packed fields.
+   */
+  it('testPackedFields', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var sentinel = 123456789;
+
+    var unsignedData = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    var signedData = [-1, 2, -3, 4, -5, 6, -7, 8, -9, 10];
+    var floatData = [1.1, 2.2, 3.3, 4.4, 5.5, 6.6, 7.7, 8.8, 9.9, 10.10];
+    var doubleData = [1.1, 2.2, 3.3, 4.4, 5.5, 6.6, 7.7, 8.8, 9.9, 10.10];
+    var boolData = [true, false, true, true, false, false, true, false];
+
+    for (var i = 0; i < floatData.length; i++) {
+      floatData[i] = truncate(floatData[i]);
+    }
+
+    writer.writeInt32(1, sentinel);
+
+    writer.writePackedInt32(2, signedData);
+    writer.writePackedInt64(2, signedData);
+    writer.writePackedUint32(2, unsignedData);
+    writer.writePackedUint64(2, unsignedData);
+    writer.writePackedSint32(2, signedData);
+    writer.writePackedSint64(2, signedData);
+    writer.writePackedFixed32(2, unsignedData);
+    writer.writePackedFixed64(2, unsignedData);
+    writer.writePackedSfixed32(2, signedData);
+    writer.writePackedSfixed64(2, signedData);
+    writer.writePackedFloat(2, floatData);
+    writer.writePackedDouble(2, doubleData);
+    writer.writePackedBool(2, boolData);
+    writer.writePackedEnum(2, unsignedData);
+
+    writer.writeInt32(3, sentinel);
+
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    reader.nextField();
+    assertEquals(sentinel, reader.readInt32());
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedInt32(), signedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedInt64(), signedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedUint32(), unsignedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedUint64(), unsignedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedSint32(), signedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedSint64(), signedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedFixed32(), unsignedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedFixed64(), unsignedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedSfixed32(), signedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedSfixed64(), signedData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedFloat(), floatData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedDouble(), doubleData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedBool(), boolData);
+
+    reader.nextField();
+    assertElementsEquals(reader.readPackedEnum(), unsignedData);
+
+    reader.nextField();
+    assertEquals(sentinel, reader.readInt32());
+  });
+
+
+  /**
+   * Byte blobs inside nested messages should always have their byte offset set
+   * relative to the start of the outermost blob, not the start of their parent
+   * blob.
+   */
+  it('testNestedBlobs', function() {
+    // Create a proto consisting of two nested messages, with the inner one
+    // containing a blob of bytes.
+
+    var fieldTag = (1 << 3) | jspb.BinaryConstants.WireType.DELIMITED;
+    var blob = [1, 2, 3, 4, 5];
+    var writer = new jspb.BinaryWriter();
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+
+    writer.writeMessage(1, dummyMessage, function() {
+      writer.writeMessage(1, dummyMessage, function() {
+        writer.writeBytes(1, blob);
+      });
+    });
+
+    // Peel off the outer two message layers. Each layer should have two bytes
+    // of overhead, one for the field tag and one for the length of the inner
+    // blob.
+
+    var decoder1 = new jspb.BinaryDecoder(writer.getResultBuffer());
+    assertEquals(fieldTag, decoder1.readUnsignedVarint32());
+    assertEquals(blob.length + 4, decoder1.readUnsignedVarint32());
+
+    var decoder2 = new jspb.BinaryDecoder(decoder1.readBytes(blob.length + 4));
+    assertEquals(fieldTag, decoder2.readUnsignedVarint32());
+    assertEquals(blob.length + 2, decoder2.readUnsignedVarint32());
+
+    assertEquals(fieldTag, decoder2.readUnsignedVarint32());
+    assertEquals(blob.length, decoder2.readUnsignedVarint32());
+    var bytes = decoder2.readBytes(blob.length);
+
+    assertElementsEquals(bytes, blob);
+  });
+
+
+  /**
+   * Tests read callbacks.
+   */
+  it('testReadCallbacks', function() {
+    var writer = new jspb.BinaryWriter();
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+
+    // Add an int, a submessage, and another int.
+    writer.writeInt32(1, 100);
+
+    writer.writeMessage(2, dummyMessage, function() {
+      writer.writeInt32(3, 300);
+      writer.writeInt32(4, 400);
+      writer.writeInt32(5, 500);
+    });
+
+    writer.writeInt32(7, 700);
+
+    // Create the reader and register a custom read callback.
+    var reader = jspb.BinaryReader.alloc(writer.getResultBuffer());
+
+    /**
+     * @param {!jspb.BinaryReader} reader
+     * @return {*}
+     */
+    function readCallback(reader) {
+      reader.nextField();
+      assertEquals(3, reader.getFieldNumber());
+      assertEquals(300, reader.readInt32());
+
+      reader.nextField();
+      assertEquals(4, reader.getFieldNumber());
+      assertEquals(400, reader.readInt32());
+
+      reader.nextField();
+      assertEquals(5, reader.getFieldNumber());
+      assertEquals(500, reader.readInt32());
+
+      assertEquals(false, reader.nextField());
+    };
+
+    reader.registerReadCallback('readCallback', readCallback);
+
+    // Read the container message.
+    reader.nextField();
+    assertEquals(1, reader.getFieldNumber());
+    assertEquals(100, reader.readInt32());
+
+    reader.nextField();
+    assertEquals(2, reader.getFieldNumber());
+    reader.readMessage(dummyMessage, function() {
+      // Decode the embedded message using the registered callback.
+      reader.runReadCallback('readCallback');
+    });
+
+    reader.nextField();
+    assertEquals(7, reader.getFieldNumber());
+    assertEquals(700, reader.readInt32());
+
+    assertEquals(false, reader.nextField());
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/binary/utils_test.js b/js/compatibility_tests/v3.1.0/binary/utils_test.js
new file mode 100644
index 00000000..d27e5ea2
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/binary/utils_test.js
@@ -0,0 +1,668 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/**
+ * @fileoverview Test cases for jspb's helper functions.
+ *
+ * Test suite is written using Jasmine -- see http://jasmine.github.io/
+ *
+ * @author aappleby@google.com (Austin Appleby)
+ */
+
+goog.require('goog.crypt.base64');
+goog.require('goog.testing.asserts');
+goog.require('jspb.BinaryConstants');
+goog.require('jspb.BinaryWriter');
+goog.require('jspb.utils');
+
+
+/**
+ * @param {number} x
+ * @return {number}
+ */
+function truncate(x) {
+  var temp = new Float32Array(1);
+  temp[0] = x;
+  return temp[0];
+}
+
+
+/**
+ * Converts an 64-bit integer in split representation to a 64-bit hash string
+ * (8 bits encoded per character).
+ * @param {number} bitsLow The low 32 bits of the split 64-bit integer.
+ * @param {number} bitsHigh The high 32 bits of the split 64-bit integer.
+ * @return {string} The encoded hash string, 8 bits per character.
+ */
+function toHashString(bitsLow, bitsHigh) {
+  return String.fromCharCode((bitsLow >>> 0) & 0xFF,
+                             (bitsLow >>> 8) & 0xFF,
+                             (bitsLow >>> 16) & 0xFF,
+                             (bitsLow >>> 24) & 0xFF,
+                             (bitsHigh >>> 0) & 0xFF,
+                             (bitsHigh >>> 8) & 0xFF,
+                             (bitsHigh >>> 16) & 0xFF,
+                             (bitsHigh >>> 24) & 0xFF);
+}
+
+
+describe('binaryUtilsTest', function() {
+  /**
+   * Tests lossless binary-to-decimal conversion.
+   */
+  it('testDecimalConversion', function() {
+    // Check some magic numbers.
+    var result =
+        jspb.utils.joinUnsignedDecimalString(0x89e80001, 0x8ac72304);
+    assertEquals('10000000000000000001', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0xacd05f15, 0x1b69b4b);
+    assertEquals('123456789123456789', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0xeb1f0ad2, 0xab54a98c);
+    assertEquals('12345678901234567890', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0xe3b70cb1, 0x891087b8);
+    assertEquals('9876543210987654321', result);
+
+    // Check limits.
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x00000000);
+    assertEquals('0', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0xFFFFFFFF, 0xFFFFFFFF);
+    assertEquals('18446744073709551615', result);
+
+    // Check each bit of the low dword.
+    for (var i = 0; i < 32; i++) {
+      var low = (1 << i) >>> 0;
+      result = jspb.utils.joinUnsignedDecimalString(low, 0);
+      assertEquals('' + Math.pow(2, i), result);
+    }
+
+    // Check the first 20 bits of the high dword.
+    for (var i = 0; i < 20; i++) {
+      var high = (1 << i) >>> 0;
+      result = jspb.utils.joinUnsignedDecimalString(0, high);
+      assertEquals('' + Math.pow(2, 32 + i), result);
+    }
+
+    // V8's internal double-to-string conversion is inaccurate for values above
+    // 2^52, even if they're representable integers - check the rest of the bits
+    // manually against the correct string representations of 2^N.
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x00100000);
+    assertEquals('4503599627370496', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x00200000);
+    assertEquals('9007199254740992', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x00400000);
+    assertEquals('18014398509481984', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x00800000);
+    assertEquals('36028797018963968', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x01000000);
+    assertEquals('72057594037927936', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x02000000);
+    assertEquals('144115188075855872', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x04000000);
+    assertEquals('288230376151711744', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x08000000);
+    assertEquals('576460752303423488', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x10000000);
+    assertEquals('1152921504606846976', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x20000000);
+    assertEquals('2305843009213693952', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x40000000);
+    assertEquals('4611686018427387904', result);
+
+    result = jspb.utils.joinUnsignedDecimalString(0x00000000, 0x80000000);
+    assertEquals('9223372036854775808', result);
+  });
+
+
+  /**
+   * Going from hash strings to decimal strings should also be lossless.
+   */
+  it('testHashToDecimalConversion', function() {
+    var result;
+    var convert = jspb.utils.hash64ToDecimalString;
+
+    result = convert(toHashString(0x00000000, 0x00000000), false);
+    assertEquals('0', result);
+
+    result = convert(toHashString(0x00000000, 0x00000000), true);
+    assertEquals('0', result);
+
+    result = convert(toHashString(0xFFFFFFFF, 0xFFFFFFFF), false);
+    assertEquals('18446744073709551615', result);
+
+    result = convert(toHashString(0xFFFFFFFF, 0xFFFFFFFF), true);
+    assertEquals('-1', result);
+
+    result = convert(toHashString(0x00000000, 0x80000000), false);
+    assertEquals('9223372036854775808', result);
+
+    result = convert(toHashString(0x00000000, 0x80000000), true);
+    assertEquals('-9223372036854775808', result);
+
+    result = convert(toHashString(0xacd05f15, 0x01b69b4b), false);
+    assertEquals('123456789123456789', result);
+
+    result = convert(toHashString(~0xacd05f15 + 1, ~0x01b69b4b), true);
+    assertEquals('-123456789123456789', result);
+
+    // And converting arrays of hashes should work the same way.
+    result = jspb.utils.hash64ArrayToDecimalStrings([
+      toHashString(0xFFFFFFFF, 0xFFFFFFFF),
+      toHashString(0x00000000, 0x80000000),
+      toHashString(0xacd05f15, 0x01b69b4b)], false);
+    assertEquals(3, result.length);
+    assertEquals('18446744073709551615', result[0]);
+    assertEquals('9223372036854775808', result[1]);
+    assertEquals('123456789123456789', result[2]);
+  });
+
+  /*
+   * Going from decimal strings to hash strings should be lossless.
+   */
+  it('testDecimalToHashConversion', function() {
+    var result;
+    var convert = jspb.utils.decimalStringToHash64;
+
+    result = convert('0');
+    assertEquals(String.fromCharCode.apply(null,
+      [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]), result);
+
+    result = convert('-1');
+    assertEquals(String.fromCharCode.apply(null,
+      [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]), result);
+
+    result = convert('18446744073709551615');
+    assertEquals(String.fromCharCode.apply(null,
+      [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]), result);
+
+    result = convert('9223372036854775808');
+    assertEquals(String.fromCharCode.apply(null,
+      [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80]), result);
+
+    result = convert('-9223372036854775808');
+    assertEquals(String.fromCharCode.apply(null,
+      [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80]), result);
+
+    result = convert('123456789123456789');
+    assertEquals(String.fromCharCode.apply(null,
+      [0x15, 0x5F, 0xD0, 0xAC, 0x4B, 0x9B, 0xB6, 0x01]), result);
+
+    result = convert('-123456789123456789');
+    assertEquals(String.fromCharCode.apply(null,
+      [0xEB, 0xA0, 0x2F, 0x53, 0xB4, 0x64, 0x49, 0xFE]), result);
+  });
+
+  /**
+   * Going from hash strings to hex strings should be lossless.
+   */
+  it('testHashToHexConversion', function() {
+    var result;
+    var convert = jspb.utils.hash64ToHexString;
+
+    result = convert(toHashString(0x00000000, 0x00000000));
+    assertEquals('0x0000000000000000', result);
+
+    result = convert(toHashString(0xFFFFFFFF, 0xFFFFFFFF));
+    assertEquals('0xffffffffffffffff', result);
+
+    result = convert(toHashString(0x12345678, 0x9ABCDEF0));
+    assertEquals('0x9abcdef012345678', result);
+  });
+
+
+  /**
+   * Going from hex strings to hash strings should be lossless.
+   */
+  it('testHexToHashConversion', function() {
+    var result;
+    var convert = jspb.utils.hexStringToHash64;
+
+    result = convert('0x0000000000000000');
+    assertEquals(String.fromCharCode.apply(null,
+        [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]), result);
+
+    result = convert('0xffffffffffffffff');
+    assertEquals(String.fromCharCode.apply(null,
+        [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]), result);
+
+    // Hex string is big-endian, hash string is little-endian.
+    result = convert('0x123456789ABCDEF0');
+    assertEquals(String.fromCharCode.apply(null,
+        [0xF0, 0xDE, 0xBC, 0x9A, 0x78, 0x56, 0x34, 0x12]), result);
+
+    // Capitalization should not matter.
+    result = convert('0x0000abcdefABCDEF');
+    assertEquals(String.fromCharCode.apply(null,
+        [0xEF, 0xCD, 0xAB, 0xEF, 0xCD, 0xAB, 0x00, 0x00]), result);
+  });
+
+
+  /**
+   * Going from numbers to hash strings should be lossless for up to 53 bits of
+   * precision.
+   */
+  it('testNumberToHashConversion', function() {
+    var result;
+    var convert = jspb.utils.numberToHash64;
+
+    result = convert(0x0000000000000);
+    assertEquals('0x0000000000000000', jspb.utils.hash64ToHexString(result));
+
+    result = convert(0xFFFFFFFFFFFFF);
+    assertEquals('0x000fffffffffffff', jspb.utils.hash64ToHexString(result));
+
+    result = convert(0x123456789ABCD);
+    assertEquals('0x000123456789abcd', jspb.utils.hash64ToHexString(result));
+
+    result = convert(0xDCBA987654321);
+    assertEquals('0x000dcba987654321', jspb.utils.hash64ToHexString(result));
+
+    // 53 bits of precision should not be truncated.
+    result = convert(0x10000000000001);
+    assertEquals('0x0010000000000001', jspb.utils.hash64ToHexString(result));
+
+    // 54 bits of precision should be truncated.
+    result = convert(0x20000000000001);
+    assertNotEquals(
+        '0x0020000000000001', jspb.utils.hash64ToHexString(result));
+  });
+
+
+  /**
+   * Sanity check the behavior of Javascript's strings when doing funny things
+   * with unicode characters.
+   */
+  it('sanityCheckUnicodeStrings', function() {
+    var strings = new Array(65536);
+
+    // All possible unsigned 16-bit values should be storable in a string, they
+    // shouldn't do weird things with the length of the string, and they should
+    // come back out of the string unchanged.
+    for (var i = 0; i < 65536; i++) {
+      strings[i] = 'a' + String.fromCharCode(i) + 'a';
+      if (3 != strings[i].length) throw 'fail!';
+      if (i != strings[i].charCodeAt(1)) throw 'fail!';
+    }
+
+    // Each unicode character should compare equal to itself and not equal to a
+    // different unicode character.
+    for (var i = 0; i < 65536; i++) {
+      if (strings[i] != strings[i]) throw 'fail!';
+      if (strings[i] == strings[(i + 1) % 65536]) throw 'fail!';
+    }
+  });
+
+
+  /**
+   * Tests conversion from 32-bit floating point numbers to split64 numbers.
+   */
+  it('testFloat32ToSplit64', function() {
+    var f32_eps = jspb.BinaryConstants.FLOAT32_EPS;
+    var f32_min = jspb.BinaryConstants.FLOAT32_MIN;
+    var f32_max = jspb.BinaryConstants.FLOAT32_MAX;
+
+    // NaN.
+    jspb.utils.splitFloat32(NaN);
+    if (!isNaN(jspb.utils.joinFloat32(jspb.utils.split64Low,
+                                      jspb.utils.split64High))) {
+      throw 'fail!';
+    }
+
+    /**
+     * @param {number} x
+     * @param {number=} opt_bits
+     */
+    function test(x, opt_bits) {
+      jspb.utils.splitFloat32(x);
+      if (goog.isDef(opt_bits)) {
+        if (opt_bits != jspb.utils.split64Low) throw 'fail!';
+      }
+      if (truncate(x) != jspb.utils.joinFloat32(jspb.utils.split64Low,
+          jspb.utils.split64High)) {
+        throw 'fail!';
+      }
+    }
+
+    // Positive and negative infinity.
+    test(Infinity, 0x7f800000);
+    test(-Infinity, 0xff800000);
+
+    // Positive and negative zero.
+    test(0, 0x00000000);
+    test(-0, 0x80000000);
+
+    // Positive and negative epsilon.
+    test(f32_eps, 0x00000001);
+    test(-f32_eps, 0x80000001);
+
+    // Positive and negative min.
+    test(f32_min, 0x00800000);
+    test(-f32_min, 0x80800000);
+
+    // Positive and negative max.
+    test(f32_max, 0x7F7FFFFF);
+    test(-f32_max, 0xFF7FFFFF);
+
+    // Various positive values.
+    var cursor = f32_eps * 10;
+    while (cursor != Infinity) {
+      test(cursor);
+      cursor *= 1.1;
+    }
+
+    // Various negative values.
+    cursor = -f32_eps * 10;
+    while (cursor != -Infinity) {
+      test(cursor);
+      cursor *= 1.1;
+    }
+  });
+
+
+  /**
+   * Tests conversion from 64-bit floating point numbers to split64 numbers.
+   */
+  it('testFloat64ToSplit64', function() {
+    var f64_eps = jspb.BinaryConstants.FLOAT64_EPS;
+    var f64_min = jspb.BinaryConstants.FLOAT64_MIN;
+    var f64_max = jspb.BinaryConstants.FLOAT64_MAX;
+
+    // NaN.
+    jspb.utils.splitFloat64(NaN);
+    if (!isNaN(jspb.utils.joinFloat64(jspb.utils.split64Low,
+        jspb.utils.split64High))) {
+      throw 'fail!';
+    }
+
+    /**
+     * @param {number} x
+     * @param {number=} opt_highBits
+     * @param {number=} opt_lowBits
+     */
+    function test(x, opt_highBits, opt_lowBits) {
+      jspb.utils.splitFloat64(x);
+      if (goog.isDef(opt_highBits)) {
+        if (opt_highBits != jspb.utils.split64High) throw 'fail!';
+      }
+      if (goog.isDef(opt_lowBits)) {
+        if (opt_lowBits != jspb.utils.split64Low) throw 'fail!';
+      }
+      if (x != jspb.utils.joinFloat64(jspb.utils.split64Low,
+          jspb.utils.split64High)) {
+        throw 'fail!';
+      }
+    }
+
+    // Positive and negative infinity.
+    test(Infinity, 0x7ff00000, 0x00000000);
+    test(-Infinity, 0xfff00000, 0x00000000);
+
+    // Positive and negative zero.
+    test(0, 0x00000000, 0x00000000);
+    test(-0, 0x80000000, 0x00000000);
+
+    // Positive and negative epsilon.
+    test(f64_eps, 0x00000000, 0x00000001);
+    test(-f64_eps, 0x80000000, 0x00000001);
+
+    // Positive and negative min.
+    test(f64_min, 0x00100000, 0x00000000);
+    test(-f64_min, 0x80100000, 0x00000000);
+
+    // Positive and negative max.
+    test(f64_max, 0x7FEFFFFF, 0xFFFFFFFF);
+    test(-f64_max, 0xFFEFFFFF, 0xFFFFFFFF);
+
+    // Various positive values.
+    var cursor = f64_eps * 10;
+    while (cursor != Infinity) {
+      test(cursor);
+      cursor *= 1.1;
+    }
+
+    // Various negative values.
+    cursor = -f64_eps * 10;
+    while (cursor != -Infinity) {
+      test(cursor);
+      cursor *= 1.1;
+    }
+  });
+
+
+  /**
+   * Tests counting packed varints.
+   */
+  it('testCountVarints', function() {
+    var values = [];
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      values.push(Math.floor(i));
+    }
+
+    var writer = new jspb.BinaryWriter();
+    writer.writePackedUint64(1, values);
+
+    var buffer = new Uint8Array(writer.getResultBuffer());
+
+    // We should have two more varints than we started with - one for the field
+    // tag, one for the packed length.
+    assertEquals(values.length + 2,
+                 jspb.utils.countVarints(buffer, 0, buffer.length));
+  });
+
+
+  /**
+   * Tests counting matching varint fields.
+   */
+  it('testCountVarintFields', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var count = 0;
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      writer.writeUint64(1, Math.floor(i));
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    var buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countVarintFields(buffer, 0, buffer.length, 1));
+
+    writer = new jspb.BinaryWriter();
+
+    count = 0;
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      writer.writeUint64(123456789, Math.floor(i));
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countVarintFields(buffer, 0, buffer.length, 123456789));
+  });
+
+
+  /**
+   * Tests counting matching fixed32 fields.
+   */
+  it('testCountFixed32Fields', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var count = 0;
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      writer.writeFixed32(1, Math.floor(i));
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    var buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countFixed32Fields(buffer, 0, buffer.length, 1));
+
+    writer = new jspb.BinaryWriter();
+
+    count = 0;
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      writer.writeFixed32(123456789, Math.floor(i));
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countFixed32Fields(buffer, 0, buffer.length, 123456789));
+  });
+
+
+  /**
+   * Tests counting matching fixed64 fields.
+   */
+  it('testCountFixed64Fields', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var count = 0;
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      writer.writeDouble(1, i);
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    var buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countFixed64Fields(buffer, 0, buffer.length, 1));
+
+    writer = new jspb.BinaryWriter();
+
+    count = 0;
+    for (var i = 1; i < 1000000000; i *= 1.1) {
+      writer.writeDouble(123456789, i);
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countFixed64Fields(buffer, 0, buffer.length, 123456789));
+  });
+
+
+  /**
+   * Tests counting matching delimited fields.
+   */
+  it('testCountDelimitedFields', function() {
+    var writer = new jspb.BinaryWriter();
+
+    var count = 0;
+    for (var i = 1; i < 1000; i *= 1.1) {
+      writer.writeBytes(1, [Math.floor(i)]);
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    var buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countDelimitedFields(buffer, 0, buffer.length, 1));
+
+    writer = new jspb.BinaryWriter();
+
+    count = 0;
+    for (var i = 1; i < 1000; i *= 1.1) {
+      writer.writeBytes(123456789, [Math.floor(i)]);
+      count++;
+    }
+    writer.writeString(2, 'terminator');
+
+    buffer = new Uint8Array(writer.getResultBuffer());
+    assertEquals(count,
+        jspb.utils.countDelimitedFields(buffer, 0, buffer.length, 123456789));
+  });
+
+
+  /**
+   * Tests byte format for debug strings.
+   */
+  it('testDebugBytesToTextFormat', function() {
+    assertEquals('""', jspb.utils.debugBytesToTextFormat(null));
+    assertEquals('"\\x00\\x10\\xff"',
+        jspb.utils.debugBytesToTextFormat([0, 16, 255]));
+  });
+
+
+  /**
+   * Tests converting byte blob sources into byte blobs.
+   */
+  it('testByteSourceToUint8Array', function() {
+    var convert = jspb.utils.byteSourceToUint8Array;
+
+    var sourceData = [];
+    for (var i = 0; i < 256; i++) {
+      sourceData.push(i);
+    }
+
+    var sourceBytes = new Uint8Array(sourceData);
+    var sourceBuffer = sourceBytes.buffer;
+    var sourceBase64 = goog.crypt.base64.encodeByteArray(sourceData);
+    var sourceString = String.fromCharCode.apply(null, sourceData);
+
+    function check(result) {
+      assertEquals(Uint8Array, result.constructor);
+      assertEquals(sourceData.length, result.length);
+      for (var i = 0; i < result.length; i++) {
+        assertEquals(sourceData[i], result[i]);
+      }
+    }
+
+    // Converting Uint8Arrays into Uint8Arrays should be a no-op.
+    assertEquals(sourceBytes, convert(sourceBytes));
+
+    // Converting Array.<numbers> into Uint8Arrays should work.
+    check(convert(sourceData));
+
+    // Converting ArrayBuffers into Uint8Arrays should work.
+    check(convert(sourceBuffer));
+
+    // Converting base64-encoded strings into Uint8Arrays should work.
+    check(convert(sourceBase64));
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/binary/writer_test.js b/js/compatibility_tests/v3.1.0/binary/writer_test.js
new file mode 100644
index 00000000..d5dadb41
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/binary/writer_test.js
@@ -0,0 +1,122 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/**
+ * @fileoverview Test cases for jspb's binary protocol buffer writer. In
+ * practice BinaryWriter is used to drive the Decoder and Reader test cases,
+ * so only writer-specific tests are here.
+ *
+ * Test suite is written using Jasmine -- see http://jasmine.github.io/
+ *
+ * @author aappleby@google.com (Austin Appleby)
+ */
+
+goog.require('goog.crypt');
+goog.require('goog.testing.asserts');
+goog.require('jspb.BinaryWriter');
+
+
+/**
+ * @param {function()} func This function should throw an error when run.
+ */
+function assertFails(func) {
+  var e = assertThrows(func);
+  //assertNotNull(e.toString().match(/Error/));
+}
+
+
+describe('binaryWriterTest', function() {
+  /**
+   * Verifies that misuse of the writer class triggers assertions.
+   */
+  it('testWriteErrors', function() {
+    // Submessages with invalid field indices should assert.
+    var writer = new jspb.BinaryWriter();
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+
+    assertFails(function() {
+      writer.writeMessage(-1, dummyMessage, goog.nullFunction);
+    });
+
+    // Writing invalid field indices should assert.
+    writer = new jspb.BinaryWriter();
+    assertFails(function() {writer.writeUint64(-1, 1);});
+
+    // Writing out-of-range field values should assert.
+    writer = new jspb.BinaryWriter();
+
+    assertFails(function() {writer.writeInt32(1, -Infinity);});
+    assertFails(function() {writer.writeInt32(1, Infinity);});
+
+    assertFails(function() {writer.writeInt64(1, -Infinity);});
+    assertFails(function() {writer.writeInt64(1, Infinity);});
+
+    assertFails(function() {writer.writeUint32(1, -1);});
+    assertFails(function() {writer.writeUint32(1, Infinity);});
+
+    assertFails(function() {writer.writeUint64(1, -1);});
+    assertFails(function() {writer.writeUint64(1, Infinity);});
+
+    assertFails(function() {writer.writeSint32(1, -Infinity);});
+    assertFails(function() {writer.writeSint32(1, Infinity);});
+
+    assertFails(function() {writer.writeSint64(1, -Infinity);});
+    assertFails(function() {writer.writeSint64(1, Infinity);});
+
+    assertFails(function() {writer.writeFixed32(1, -1);});
+    assertFails(function() {writer.writeFixed32(1, Infinity);});
+
+    assertFails(function() {writer.writeFixed64(1, -1);});
+    assertFails(function() {writer.writeFixed64(1, Infinity);});
+
+    assertFails(function() {writer.writeSfixed32(1, -Infinity);});
+    assertFails(function() {writer.writeSfixed32(1, Infinity);});
+
+    assertFails(function() {writer.writeSfixed64(1, -Infinity);});
+    assertFails(function() {writer.writeSfixed64(1, Infinity);});
+  });
+
+
+  /**
+   * Basic test of retrieving the result as a Uint8Array buffer
+   */
+  it('testGetResultBuffer', function() {
+    var expected = '0864120b48656c6c6f20776f726c641a0301020320c801';
+
+    var writer = new jspb.BinaryWriter();
+    writer.writeUint32(1, 100);
+    writer.writeString(2, 'Hello world');
+    writer.writeBytes(3, new Uint8Array([1, 2, 3]));
+    writer.writeUint32(4, 200);
+
+    var buffer = writer.getResultBuffer();
+    assertEquals(expected, goog.crypt.byteArrayToHex(buffer));
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/commonjs/test6/test6.proto b/js/compatibility_tests/v3.1.0/commonjs/test6/test6.proto
new file mode 100644
index 00000000..a060925f
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/commonjs/test6/test6.proto
@@ -0,0 +1,40 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2016 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.test.importing;
+
+message ImportedMessage {
+  string string_value = 1;
+}
diff --git a/js/compatibility_tests/v3.1.0/commonjs/test7/test7.proto b/js/compatibility_tests/v3.1.0/commonjs/test7/test7.proto
new file mode 100644
index 00000000..f5574a3d
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/commonjs/test7/test7.proto
@@ -0,0 +1,42 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2016 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.test.framing;
+
+import "test6/test6.proto";
+
+message FramingMessage {
+  jspb.test.importing.ImportedMessage imported_message = 1;
+}
diff --git a/js/compatibility_tests/v3.1.0/data.proto b/js/compatibility_tests/v3.1.0/data.proto
new file mode 100644
index 00000000..74a8a994
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/data.proto
@@ -0,0 +1,51 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Author: mwr@google.com (Mark Rawling)
+
+syntax = "proto2";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.test;
+
+// legacy data, must be nested
+message data {
+  message NestedData {
+    required string str = 1;
+  }
+}
+
+// new data, does not require nesting
+message UnnestedData {
+  required string str = 1;
+}
+
diff --git a/js/compatibility_tests/v3.1.0/debug_test.js b/js/compatibility_tests/v3.1.0/debug_test.js
new file mode 100644
index 00000000..702cc76e
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/debug_test.js
@@ -0,0 +1,105 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+goog.setTestOnly();
+
+goog.require('goog.testing.asserts');
+
+// CommonJS-LoadFromFile: google-protobuf
+goog.require('jspb.debug');
+
+// CommonJS-LoadFromFile: test_pb
+goog.require('proto.jspb.test.HasExtensions');
+goog.require('proto.jspb.test.IsExtension');
+goog.require('proto.jspb.test.Simple1');
+
+
+
+describe('debugTest', function() {
+  it('testSimple1', function() {
+    if (COMPILED) {
+      return;
+    }
+    var message = new proto.jspb.test.Simple1();
+    message.setAString('foo');
+    assertObjectEquals({
+      $name: 'proto.jspb.test.Simple1',
+      'aString': 'foo',
+      'aRepeatedStringList': []
+    }, jspb.debug.dump(message));
+
+    message.setABoolean(true);
+    message.setARepeatedStringList(['1', '2']);
+
+    assertObjectEquals({
+      $name: 'proto.jspb.test.Simple1',
+      'aString': 'foo',
+      'aRepeatedStringList': ['1', '2'],
+      'aBoolean': true
+    }, jspb.debug.dump(message));
+
+    message.clearAString();
+
+    assertObjectEquals({
+      $name: 'proto.jspb.test.Simple1',
+      'aRepeatedStringList': ['1', '2'],
+      'aBoolean': true
+    }, jspb.debug.dump(message));
+  });
+
+
+  it('testExtensions', function() {
+    if (COMPILED) {
+      return;
+    }
+    var extension = new proto.jspb.test.IsExtension();
+    extension.setExt1('ext1field');
+    var extendable = new proto.jspb.test.HasExtensions();
+    extendable.setStr1('v1');
+    extendable.setStr2('v2');
+    extendable.setStr3('v3');
+    extendable.setExtension(proto.jspb.test.IsExtension.extField, extension);
+
+    assertObjectEquals({
+      '$name': 'proto.jspb.test.HasExtensions',
+      'str1': 'v1',
+      'str2': 'v2',
+      'str3': 'v3',
+      '$extensions': {
+        'extField': {
+          '$name': 'proto.jspb.test.IsExtension',
+          'ext1': 'ext1field'
+        },
+        'repeatedSimpleList': []
+      }
+    }, jspb.debug.dump(extendable));
+  });
+
+});
diff --git a/js/compatibility_tests/v3.1.0/maps_test.js b/js/compatibility_tests/v3.1.0/maps_test.js
new file mode 100644
index 00000000..0d442f4f
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/maps_test.js
@@ -0,0 +1,301 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+goog.require('goog.testing.asserts');
+goog.require('goog.userAgent');
+
+// CommonJS-LoadFromFile: testbinary_pb proto.jspb.test
+goog.require('proto.jspb.test.MapValueEnum');
+goog.require('proto.jspb.test.MapValueMessage');
+goog.require('proto.jspb.test.TestMapFields');
+
+// CommonJS-LoadFromFile: test_pb proto.jspb.test
+goog.require('proto.jspb.test.MapValueMessageNoBinary');
+goog.require('proto.jspb.test.TestMapFieldsNoBinary');
+
+/**
+ * Helper: check that the given map has exactly this set of (sorted) entries.
+ * @param {!jspb.Map} map
+ * @param {!Array<!Array<?>>} entries
+ */
+function checkMapEquals(map, entries) {
+  var arr = map.toArray();
+  assertEquals(arr.length, entries.length);
+  for (var i = 0; i < arr.length; i++) {
+    assertElementsEquals(arr[i], entries[i]);
+  }
+}
+
+/**
+ * Converts an ES6 iterator to an array.
+ * @template T
+ * @param {!Iterator<T>} iter an iterator
+ * @return {!Array<T>}
+ */
+function toArray(iter) {
+  var arr = [];
+  while (true) {
+    var val = iter.next();
+    if (val.done) {
+      break;
+    }
+    arr.push(val.value);
+  }
+  return arr;
+}
+
+
+/**
+ * Helper: generate test methods for this TestMapFields class.
+ * @param {?} msgInfo
+ * @param {?} submessageCtor
+ * @param {!string} suffix
+ */
+function makeTests(msgInfo, submessageCtor, suffix) {
+  /**
+   * Helper: fill all maps on a TestMapFields.
+   * @param {?} msg
+   */
+  var fillMapFields = function(msg) {
+    msg.getMapStringStringMap().set('asdf', 'jkl;').set('key 2', 'hello world');
+    msg.getMapStringInt32Map().set('a', 1).set('b', -2);
+    msg.getMapStringInt64Map().set('c', 0x100000000).set('d', 0x200000000);
+    msg.getMapStringBoolMap().set('e', true).set('f', false);
+    msg.getMapStringDoubleMap().set('g', 3.14159).set('h', 2.71828);
+    msg.getMapStringEnumMap()
+        .set('i', proto.jspb.test.MapValueEnum.MAP_VALUE_BAR)
+        .set('j', proto.jspb.test.MapValueEnum.MAP_VALUE_BAZ);
+    msg.getMapStringMsgMap()
+        .set('k', new submessageCtor())
+        .set('l', new submessageCtor());
+    msg.getMapStringMsgMap().get('k').setFoo(42);
+    msg.getMapStringMsgMap().get('l').setFoo(84);
+    msg.getMapInt32StringMap().set(-1, 'a').set(42, 'b');
+    msg.getMapInt64StringMap().set(0x123456789abc, 'c').set(0xcba987654321, 'd');
+    msg.getMapBoolStringMap().set(false, 'e').set(true, 'f');
+  };
+
+  /**
+   * Helper: check all maps on a TestMapFields.
+   * @param {?} msg
+   */
+  var checkMapFields = function(msg) {
+    checkMapEquals(msg.getMapStringStringMap(), [
+          ['asdf', 'jkl;'],
+          ['key 2', 'hello world']
+    ]);
+    checkMapEquals(msg.getMapStringInt32Map(), [
+          ['a', 1],
+          ['b', -2]
+    ]);
+    checkMapEquals(msg.getMapStringInt64Map(), [
+          ['c', 0x100000000],
+          ['d', 0x200000000]
+    ]);
+    checkMapEquals(msg.getMapStringBoolMap(), [
+          ['e', true],
+          ['f', false]
+    ]);
+    checkMapEquals(msg.getMapStringDoubleMap(), [
+          ['g', 3.14159],
+          ['h', 2.71828]
+    ]);
+    checkMapEquals(msg.getMapStringEnumMap(), [
+          ['i', proto.jspb.test.MapValueEnum.MAP_VALUE_BAR],
+          ['j', proto.jspb.test.MapValueEnum.MAP_VALUE_BAZ]
+    ]);
+    checkMapEquals(msg.getMapInt32StringMap(), [
+          [-1, 'a'],
+          [42, 'b']
+    ]);
+    checkMapEquals(msg.getMapInt64StringMap(), [
+          [0x123456789abc, 'c'],
+          [0xcba987654321, 'd']
+    ]);
+    checkMapEquals(msg.getMapBoolStringMap(), [
+          [false, 'e'],
+          [true, 'f']
+    ]);
+
+    assertEquals(msg.getMapStringMsgMap().getLength(), 2);
+    assertEquals(msg.getMapStringMsgMap().get('k').getFoo(), 42);
+    assertEquals(msg.getMapStringMsgMap().get('l').getFoo(), 84);
+
+    var entries = toArray(msg.getMapStringMsgMap().entries());
+    assertEquals(entries.length, 2);
+    entries.forEach(function(entry) {
+      var key = entry[0];
+      var val = entry[1];
+      assert(val === msg.getMapStringMsgMap().get(key));
+    });
+
+    msg.getMapStringMsgMap().forEach(function(val, key) {
+      assert(val === msg.getMapStringMsgMap().get(key));
+    });
+  };
+
+  it('testMapStringStringField' + suffix, function() {
+    var msg = new msgInfo.constructor();
+    assertEquals(msg.getMapStringStringMap().getLength(), 0);
+    assertEquals(msg.getMapStringInt32Map().getLength(), 0);
+    assertEquals(msg.getMapStringInt64Map().getLength(), 0);
+    assertEquals(msg.getMapStringBoolMap().getLength(), 0);
+    assertEquals(msg.getMapStringDoubleMap().getLength(), 0);
+    assertEquals(msg.getMapStringEnumMap().getLength(), 0);
+    assertEquals(msg.getMapStringMsgMap().getLength(), 0);
+
+    // Re-create to clear out any internally-cached wrappers, etc.
+    msg = new msgInfo.constructor();
+    var m = msg.getMapStringStringMap();
+    assertEquals(m.has('asdf'), false);
+    assertEquals(m.get('asdf'), undefined);
+    m.set('asdf', 'hello world');
+    assertEquals(m.has('asdf'), true);
+    assertEquals(m.get('asdf'), 'hello world');
+    m.set('jkl;', 'key 2');
+    assertEquals(m.has('jkl;'), true);
+    assertEquals(m.get('jkl;'), 'key 2');
+    assertEquals(m.getLength(), 2);
+    var it = m.entries();
+    assertElementsEquals(it.next().value, ['asdf', 'hello world']);
+    assertElementsEquals(it.next().value, ['jkl;', 'key 2']);
+    assertEquals(it.next().done, true);
+    checkMapEquals(m, [
+        ['asdf', 'hello world'],
+        ['jkl;', 'key 2']
+    ]);
+    m.del('jkl;');
+    assertEquals(m.has('jkl;'), false);
+    assertEquals(m.get('jkl;'), undefined);
+    assertEquals(m.getLength(), 1);
+    it = m.keys();
+    assertEquals(it.next().value, 'asdf');
+    assertEquals(it.next().done, true);
+    it = m.values();
+    assertEquals(it.next().value, 'hello world');
+    assertEquals(it.next().done, true);
+
+    var count = 0;
+    m.forEach(function(value, key, map) {
+      assertEquals(map, m);
+      assertEquals(key, 'asdf');
+      assertEquals(value, 'hello world');
+      count++;
+    });
+    assertEquals(count, 1);
+
+    m.clear();
+    assertEquals(m.getLength(), 0);
+  });
+
+
+  /**
+   * Tests operations on maps with all key and value types.
+   */
+  it('testAllMapTypes' + suffix, function() {
+    var msg = new msgInfo.constructor();
+    fillMapFields(msg);
+    checkMapFields(msg);
+  });
+
+
+  if (msgInfo.deserializeBinary) {
+    /**
+     * Tests serialization and deserialization in binary format.
+     */
+    it('testBinaryFormat' + suffix, function() {
+      if (goog.userAgent.IE && !goog.userAgent.isDocumentModeOrHigher(10)) {
+        // IE8/9 currently doesn't support binary format because they lack
+        // TypedArray.
+        return;
+      }
+
+      // Check that the format is correct.
+      var msg = new msgInfo.constructor();
+      msg.getMapStringStringMap().set('A', 'a');
+      var serialized = msg.serializeBinary();
+      var expectedSerialized = [
+          0x0a, 0x6, // field 1 (map_string_string), delimited, length 6
+          0x0a, 0x1, // field 1 in submessage (key), delimited, length 1
+          0x41,      // ASCII 'A'
+          0x12, 0x1, // field 2 in submessage (value), delimited, length 1
+          0x61       // ASCII 'a'
+      ];
+      assertEquals(serialized.length, expectedSerialized.length);
+      for (var i = 0; i < serialized.length; i++) {
+        assertEquals(serialized[i], expectedSerialized[i]);
+      }
+
+      // Check that all map fields successfully round-trip.
+      msg = new msgInfo.constructor();
+      fillMapFields(msg);
+      serialized = msg.serializeBinary();
+      var decoded = msgInfo.deserializeBinary(serialized);
+      checkMapFields(decoded);
+    });
+  }
+
+  /**
+   * Exercises the lazy map<->underlying array sync.
+   */
+  it('testLazyMapSync' + suffix, function() {
+    // Start with a JSPB array containing a few map entries.
+    var entries = [
+        ['a', 'entry 1'],
+        ['c', 'entry 2'],
+        ['b', 'entry 3']
+    ];
+    var msg = new msgInfo.constructor([entries]);
+    assertEquals(entries.length, 3);
+    assertEquals(entries[0][0], 'a');
+    assertEquals(entries[1][0], 'c');
+    assertEquals(entries[2][0], 'b');
+    msg.getMapStringStringMap().del('a');
+    assertEquals(entries.length, 3);  // not yet sync'd
+    msg.toArray();                // force a sync
+    assertEquals(entries.length, 2);
+    assertEquals(entries[0][0], 'b'); // now in sorted order
+    assertEquals(entries[1][0], 'c');
+
+    var a = msg.toArray();
+    assertEquals(a[0], entries);  // retains original reference
+  });
+}
+
+describe('mapsTest', function() {
+  makeTests({
+    constructor: proto.jspb.test.TestMapFields,
+    deserializeBinary: proto.jspb.test.TestMapFields.deserializeBinary
+  }, proto.jspb.test.MapValueMessage, "_Binary");
+  makeTests({
+    constructor: proto.jspb.test.TestMapFieldsNoBinary,
+    deserializeBinary: null
+  }, proto.jspb.test.MapValueMessageNoBinary, "_NoBinary");
+});
diff --git a/js/compatibility_tests/v3.1.0/message_test.js b/js/compatibility_tests/v3.1.0/message_test.js
new file mode 100644
index 00000000..b46e50d3
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/message_test.js
@@ -0,0 +1,1037 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Test suite is written using Jasmine -- see http://jasmine.github.io/
+
+goog.setTestOnly();
+
+goog.require('goog.json');
+goog.require('goog.testing.asserts');
+goog.require('goog.userAgent');
+
+// CommonJS-LoadFromFile: google-protobuf jspb
+goog.require('jspb.Message');
+
+// CommonJS-LoadFromFile: test5_pb proto.jspb.exttest.beta
+goog.require('proto.jspb.exttest.beta.floatingStrField');
+
+// CommonJS-LoadFromFile: test3_pb proto.jspb.exttest
+goog.require('proto.jspb.exttest.floatingMsgField');
+
+// CommonJS-LoadFromFile: test4_pb proto.jspb.exttest
+goog.require('proto.jspb.exttest.floatingMsgFieldTwo');
+
+// CommonJS-LoadFromFile: test_pb proto.jspb.test
+goog.require('proto.jspb.test.CloneExtension');
+goog.require('proto.jspb.test.Complex');
+goog.require('proto.jspb.test.DefaultValues');
+goog.require('proto.jspb.test.Empty');
+goog.require('proto.jspb.test.EnumContainer');
+goog.require('proto.jspb.test.floatingMsgField');
+goog.require('proto.jspb.test.FloatingPointFields');
+goog.require('proto.jspb.test.floatingStrField');
+goog.require('proto.jspb.test.HasExtensions');
+goog.require('proto.jspb.test.IndirectExtension');
+goog.require('proto.jspb.test.IsExtension');
+goog.require('proto.jspb.test.OptionalFields');
+goog.require('proto.jspb.test.OuterEnum');
+goog.require('proto.jspb.test.OuterMessage.Complex');
+goog.require('proto.jspb.test.Simple1');
+goog.require('proto.jspb.test.Simple2');
+goog.require('proto.jspb.test.SpecialCases');
+goog.require('proto.jspb.test.TestClone');
+goog.require('proto.jspb.test.TestEndsWithBytes');
+goog.require('proto.jspb.test.TestGroup');
+goog.require('proto.jspb.test.TestGroup1');
+goog.require('proto.jspb.test.TestMessageWithOneof');
+goog.require('proto.jspb.test.TestReservedNames');
+goog.require('proto.jspb.test.TestReservedNamesExtension');
+
+// CommonJS-LoadFromFile: test2_pb proto.jspb.test
+goog.require('proto.jspb.test.ExtensionMessage');
+goog.require('proto.jspb.test.TestExtensionsMessage');
+
+
+
+
+describe('Message test suite', function() {
+  it('testEmptyProto', function() {
+    var empty1 = new proto.jspb.test.Empty([]);
+    var empty2 = new proto.jspb.test.Empty([]);
+    assertObjectEquals({}, empty1.toObject());
+    assertObjectEquals('Message should not be corrupted:', empty2, empty1);
+  });
+
+  it('testTopLevelEnum', function() {
+    var response = new proto.jspb.test.EnumContainer([]);
+    response.setOuterEnum(proto.jspb.test.OuterEnum.FOO);
+    assertEquals(proto.jspb.test.OuterEnum.FOO, response.getOuterEnum());
+  });
+
+  it('testByteStrings', function() {
+    var data = new proto.jspb.test.DefaultValues([]);
+    data.setBytesField('some_bytes');
+    assertEquals('some_bytes', data.getBytesField());
+  });
+
+  it('testComplexConversion', function() {
+    var data1 = ['a',,, [, 11], [[, 22], [, 33]],, ['s1', 's2'],, 1];
+    var data2 = ['a',,, [, 11], [[, 22], [, 33]],, ['s1', 's2'],, 1];
+    var foo = new proto.jspb.test.Complex(data1);
+    var bar = new proto.jspb.test.Complex(data2);
+    var result = foo.toObject();
+    assertObjectEquals({
+      aString: 'a',
+      anOutOfOrderBool: 1,
+      aNestedMessage: {
+        anInt: 11
+      },
+      aRepeatedMessageList: [{anInt: 22}, {anInt: 33}],
+      aRepeatedStringList: ['s1', 's2']
+    }, result);
+
+    // Now test with the jspb instances included.
+    result = foo.toObject(true /* opt_includeInstance */);
+    assertObjectEquals({
+      aString: 'a',
+      anOutOfOrderBool: 1,
+      aNestedMessage: {
+        anInt: 11,
+        $jspbMessageInstance: foo.getANestedMessage()
+      },
+      aRepeatedMessageList: [
+        {anInt: 22, $jspbMessageInstance: foo.getARepeatedMessageList()[0]},
+        {anInt: 33, $jspbMessageInstance: foo.getARepeatedMessageList()[1]}
+      ],
+      aRepeatedStringList: ['s1', 's2'],
+      $jspbMessageInstance: foo
+    }, result);
+
+  });
+
+  it('testMissingFields', function() {
+    var foo = new proto.jspb.test.Complex([
+        undefined, undefined, undefined, [],
+        undefined, undefined, undefined, undefined]);
+    var bar = new proto.jspb.test.Complex([
+        undefined, undefined, undefined, [],
+        undefined, undefined, undefined, undefined]);
+    var result = foo.toObject();
+    assertObjectEquals({
+      aString: undefined,
+      anOutOfOrderBool: undefined,
+      aNestedMessage: {
+        anInt: undefined
+      },
+      // Note: JsPb converts undefined repeated fields to empty arrays.
+      aRepeatedMessageList: [],
+      aRepeatedStringList: []
+    }, result);
+
+  });
+
+  it('testNestedComplexMessage', function() {
+    // Instantiate the message and set a unique field, just to ensure that we
+    // are not getting jspb.test.Complex instead.
+    var msg = new proto.jspb.test.OuterMessage.Complex();
+    msg.setInnerComplexField(5);
+  });
+
+  it('testSpecialCases', function() {
+    // Note: Some property names are reserved in JavaScript.
+    // These names are converted to the Js property named pb_<reserved_name>.
+    var special =
+        new proto.jspb.test.SpecialCases(['normal', 'default', 'function',
+        'var']);
+    var result = special.toObject();
+    assertObjectEquals({
+      normal: 'normal',
+      pb_default: 'default',
+      pb_function: 'function',
+      pb_var: 'var'
+    }, result);
+  });
+
+  it('testDefaultValues', function() {
+    var defaultString = "default<>\'\"abc";
+    var response = new proto.jspb.test.DefaultValues();
+
+    // Test toObject
+    var expectedObject = {
+      stringField: defaultString,
+      boolField: true,
+      intField: 11,
+      enumField: 13,
+      emptyField: '',
+      bytesField: 'bW9v'
+    };
+    assertObjectEquals(expectedObject, response.toObject());
+
+
+    // Test getters
+    response = new proto.jspb.test.DefaultValues();
+    assertEquals(defaultString, response.getStringField());
+    assertEquals(true, response.getBoolField());
+    assertEquals(11, response.getIntField());
+    assertEquals(13, response.getEnumField());
+    assertEquals('', response.getEmptyField());
+    assertEquals('bW9v', response.getBytesField());
+
+    function makeDefault(values) {
+      return new proto.jspb.test.DefaultValues(values);
+    }
+
+    // Test with undefined values,
+    // Use push to workaround IE treating undefined array elements as holes.
+    response = makeDefault([undefined, undefined, undefined, undefined]);
+    assertEquals(defaultString, response.getStringField());
+    assertEquals(true, response.getBoolField());
+    assertEquals(11, response.getIntField());
+    assertEquals(13, response.getEnumField());
+    assertFalse(response.hasStringField());
+    assertFalse(response.hasBoolField());
+    assertFalse(response.hasIntField());
+    assertFalse(response.hasEnumField());
+
+    // Test with null values, as would be returned by a JSON serializer.
+    response = makeDefault([null, null, null, null]);
+    assertEquals(defaultString, response.getStringField());
+    assertEquals(true, response.getBoolField());
+    assertEquals(11, response.getIntField());
+    assertEquals(13, response.getEnumField());
+    assertFalse(response.hasStringField());
+    assertFalse(response.hasBoolField());
+    assertFalse(response.hasIntField());
+    assertFalse(response.hasEnumField());
+
+    // Test with false-like values.
+    response = makeDefault(['', false, 0, 0]);
+    assertEquals('', response.getStringField());
+    assertEquals(false, response.getBoolField());
+    assertEquals(true, response.getIntField() == 0);
+    assertEquals(true, response.getEnumField() == 0);
+    assertTrue(response.hasStringField());
+    assertTrue(response.hasBoolField());
+    assertTrue(response.hasIntField());
+    assertTrue(response.hasEnumField());
+
+    // Test that clearing the values reverts them to the default state.
+    response = makeDefault(['blah', false, 111, 77]);
+    response.clearStringField(); response.clearBoolField();
+    response.clearIntField(); response.clearEnumField();
+    assertEquals(defaultString, response.getStringField());
+    assertEquals(true, response.getBoolField());
+    assertEquals(11, response.getIntField());
+    assertEquals(13, response.getEnumField());
+    assertFalse(response.hasStringField());
+    assertFalse(response.hasBoolField());
+    assertFalse(response.hasIntField());
+    assertFalse(response.hasEnumField());
+
+    // Test that setFoo(null) clears the values.
+    response = makeDefault(['blah', false, 111, 77]);
+    response.setStringField(null); response.setBoolField(null);
+    response.setIntField(undefined); response.setEnumField(undefined);
+    assertEquals(defaultString, response.getStringField());
+    assertEquals(true, response.getBoolField());
+    assertEquals(11, response.getIntField());
+    assertEquals(13, response.getEnumField());
+    assertFalse(response.hasStringField());
+    assertFalse(response.hasBoolField());
+    assertFalse(response.hasIntField());
+    assertFalse(response.hasEnumField());
+  });
+
+  it('testClearFields', function() {
+    var data = ['str', true, [11], [[22], [33]], ['s1', 's2']];
+    var foo = new proto.jspb.test.OptionalFields(data);
+    foo.clearAString();
+    foo.clearABool();
+    foo.clearANestedMessage();
+    foo.clearARepeatedMessageList();
+    foo.clearARepeatedStringList();
+    assertEquals('', foo.getAString());
+    assertEquals(false, foo.getABool());
+    assertUndefined(foo.getANestedMessage());
+    assertFalse(foo.hasAString());
+    assertFalse(foo.hasABool());
+    assertObjectEquals([], foo.getARepeatedMessageList());
+    assertObjectEquals([], foo.getARepeatedStringList());
+    // NOTE: We want the missing fields in 'expected' to be undefined,
+    // but we actually get a sparse array instead. We could use something
+    // like [1,undefined,2] to avoid this, except that this is still
+    // sparse on IE. No comment...
+    var expected = [,,, [], []];
+    expected[0] = expected[1] = expected[2] = undefined;
+    assertObjectEquals(expected, foo.toArray());
+  });
+
+  it('testDifferenceRawObject', /** @suppress {visibility} */ function() {
+    var p1 = new proto.jspb.test.HasExtensions(['hi', 'diff', {}]);
+    var p2 = new proto.jspb.test.HasExtensions(['hi', 'what',
+                                               {1000: 'unique'}]);
+    var diff = /** @type {proto.jspb.test.HasExtensions} */
+        (jspb.Message.difference(p1, p2));
+    assertEquals('', diff.getStr1());
+    assertEquals('what', diff.getStr2());
+    assertEquals('', diff.getStr3());
+    assertEquals('unique', diff.extensionObject_[1000]);
+  });
+
+  it('testEqualsSimple', function() {
+    var s1 = new proto.jspb.test.Simple1(['hi']);
+    assertTrue(jspb.Message.equals(s1, new proto.jspb.test.Simple1(['hi'])));
+    assertFalse(jspb.Message.equals(s1, new proto.jspb.test.Simple1(['bye'])));
+    var s1b = new proto.jspb.test.Simple1(['hi', ['hello']]);
+    assertTrue(jspb.Message.equals(s1b,
+        new proto.jspb.test.Simple1(['hi', ['hello']])));
+    assertTrue(jspb.Message.equals(s1b,
+        new proto.jspb.test.Simple1(['hi', ['hello', undefined,
+                                            undefined, undefined]])));
+    assertFalse(jspb.Message.equals(s1b,
+        new proto.jspb.test.Simple1(['no', ['hello']])));
+    // Test with messages of different types
+    var s2 = new proto.jspb.test.Simple2(['hi']);
+    assertFalse(jspb.Message.equals(s1, s2));
+  });
+
+  it('testEquals_softComparison', function() {
+    var s1 = new proto.jspb.test.Simple1(['hi', [], null]);
+    assertTrue(jspb.Message.equals(s1,
+        new proto.jspb.test.Simple1(['hi', []])));
+
+    var s1b = new proto.jspb.test.Simple1(['hi', [], true]);
+    assertTrue(jspb.Message.equals(s1b,
+        new proto.jspb.test.Simple1(['hi', [], 1])));
+  });
+
+  it('testEqualsComplex', function() {
+    var data1 = ['a',,, [, 11], [[, 22], [, 33]],, ['s1', 's2'],, 1];
+    var data2 = ['a',,, [, 11], [[, 22], [, 34]],, ['s1', 's2'],, 1];
+    var data3 = ['a',,, [, 11], [[, 22]],, ['s1', 's2'],, 1];
+    var data4 = ['hi'];
+    var c1a = new proto.jspb.test.Complex(data1);
+    var c1b = new proto.jspb.test.Complex(data1);
+    var c2 = new proto.jspb.test.Complex(data2);
+    var c3 = new proto.jspb.test.Complex(data3);
+    var s1 = new proto.jspb.test.Simple1(data4);
+
+    assertTrue(jspb.Message.equals(c1a, c1b));
+    assertFalse(jspb.Message.equals(c1a, c2));
+    assertFalse(jspb.Message.equals(c2, c3));
+    assertFalse(jspb.Message.equals(c1a, s1));
+  });
+
+  it('testEqualsExtensionsConstructed', function() {
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions([]),
+        new proto.jspb.test.HasExtensions([{}])
+    ));
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions(['hi', {100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions(['hi', {100: [{200: 'a'}]}])
+    ));
+    assertFalse(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions(['hi', {100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions(['hi', {100: [{200: 'b'}]}])
+    ));
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions([{100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions([{100: [{200: 'a'}]}])
+    ));
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions([{100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions([,,, {100: [{200: 'a'}]}])
+    ));
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions([,,, {100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions([{100: [{200: 'a'}]}])
+    ));
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions(['hi', {100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions(['hi',,, {100: [{200: 'a'}]}])
+    ));
+    assertTrue(jspb.Message.equals(
+        new proto.jspb.test.HasExtensions(['hi',,, {100: [{200: 'a'}]}]),
+        new proto.jspb.test.HasExtensions(['hi', {100: [{200: 'a'}]}])
+    ));
+  });
+
+  it('testEqualsExtensionsUnconstructed', function() {
+    assertTrue(jspb.Message.compareFields([], [{}]));
+    assertTrue(jspb.Message.compareFields([,,, {}], []));
+    assertTrue(jspb.Message.compareFields([,,, {}], [,, {}]));
+    assertTrue(jspb.Message.compareFields(
+        ['hi', {100: [{200: 'a'}]}], ['hi', {100: [{200: 'a'}]}]));
+    assertFalse(jspb.Message.compareFields(
+        ['hi', {100: [{200: 'a'}]}], ['hi', {100: [{200: 'b'}]}]));
+    assertTrue(jspb.Message.compareFields(
+        [{100: [{200: 'a'}]}], [{100: [{200: 'a'}]}]));
+    assertTrue(jspb.Message.compareFields(
+        [{100: [{200: 'a'}]}], [,,, {100: [{200: 'a'}]}]));
+    assertTrue(jspb.Message.compareFields(
+        [,,, {100: [{200: 'a'}]}], [{100: [{200: 'a'}]}]));
+    assertTrue(jspb.Message.compareFields(
+        ['hi', {100: [{200: 'a'}]}], ['hi',,, {100: [{200: 'a'}]}]));
+    assertTrue(jspb.Message.compareFields(
+        ['hi',,, {100: [{200: 'a'}]}], ['hi', {100: [{200: 'a'}]}]));
+  });
+
+  it('testToMap', function() {
+    var p1 = new proto.jspb.test.Simple1(['k', ['v']]);
+    var p2 = new proto.jspb.test.Simple1(['k1', ['v1', 'v2']]);
+    var soymap = jspb.Message.toMap([p1, p2],
+        proto.jspb.test.Simple1.prototype.getAString,
+        proto.jspb.test.Simple1.prototype.toObject);
+    assertEquals('k', soymap['k'].aString);
+    assertArrayEquals(['v'], soymap['k'].aRepeatedStringList);
+    var protomap = jspb.Message.toMap([p1, p2],
+        proto.jspb.test.Simple1.prototype.getAString);
+    assertEquals('k', protomap['k'].getAString());
+    assertArrayEquals(['v'], protomap['k'].getARepeatedStringList());
+  });
+
+  it('testClone', function() {
+    var supportsUint8Array =
+        !goog.userAgent.IE || goog.userAgent.isVersionOrHigher('10');
+    var original = new proto.jspb.test.TestClone();
+    original.setStr('v1');
+    var simple1 = new proto.jspb.test.Simple1(['x1', ['y1', 'z1']]);
+    var simple2 = new proto.jspb.test.Simple1(['x2', ['y2', 'z2']]);
+    var simple3 = new proto.jspb.test.Simple1(['x3', ['y3', 'z3']]);
+    original.setSimple1(simple1);
+    original.setSimple2List([simple2, simple3]);
+    var bytes1 = supportsUint8Array ? new Uint8Array([1, 2, 3]) : '123';
+    original.setBytesField(bytes1);
+    var extension = new proto.jspb.test.CloneExtension();
+    extension.setExt('e1');
+    original.setExtension(proto.jspb.test.IsExtension.extField, extension);
+    var clone = original.clone();
+    assertArrayEquals(['v1',, ['x1', ['y1', 'z1']],,
+      [['x2', ['y2', 'z2']], ['x3', ['y3', 'z3']]], bytes1,, { 100: [, 'e1'] }],
+        clone.toArray());
+    clone.setStr('v2');
+    var simple4 = new proto.jspb.test.Simple1(['a1', ['b1', 'c1']]);
+    var simple5 = new proto.jspb.test.Simple1(['a2', ['b2', 'c2']]);
+    var simple6 = new proto.jspb.test.Simple1(['a3', ['b3', 'c3']]);
+    clone.setSimple1(simple4);
+    clone.setSimple2List([simple5, simple6]);
+    if (supportsUint8Array) {
+      clone.getBytesField()[0] = 4;
+      assertObjectEquals(bytes1, original.getBytesField());
+    }
+    var bytes2 = supportsUint8Array ? new Uint8Array([4, 5, 6]) : '456';
+    clone.setBytesField(bytes2);
+    var newExtension = new proto.jspb.test.CloneExtension();
+    newExtension.setExt('e2');
+    clone.setExtension(proto.jspb.test.CloneExtension.extField, newExtension);
+    assertArrayEquals(['v2',, ['a1', ['b1', 'c1']],,
+      [['a2', ['b2', 'c2']], ['a3', ['b3', 'c3']]], bytes2,, { 100: [, 'e2'] }],
+        clone.toArray());
+    assertArrayEquals(['v1',, ['x1', ['y1', 'z1']],,
+      [['x2', ['y2', 'z2']], ['x3', ['y3', 'z3']]], bytes1,, { 100: [, 'e1'] }],
+        original.toArray());
+  });
+
+  it('testCopyInto', function() {
+    var supportsUint8Array =
+        !goog.userAgent.IE || goog.userAgent.isVersionOrHigher('10');
+    var original = new proto.jspb.test.TestClone();
+    original.setStr('v1');
+    var dest = new proto.jspb.test.TestClone();
+    dest.setStr('override');
+    var simple1 = new proto.jspb.test.Simple1(['x1', ['y1', 'z1']]);
+    var simple2 = new proto.jspb.test.Simple1(['x2', ['y2', 'z2']]);
+    var simple3 = new proto.jspb.test.Simple1(['x3', ['y3', 'z3']]);
+    var destSimple1 = new proto.jspb.test.Simple1(['ox1', ['oy1', 'oz1']]);
+    var destSimple2 = new proto.jspb.test.Simple1(['ox2', ['oy2', 'oz2']]);
+    var destSimple3 = new proto.jspb.test.Simple1(['ox3', ['oy3', 'oz3']]);
+    original.setSimple1(simple1);
+    original.setSimple2List([simple2, simple3]);
+    dest.setSimple1(destSimple1);
+    dest.setSimple2List([destSimple2, destSimple3]);
+    var bytes1 = supportsUint8Array ? new Uint8Array([1, 2, 3]) : '123';
+    var bytes2 = supportsUint8Array ? new Uint8Array([4, 5, 6]) : '456';
+    original.setBytesField(bytes1);
+    dest.setBytesField(bytes2);
+    var extension = new proto.jspb.test.CloneExtension();
+    extension.setExt('e1');
+    original.setExtension(proto.jspb.test.CloneExtension.extField, extension);
+
+    jspb.Message.copyInto(original, dest);
+    assertArrayEquals(original.toArray(), dest.toArray());
+    assertEquals('x1', dest.getSimple1().getAString());
+    assertEquals('e1',
+        dest.getExtension(proto.jspb.test.CloneExtension.extField).getExt());
+    dest.getSimple1().setAString('new value');
+    assertNotEquals(dest.getSimple1().getAString(),
+        original.getSimple1().getAString());
+    if (supportsUint8Array) {
+      dest.getBytesField()[0] = 7;
+      assertObjectEquals(bytes1, original.getBytesField());
+      assertObjectEquals(new Uint8Array([7, 2, 3]), dest.getBytesField());
+    } else {
+      dest.setBytesField('789');
+      assertObjectEquals(bytes1, original.getBytesField());
+      assertObjectEquals('789', dest.getBytesField());
+    }
+    dest.getExtension(proto.jspb.test.CloneExtension.extField).
+        setExt('new value');
+    assertNotEquals(
+        dest.getExtension(proto.jspb.test.CloneExtension.extField).getExt(),
+        original.getExtension(
+            proto.jspb.test.CloneExtension.extField).getExt());
+  });
+
+  it('testCopyInto_notSameType', function() {
+    var a = new proto.jspb.test.TestClone();
+    var b = new proto.jspb.test.Simple1(['str', ['s1', 's2']]);
+
+    var e = assertThrows(function() {
+      jspb.Message.copyInto(a, b);
+    });
+    assertContains('should have the same type', e.message);
+  });
+
+  it('testExtensions', function() {
+    var extension1 = new proto.jspb.test.IsExtension(['ext1field']);
+    var extension2 = new proto.jspb.test.Simple1(['str', ['s1', 's2']]);
+    var extendable = new proto.jspb.test.HasExtensions(['v1', 'v2', 'v3']);
+    extendable.setExtension(proto.jspb.test.IsExtension.extField, extension1);
+    extendable.setExtension(proto.jspb.test.IndirectExtension.simple,
+                            extension2);
+    extendable.setExtension(proto.jspb.test.IndirectExtension.str, 'xyzzy');
+    extendable.setExtension(proto.jspb.test.IndirectExtension.repeatedStrList,
+        ['a', 'b']);
+    var s1 = new proto.jspb.test.Simple1(['foo', ['s1', 's2']]);
+    var s2 = new proto.jspb.test.Simple1(['bar', ['t1', 't2']]);
+    extendable.setExtension(
+        proto.jspb.test.IndirectExtension.repeatedSimpleList,
+        [s1, s2]);
+    assertObjectEquals(extension1,
+        extendable.getExtension(proto.jspb.test.IsExtension.extField));
+    assertObjectEquals(extension2,
+        extendable.getExtension(proto.jspb.test.IndirectExtension.simple));
+    assertObjectEquals('xyzzy',
+        extendable.getExtension(proto.jspb.test.IndirectExtension.str));
+    assertObjectEquals(['a', 'b'], extendable.getExtension(
+        proto.jspb.test.IndirectExtension.repeatedStrList));
+    assertObjectEquals([s1, s2], extendable.getExtension(
+        proto.jspb.test.IndirectExtension.repeatedSimpleList));
+    // Not supported yet, but it should work...
+    extendable.setExtension(proto.jspb.test.IndirectExtension.simple, null);
+    assertNull(
+        extendable.getExtension(proto.jspb.test.IndirectExtension.simple));
+    extendable.setExtension(proto.jspb.test.IndirectExtension.str, null);
+    assertNull(extendable.getExtension(proto.jspb.test.IndirectExtension.str));
+
+
+    // Extension fields with jspb.ignore = true are ignored.
+    assertUndefined(proto.jspb.test.IndirectExtension['ignored']);
+    assertUndefined(proto.jspb.test.HasExtensions['ignoredFloating']);
+  });
+
+  it('testFloatingExtensions', function() {
+    // From an autogenerated container.
+    var extendable = new proto.jspb.test.HasExtensions(['v1', 'v2', 'v3']);
+    var extension = new proto.jspb.test.Simple1(['foo', ['s1', 's2']]);
+    extendable.setExtension(proto.jspb.test.simple1, extension);
+    assertObjectEquals(extension,
+        extendable.getExtension(proto.jspb.test.simple1));
+
+    // From _lib mode.
+    extension = new proto.jspb.test.ExtensionMessage(['s1']);
+    extendable = new proto.jspb.test.TestExtensionsMessage([16]);
+    extendable.setExtension(proto.jspb.test.floatingMsgField, extension);
+    extendable.setExtension(proto.jspb.test.floatingStrField, 's2');
+    assertObjectEquals(extension,
+        extendable.getExtension(proto.jspb.test.floatingMsgField));
+    assertObjectEquals('s2',
+        extendable.getExtension(proto.jspb.test.floatingStrField));
+    assertNotUndefined(proto.jspb.exttest.floatingMsgField);
+    assertNotUndefined(proto.jspb.exttest.floatingMsgFieldTwo);
+    assertNotUndefined(proto.jspb.exttest.beta.floatingStrField);
+  });
+
+  it('testToObject_extendedObject', function() {
+    var extension1 = new proto.jspb.test.IsExtension(['ext1field']);
+    var extension2 = new proto.jspb.test.Simple1(['str', ['s1', 's2'], true]);
+    var extendable = new proto.jspb.test.HasExtensions(['v1', 'v2', 'v3']);
+    extendable.setExtension(proto.jspb.test.IsExtension.extField, extension1);
+    extendable.setExtension(proto.jspb.test.IndirectExtension.simple,
+                            extension2);
+    extendable.setExtension(proto.jspb.test.IndirectExtension.str, 'xyzzy');
+    extendable.setExtension(proto.jspb.test.IndirectExtension.repeatedStrList,
+        ['a', 'b']);
+    var s1 = new proto.jspb.test.Simple1(['foo', ['s1', 's2'], true]);
+    var s2 = new proto.jspb.test.Simple1(['bar', ['t1', 't2'], false]);
+    extendable.setExtension(
+        proto.jspb.test.IndirectExtension.repeatedSimpleList,
+        [s1, s2]);
+    assertObjectEquals({
+      str1: 'v1', str2: 'v2', str3: 'v3',
+      extField: { ext1: 'ext1field' },
+      simple: {
+        aString: 'str', aRepeatedStringList: ['s1', 's2'], aBoolean: true
+      },
+      str: 'xyzzy',
+      repeatedStrList: ['a', 'b'],
+      repeatedSimpleList: [
+        { aString: 'foo', aRepeatedStringList: ['s1', 's2'], aBoolean: true},
+        { aString: 'bar', aRepeatedStringList: ['t1', 't2'], aBoolean: false}
+      ]
+    }, extendable.toObject());
+
+    // Now, with instances included.
+    assertObjectEquals({
+      str1: 'v1', str2: 'v2', str3: 'v3',
+      extField: {
+        ext1: 'ext1field',
+        $jspbMessageInstance:
+            extendable.getExtension(proto.jspb.test.IsExtension.extField)
+      },
+      simple: {
+        aString: 'str',
+        aRepeatedStringList: ['s1', 's2'],
+        aBoolean: true,
+        $jspbMessageInstance:
+            extendable.getExtension(proto.jspb.test.IndirectExtension.simple)
+      },
+      str: 'xyzzy',
+      repeatedStrList: ['a', 'b'],
+      repeatedSimpleList: [{
+        aString: 'foo',
+        aRepeatedStringList: ['s1', 's2'],
+        aBoolean: true,
+        $jspbMessageInstance: s1
+      }, {
+        aString: 'bar',
+        aRepeatedStringList: ['t1', 't2'],
+        aBoolean: false,
+        $jspbMessageInstance: s2
+      }],
+      $jspbMessageInstance: extendable
+    }, extendable.toObject(true /* opt_includeInstance */));
+  });
+
+  it('testInitialization_emptyArray', function() {
+    var msg = new proto.jspb.test.HasExtensions([]);
+    if (jspb.Message.MINIMIZE_MEMORY_ALLOCATIONS) {
+      assertArrayEquals([], msg.toArray());
+    } else {
+      // Extension object is created past all regular fields.
+      assertArrayEquals([,,, {}], msg.toArray());
+    }
+  });
+
+  it('testInitialization_justExtensionObject', function() {
+    var msg = new proto.jspb.test.Empty([{1: 'hi'}]);
+    // The extensionObject is not moved from its original location.
+    assertArrayEquals([{1: 'hi'}], msg.toArray());
+  });
+
+  it('testInitialization_incompleteList', function() {
+    var msg = new proto.jspb.test.Empty([1, {4: 'hi'}]);
+    // The extensionObject is not moved from its original location.
+    assertArrayEquals([1, {4: 'hi'}], msg.toArray());
+  });
+
+  it('testInitialization_forwardCompatible', function() {
+    var msg = new proto.jspb.test.Empty([1, 2, 3, {1: 'hi'}]);
+    assertArrayEquals([1, 2, 3, {1: 'hi'}], msg.toArray());
+  });
+
+  it('testExtendedMessageEnsureObject',
+     /** @suppress {visibility} */ function() {
+       var data =
+           new proto.jspb.test.HasExtensions(['str1', {'a_key': 'an_object'}]);
+       assertEquals('an_object', data.extensionObject_['a_key']);
+     });
+
+  it('testToObject_hasExtensionField', function() {
+    var data = new proto.jspb.test.HasExtensions(['str1', {100: ['ext1']}]);
+    var obj = data.toObject();
+    assertEquals('str1', obj.str1);
+    assertEquals('ext1', obj.extField.ext1);
+  });
+
+  it('testGetExtension', function() {
+    var data = new proto.jspb.test.HasExtensions(['str1', {100: ['ext1']}]);
+    assertEquals('str1', data.getStr1());
+    var extension = data.getExtension(proto.jspb.test.IsExtension.extField);
+    assertNotNull(extension);
+    assertEquals('ext1', extension.getExt1());
+  });
+
+  it('testSetExtension', function() {
+    var data = new proto.jspb.test.HasExtensions();
+    var extensionMessage = new proto.jspb.test.IsExtension(['is_extension']);
+    data.setExtension(proto.jspb.test.IsExtension.extField, extensionMessage);
+    var obj = data.toObject();
+    assertNotNull(
+        data.getExtension(proto.jspb.test.IsExtension.extField));
+    assertEquals('is_extension', obj.extField.ext1);
+  });
+
+  /**
+   * Note that group is long deprecated, we only support it because JsPb has
+   * a goal of being able to generate JS classes for all proto descriptors.
+   */
+  it('testGroups', function() {
+    var group = new proto.jspb.test.TestGroup();
+    var someGroup = new proto.jspb.test.TestGroup.RepeatedGroup();
+    someGroup.setId('g1');
+    someGroup.setSomeBoolList([true, false]);
+    group.setRepeatedGroupList([someGroup]);
+    var groups = group.getRepeatedGroupList();
+    assertEquals('g1', groups[0].getId());
+    assertObjectEquals([true, false], groups[0].getSomeBoolList());
+    assertObjectEquals({id: 'g1', someBoolList: [true, false]},
+        groups[0].toObject());
+    assertObjectEquals({
+      repeatedGroupList: [{id: 'g1', someBoolList: [true, false]}],
+      requiredGroup: {id: undefined},
+      optionalGroup: undefined,
+      requiredSimple: {aRepeatedStringList: [], aString: undefined},
+      optionalSimple: undefined,
+      id: undefined
+    }, group.toObject());
+    var group1 = new proto.jspb.test.TestGroup1();
+    group1.setGroup(someGroup);
+    assertEquals(someGroup, group1.getGroup());
+  });
+
+  it('testNonExtensionFieldsAfterExtensionRange', function() {
+    var data = [{'1': 'a_string'}];
+    var message = new proto.jspb.test.Complex(data);
+    assertArrayEquals([], message.getARepeatedStringList());
+  });
+
+  it('testReservedGetterNames', function() {
+    var message = new proto.jspb.test.TestReservedNames();
+    message.setExtension$(11);
+    message.setExtension(proto.jspb.test.TestReservedNamesExtension.foo, 12);
+    assertEquals(11, message.getExtension$());
+    assertEquals(12, message.getExtension(
+        proto.jspb.test.TestReservedNamesExtension.foo));
+    assertObjectEquals({extension: 11, foo: 12}, message.toObject());
+  });
+
+  it('testInitializeMessageWithUnsetOneof', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof([]);
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.
+            PARTIAL_ONEOF_NOT_SET,
+        message.getPartialOneofCase());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.RecursiveOneofCase.
+            RECURSIVE_ONEOF_NOT_SET,
+        message.getRecursiveOneofCase());
+  });
+
+  it('testInitializeMessageWithSingleValueSetInOneof', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof([,, 'x']);
+
+    assertEquals('x', message.getPone());
+    assertEquals('', message.getPthree());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.PONE,
+        message.getPartialOneofCase());
+  });
+
+  it('testKeepsLastWireValueSetInUnion_multipleValues', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof([,, 'x',, 'y']);
+
+    assertEquals('', message.getPone());
+    assertEquals('y', message.getPthree());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.PTHREE,
+        message.getPartialOneofCase());
+  });
+
+  it('testSettingOneofFieldClearsOthers', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    assertEquals('', message.getPone());
+    assertEquals('', message.getPthree());
+    assertFalse(message.hasPone());
+    assertFalse(message.hasPthree());
+
+    message.setPone('hi');
+    assertEquals('hi', message.getPone());
+    assertEquals('', message.getPthree());
+    assertTrue(message.hasPone());
+    assertFalse(message.hasPthree());
+
+    message.setPthree('bye');
+    assertEquals('', message.getPone());
+    assertEquals('bye', message.getPthree());
+    assertFalse(message.hasPone());
+    assertTrue(message.hasPthree());
+  });
+
+  it('testSettingOneofFieldDoesNotClearFieldsFromOtherUnions', function() {
+    var other = new proto.jspb.test.TestMessageWithOneof;
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    assertEquals('', message.getPone());
+    assertEquals('', message.getPthree());
+    assertUndefined(message.getRone());
+    assertFalse(message.hasPone());
+    assertFalse(message.hasPthree());
+
+    message.setPone('hi');
+    message.setRone(other);
+    assertEquals('hi', message.getPone());
+    assertEquals('', message.getPthree());
+    assertEquals(other, message.getRone());
+    assertTrue(message.hasPone());
+    assertFalse(message.hasPthree());
+
+    message.setPthree('bye');
+    assertEquals('', message.getPone());
+    assertEquals('bye', message.getPthree());
+    assertEquals(other, message.getRone());
+    assertFalse(message.hasPone());
+    assertTrue(message.hasPthree());
+  });
+
+  it('testUnsetsOneofCaseWhenFieldIsCleared', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.
+            PARTIAL_ONEOF_NOT_SET,
+        message.getPartialOneofCase());
+
+    message.setPone('hi');
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.PONE,
+        message.getPartialOneofCase());
+
+    message.clearPone();
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.
+            PARTIAL_ONEOF_NOT_SET,
+        message.getPartialOneofCase());
+  });
+
+  it('testMessageWithDefaultOneofValues', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    assertEquals(1234, message.getAone());
+    assertEquals(0, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase
+            .DEFAULT_ONEOF_A_NOT_SET,
+        message.getDefaultOneofACase());
+
+    message.setAone(567);
+    assertEquals(567, message.getAone());
+    assertEquals(0, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase.AONE,
+        message.getDefaultOneofACase());
+
+    message.setAtwo(890);
+    assertEquals(1234, message.getAone());
+    assertEquals(890, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase.ATWO,
+        message.getDefaultOneofACase());
+
+    message.clearAtwo();
+    assertEquals(1234, message.getAone());
+    assertEquals(0, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase
+            .DEFAULT_ONEOF_A_NOT_SET,
+        message.getDefaultOneofACase());
+  });
+
+  it('testMessageWithDefaultOneofValues_defaultNotOnFirstField', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    assertEquals(0, message.getBone());
+    assertEquals(1234, message.getBtwo());
+    assertFalse(message.hasBone());
+    assertFalse(message.hasBtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase
+            .DEFAULT_ONEOF_B_NOT_SET,
+        message.getDefaultOneofBCase());
+
+    message.setBone(2);
+    assertEquals(2, message.getBone());
+    assertEquals(1234, message.getBtwo());
+    assertTrue(message.hasBone());
+    assertFalse(message.hasBtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase.BONE,
+        message.getDefaultOneofBCase());
+
+    message.setBtwo(3);
+    assertEquals(0, message.getBone());
+    assertFalse(message.hasBone());
+    assertTrue(message.hasBtwo());
+    assertEquals(3, message.getBtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase.BTWO,
+        message.getDefaultOneofBCase());
+
+    message.clearBtwo();
+    assertEquals(0, message.getBone());
+    assertFalse(message.hasBone());
+    assertFalse(message.hasBtwo());
+    assertEquals(1234, message.getBtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase
+            .DEFAULT_ONEOF_B_NOT_SET,
+        message.getDefaultOneofBCase());
+  });
+
+  it('testInitializeMessageWithOneofDefaults', function() {
+    var message =
+        new proto.jspb.test.TestMessageWithOneof(new Array(9).concat(567));
+    assertEquals(567, message.getAone());
+    assertEquals(0, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase.AONE,
+        message.getDefaultOneofACase());
+
+    message =
+        new proto.jspb.test.TestMessageWithOneof(new Array(10).concat(890));
+    assertEquals(1234, message.getAone());
+    assertEquals(890, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase.ATWO,
+        message.getDefaultOneofACase());
+
+    message =
+        new proto.jspb.test.TestMessageWithOneof(new Array(9).concat(567, 890));
+    assertEquals(1234, message.getAone());
+    assertEquals(890, message.getAtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.DefaultOneofACase.ATWO,
+        message.getDefaultOneofACase());
+  });
+
+  it('testInitializeMessageWithOneofDefaults_defaultNotSetOnFirstField',
+      function() {
+        var message;
+
+        message =
+            new proto.jspb.test.TestMessageWithOneof(new Array(11).concat(567));
+        assertEquals(567, message.getBone());
+        assertEquals(1234, message.getBtwo());
+        assertEquals(
+            proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase.BONE,
+            message.getDefaultOneofBCase());
+
+        message =
+            new proto.jspb.test.TestMessageWithOneof(new Array(12).concat(890));
+        assertEquals(0, message.getBone());
+        assertEquals(890, message.getBtwo());
+        assertEquals(
+            proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase.BTWO,
+            message.getDefaultOneofBCase());
+
+        message = new proto.jspb.test.TestMessageWithOneof(
+            new Array(11).concat(567, 890));
+        assertEquals(0, message.getBone());
+        assertEquals(890, message.getBtwo());
+        assertEquals(
+            proto.jspb.test.TestMessageWithOneof.DefaultOneofBCase.BTWO,
+            message.getDefaultOneofBCase());
+      });
+
+  it('testOneofContainingAnotherMessage', function() {
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.RecursiveOneofCase.
+            RECURSIVE_ONEOF_NOT_SET,
+        message.getRecursiveOneofCase());
+
+    var other = new proto.jspb.test.TestMessageWithOneof;
+    message.setRone(other);
+    assertEquals(other, message.getRone());
+    assertEquals('', message.getRtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.RecursiveOneofCase.RONE,
+        message.getRecursiveOneofCase());
+
+    message.setRtwo('hi');
+    assertUndefined(message.getRone());
+    assertEquals('hi', message.getRtwo());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.RecursiveOneofCase.RTWO,
+        message.getRecursiveOneofCase());
+  });
+
+  it('testQueryingOneofCaseEnsuresOnlyOneFieldIsSetInUnderlyingArray',
+     function() {
+    var message = new proto.jspb.test.TestMessageWithOneof;
+    message.setPone('x');
+    assertEquals('x', message.getPone());
+    assertEquals('', message.getPthree());
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.PONE,
+        message.getPartialOneofCase());
+
+    var array = message.toArray();
+    assertEquals('x', array[2]);
+    assertUndefined(array[4]);
+    array[4] = 'y';
+
+    assertEquals(
+        proto.jspb.test.TestMessageWithOneof.PartialOneofCase.PTHREE,
+        message.getPartialOneofCase());
+    assertUndefined(array[2]);
+    assertEquals('y', array[4]);
+  });
+
+  it('testFloatingPointFieldsSupportNan', function() {
+    var assertNan = function(x) {
+      assertTrue('Expected ' + x + ' (' + goog.typeOf(x) + ') to be NaN.',
+          goog.isNumber(x) && isNaN(x));
+    };
+
+    var message = new proto.jspb.test.FloatingPointFields([
+      'NaN', 'NaN', ['NaN', 'NaN'], 'NaN',
+      'NaN', 'NaN', ['NaN', 'NaN'], 'NaN'
+    ]);
+    assertNan(message.getOptionalFloatField());
+    assertNan(message.getRequiredFloatField());
+    assertNan(message.getRepeatedFloatFieldList()[0]);
+    assertNan(message.getRepeatedFloatFieldList()[1]);
+    assertNan(message.getDefaultFloatField());
+    assertNan(message.getOptionalDoubleField());
+    assertNan(message.getRequiredDoubleField());
+    assertNan(message.getRepeatedDoubleFieldList()[0]);
+    assertNan(message.getRepeatedDoubleFieldList()[1]);
+    assertNan(message.getDefaultDoubleField());
+  });
+
+});
diff --git a/js/compatibility_tests/v3.1.0/proto3_test.js b/js/compatibility_tests/v3.1.0/proto3_test.js
new file mode 100644
index 00000000..3c929eff
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/proto3_test.js
@@ -0,0 +1,329 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+goog.require('goog.crypt.base64');
+goog.require('goog.testing.asserts');
+
+// CommonJS-LoadFromFile: testbinary_pb proto.jspb.test
+goog.require('proto.jspb.test.ForeignMessage');
+
+// CommonJS-LoadFromFile: proto3_test_pb proto.jspb.test
+goog.require('proto.jspb.test.Proto3Enum');
+goog.require('proto.jspb.test.TestProto3');
+
+
+var BYTES = new Uint8Array([1, 2, 8, 9]);
+var BYTES_B64 = goog.crypt.base64.encodeByteArray(BYTES);
+
+
+/**
+ * Helper: compare a bytes field to an expected value
+ * @param {Uint8Array|string} arr
+ * @param {Uint8Array} expected
+ * @return {boolean}
+ */
+function bytesCompare(arr, expected) {
+  if (goog.isString(arr)) {
+    arr = goog.crypt.base64.decodeStringToUint8Array(arr);
+  }
+  if (arr.length != expected.length) {
+    return false;
+  }
+  for (var i = 0; i < arr.length; i++) {
+    if (arr[i] != expected[i]) {
+      return false;
+    }
+  }
+  return true;
+}
+
+
+describe('proto3Test', function() {
+  /**
+   * Test defaults for proto3 message fields.
+   */
+  it('testProto3FieldDefaults', function() {
+    var msg = new proto.jspb.test.TestProto3();
+
+    assertEquals(msg.getOptionalInt32(), 0);
+    assertEquals(msg.getOptionalInt64(), 0);
+    assertEquals(msg.getOptionalUint32(), 0);
+    assertEquals(msg.getOptionalUint64(), 0);
+    assertEquals(msg.getOptionalSint32(), 0);
+    assertEquals(msg.getOptionalSint64(), 0);
+    assertEquals(msg.getOptionalFixed32(), 0);
+    assertEquals(msg.getOptionalFixed64(), 0);
+    assertEquals(msg.getOptionalSfixed32(), 0);
+    assertEquals(msg.getOptionalSfixed64(), 0);
+    assertEquals(msg.getOptionalFloat(), 0);
+    assertEquals(msg.getOptionalDouble(), 0);
+    assertEquals(msg.getOptionalString(), '');
+
+    // TODO(b/26173701): when we change bytes fields default getter to return
+    // Uint8Array, we'll want to switch this assertion to match the u8 case.
+    assertEquals(typeof msg.getOptionalBytes(), 'string');
+    assertEquals(msg.getOptionalBytes_asU8() instanceof Uint8Array, true);
+    assertEquals(typeof msg.getOptionalBytes_asB64(), 'string');
+    assertEquals(msg.getOptionalBytes().length, 0);
+    assertEquals(msg.getOptionalBytes_asU8().length, 0);
+    assertEquals(msg.getOptionalBytes_asB64(), '');
+
+    assertEquals(msg.getOptionalForeignEnum(),
+                 proto.jspb.test.Proto3Enum.PROTO3_FOO);
+    assertEquals(msg.getOptionalForeignMessage(), undefined);
+    assertEquals(msg.getOptionalForeignMessage(), undefined);
+
+    assertEquals(msg.getRepeatedInt32List().length, 0);
+    assertEquals(msg.getRepeatedInt64List().length, 0);
+    assertEquals(msg.getRepeatedUint32List().length, 0);
+    assertEquals(msg.getRepeatedUint64List().length, 0);
+    assertEquals(msg.getRepeatedSint32List().length, 0);
+    assertEquals(msg.getRepeatedSint64List().length, 0);
+    assertEquals(msg.getRepeatedFixed32List().length, 0);
+    assertEquals(msg.getRepeatedFixed64List().length, 0);
+    assertEquals(msg.getRepeatedSfixed32List().length, 0);
+    assertEquals(msg.getRepeatedSfixed64List().length, 0);
+    assertEquals(msg.getRepeatedFloatList().length, 0);
+    assertEquals(msg.getRepeatedDoubleList().length, 0);
+    assertEquals(msg.getRepeatedStringList().length, 0);
+    assertEquals(msg.getRepeatedBytesList().length, 0);
+    assertEquals(msg.getRepeatedForeignEnumList().length, 0);
+    assertEquals(msg.getRepeatedForeignMessageList().length, 0);
+
+  });
+
+
+  /**
+   * Test that all fields can be set and read via a serialization roundtrip.
+   */
+  it('testProto3FieldSetGet', function() {
+    var msg = new proto.jspb.test.TestProto3();
+
+    msg.setOptionalInt32(-42);
+    msg.setOptionalInt64(-0x7fffffff00000000);
+    msg.setOptionalUint32(0x80000000);
+    msg.setOptionalUint64(0xf000000000000000);
+    msg.setOptionalSint32(-100);
+    msg.setOptionalSint64(-0x8000000000000000);
+    msg.setOptionalFixed32(1234);
+    msg.setOptionalFixed64(0x1234567800000000);
+    msg.setOptionalSfixed32(-1234);
+    msg.setOptionalSfixed64(-0x1234567800000000);
+    msg.setOptionalFloat(1.5);
+    msg.setOptionalDouble(-1.5);
+    msg.setOptionalBool(true);
+    msg.setOptionalString('hello world');
+    msg.setOptionalBytes(BYTES);
+    var submsg = new proto.jspb.test.ForeignMessage();
+    submsg.setC(16);
+    msg.setOptionalForeignMessage(submsg);
+    msg.setOptionalForeignEnum(proto.jspb.test.Proto3Enum.PROTO3_BAR);
+
+    msg.setRepeatedInt32List([-42]);
+    msg.setRepeatedInt64List([-0x7fffffff00000000]);
+    msg.setRepeatedUint32List([0x80000000]);
+    msg.setRepeatedUint64List([0xf000000000000000]);
+    msg.setRepeatedSint32List([-100]);
+    msg.setRepeatedSint64List([-0x8000000000000000]);
+    msg.setRepeatedFixed32List([1234]);
+    msg.setRepeatedFixed64List([0x1234567800000000]);
+    msg.setRepeatedSfixed32List([-1234]);
+    msg.setRepeatedSfixed64List([-0x1234567800000000]);
+    msg.setRepeatedFloatList([1.5]);
+    msg.setRepeatedDoubleList([-1.5]);
+    msg.setRepeatedBoolList([true]);
+    msg.setRepeatedStringList(['hello world']);
+    msg.setRepeatedBytesList([BYTES]);
+    submsg = new proto.jspb.test.ForeignMessage();
+    submsg.setC(1000);
+    msg.setRepeatedForeignMessageList([submsg]);
+    msg.setRepeatedForeignEnumList([proto.jspb.test.Proto3Enum.PROTO3_BAR]);
+
+    msg.setOneofString('asdf');
+
+    var serialized = msg.serializeBinary();
+    msg = proto.jspb.test.TestProto3.deserializeBinary(serialized);
+
+    assertEquals(msg.getOptionalInt32(), -42);
+    assertEquals(msg.getOptionalInt64(), -0x7fffffff00000000);
+    assertEquals(msg.getOptionalUint32(), 0x80000000);
+    assertEquals(msg.getOptionalUint64(), 0xf000000000000000);
+    assertEquals(msg.getOptionalSint32(), -100);
+    assertEquals(msg.getOptionalSint64(), -0x8000000000000000);
+    assertEquals(msg.getOptionalFixed32(), 1234);
+    assertEquals(msg.getOptionalFixed64(), 0x1234567800000000);
+    assertEquals(msg.getOptionalSfixed32(), -1234);
+    assertEquals(msg.getOptionalSfixed64(), -0x1234567800000000);
+    assertEquals(msg.getOptionalFloat(), 1.5);
+    assertEquals(msg.getOptionalDouble(), -1.5);
+    assertEquals(msg.getOptionalBool(), true);
+    assertEquals(msg.getOptionalString(), 'hello world');
+    assertEquals(true, bytesCompare(msg.getOptionalBytes(), BYTES));
+    assertEquals(msg.getOptionalForeignMessage().getC(), 16);
+    assertEquals(msg.getOptionalForeignEnum(),
+        proto.jspb.test.Proto3Enum.PROTO3_BAR);
+
+    assertElementsEquals(msg.getRepeatedInt32List(), [-42]);
+    assertElementsEquals(msg.getRepeatedInt64List(), [-0x7fffffff00000000]);
+    assertElementsEquals(msg.getRepeatedUint32List(), [0x80000000]);
+    assertElementsEquals(msg.getRepeatedUint64List(), [0xf000000000000000]);
+    assertElementsEquals(msg.getRepeatedSint32List(), [-100]);
+    assertElementsEquals(msg.getRepeatedSint64List(), [-0x8000000000000000]);
+    assertElementsEquals(msg.getRepeatedFixed32List(), [1234]);
+    assertElementsEquals(msg.getRepeatedFixed64List(), [0x1234567800000000]);
+    assertElementsEquals(msg.getRepeatedSfixed32List(), [-1234]);
+    assertElementsEquals(msg.getRepeatedSfixed64List(), [-0x1234567800000000]);
+    assertElementsEquals(msg.getRepeatedFloatList(), [1.5]);
+    assertElementsEquals(msg.getRepeatedDoubleList(), [-1.5]);
+    assertElementsEquals(msg.getRepeatedBoolList(), [true]);
+    assertElementsEquals(msg.getRepeatedStringList(), ['hello world']);
+    assertEquals(msg.getRepeatedBytesList().length, 1);
+    assertEquals(true, bytesCompare(msg.getRepeatedBytesList()[0], BYTES));
+    assertEquals(msg.getRepeatedForeignMessageList().length, 1);
+    assertEquals(msg.getRepeatedForeignMessageList()[0].getC(), 1000);
+    assertElementsEquals(msg.getRepeatedForeignEnumList(),
+        [proto.jspb.test.Proto3Enum.PROTO3_BAR]);
+
+    assertEquals(msg.getOneofString(), 'asdf');
+  });
+
+
+  /**
+   * Test that oneofs continue to have a notion of field presence.
+   */
+  it('testOneofs', function() {
+    var msg = new proto.jspb.test.TestProto3();
+
+    assertEquals(msg.getOneofUint32(), 0);
+    assertEquals(msg.getOneofForeignMessage(), undefined);
+    assertEquals(msg.getOneofString(), '');
+    assertEquals(msg.getOneofBytes(), '');
+    assertFalse(msg.hasOneofUint32());
+    assertFalse(msg.hasOneofString());
+    assertFalse(msg.hasOneofBytes());
+
+    msg.setOneofUint32(42);
+    assertEquals(msg.getOneofUint32(), 42);
+    assertEquals(msg.getOneofForeignMessage(), undefined);
+    assertEquals(msg.getOneofString(), '');
+    assertEquals(msg.getOneofBytes(), '');
+    assertTrue(msg.hasOneofUint32());
+    assertFalse(msg.hasOneofString());
+    assertFalse(msg.hasOneofBytes());
+
+
+    var submsg = new proto.jspb.test.ForeignMessage();
+    msg.setOneofForeignMessage(submsg);
+    assertEquals(msg.getOneofUint32(), 0);
+    assertEquals(msg.getOneofForeignMessage(), submsg);
+    assertEquals(msg.getOneofString(), '');
+    assertEquals(msg.getOneofBytes(), '');
+    assertFalse(msg.hasOneofUint32());
+    assertFalse(msg.hasOneofString());
+    assertFalse(msg.hasOneofBytes());
+
+    msg.setOneofString('hello');
+    assertEquals(msg.getOneofUint32(), 0);
+    assertEquals(msg.getOneofForeignMessage(), undefined);
+    assertEquals(msg.getOneofString(), 'hello');
+    assertEquals(msg.getOneofBytes(), '');
+    assertFalse(msg.hasOneofUint32());
+    assertTrue(msg.hasOneofString());
+    assertFalse(msg.hasOneofBytes());
+
+    msg.setOneofBytes(goog.crypt.base64.encodeString('\u00FF\u00FF'));
+    assertEquals(msg.getOneofUint32(), 0);
+    assertEquals(msg.getOneofForeignMessage(), undefined);
+    assertEquals(msg.getOneofString(), '');
+    assertEquals(msg.getOneofBytes_asB64(),
+        goog.crypt.base64.encodeString('\u00FF\u00FF'));
+    assertFalse(msg.hasOneofUint32());
+    assertFalse(msg.hasOneofString());
+    assertTrue(msg.hasOneofBytes());
+  });
+
+
+  /**
+   * Test that "default"-valued primitive fields are not emitted on the wire.
+   */
+  it('testNoSerializeDefaults', function() {
+    var msg = new proto.jspb.test.TestProto3();
+
+    // Set each primitive to a non-default value, then back to its default, to
+    // ensure that the serialization is actually checking the value and not just
+    // whether it has ever been set.
+    msg.setOptionalInt32(42);
+    msg.setOptionalInt32(0);
+    msg.setOptionalDouble(3.14);
+    msg.setOptionalDouble(0.0);
+    msg.setOptionalBool(true);
+    msg.setOptionalBool(false);
+    msg.setOptionalString('hello world');
+    msg.setOptionalString('');
+    msg.setOptionalBytes(goog.crypt.base64.encodeString('\u00FF\u00FF'));
+    msg.setOptionalBytes('');
+    msg.setOptionalForeignMessage(new proto.jspb.test.ForeignMessage());
+    msg.setOptionalForeignMessage(null);
+    msg.setOptionalForeignEnum(proto.jspb.test.Proto3Enum.PROTO3_BAR);
+    msg.setOptionalForeignEnum(proto.jspb.test.Proto3Enum.PROTO3_FOO);
+    msg.setOneofUint32(32);
+    msg.clearOneofUint32();
+
+
+    var serialized = msg.serializeBinary();
+    assertEquals(0, serialized.length);
+  });
+
+  /**
+   * Test that base64 string and Uint8Array are interchangeable in bytes fields.
+   */
+  it('testBytesFieldsInterop', function() {
+    var msg = new proto.jspb.test.TestProto3();
+    // Set as a base64 string and check all the getters work.
+    msg.setOptionalBytes(BYTES_B64);
+    assertTrue(bytesCompare(msg.getOptionalBytes_asU8(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes_asB64(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+    // Test binary serialize round trip doesn't break it.
+    msg = proto.jspb.test.TestProto3.deserializeBinary(msg.serializeBinary());
+    assertTrue(bytesCompare(msg.getOptionalBytes_asU8(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes_asB64(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+    msg = new proto.jspb.test.TestProto3();
+    // Set as a Uint8Array and check all the getters work.
+    msg.setOptionalBytes(BYTES);
+    assertTrue(bytesCompare(msg.getOptionalBytes_asU8(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes_asB64(), BYTES));
+    assertTrue(bytesCompare(msg.getOptionalBytes(), BYTES));
+
+  });
+});
diff --git a/js/compatibility_tests/v3.1.0/proto3_test.proto b/js/compatibility_tests/v3.1.0/proto3_test.proto
new file mode 100644
index 00000000..acb67164
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/proto3_test.proto
@@ -0,0 +1,89 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+import "testbinary.proto";
+
+package jspb.test;
+
+message TestProto3 {
+     int32 optional_int32    =  1;
+     int64 optional_int64    =  2;
+    uint32 optional_uint32   =  3;
+    uint64 optional_uint64   =  4;
+    sint32 optional_sint32   =  5;
+    sint64 optional_sint64   =  6;
+   fixed32 optional_fixed32  =  7;
+   fixed64 optional_fixed64  =  8;
+  sfixed32 optional_sfixed32 =  9;
+  sfixed64 optional_sfixed64 = 10;
+     float optional_float    = 11;
+    double optional_double   = 12;
+      bool optional_bool     = 13;
+    string optional_string   = 14;
+     bytes optional_bytes    = 15;
+
+  ForeignMessage optional_foreign_message = 19;
+  Proto3Enum     optional_foreign_enum    = 22;
+
+  repeated    int32 repeated_int32    = 31;
+  repeated    int64 repeated_int64    = 32;
+  repeated   uint32 repeated_uint32   = 33;
+  repeated   uint64 repeated_uint64   = 34;
+  repeated   sint32 repeated_sint32   = 35;
+  repeated   sint64 repeated_sint64   = 36;
+  repeated  fixed32 repeated_fixed32  = 37;
+  repeated  fixed64 repeated_fixed64  = 38;
+  repeated sfixed32 repeated_sfixed32 = 39;
+  repeated sfixed64 repeated_sfixed64 = 40;
+  repeated    float repeated_float    = 41;
+  repeated   double repeated_double   = 42;
+  repeated     bool repeated_bool     = 43;
+  repeated   string repeated_string   = 44;
+  repeated    bytes repeated_bytes    = 45;
+
+  repeated ForeignMessage repeated_foreign_message = 49;
+  repeated Proto3Enum     repeated_foreign_enum    = 52;
+
+
+  oneof oneof_field {
+    uint32 oneof_uint32 = 111;
+    ForeignMessage oneof_foreign_message = 112;
+    string oneof_string = 113;
+    bytes oneof_bytes = 114;
+  }
+}
+
+enum Proto3Enum {
+  PROTO3_FOO = 0;
+  PROTO3_BAR = 1;
+  PROTO3_BAZ = 2;
+}
diff --git a/js/compatibility_tests/v3.1.0/test.proto b/js/compatibility_tests/v3.1.0/test.proto
new file mode 100644
index 00000000..48cb37e1
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/test.proto
@@ -0,0 +1,262 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Author: mwr@google.com (Mark Rawling)
+
+syntax = "proto2";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+import "google/protobuf/descriptor.proto";
+
+package jspb.test;
+
+message Empty {
+}
+
+enum OuterEnum {
+  FOO = 1;
+  BAR = 2;
+}
+
+message EnumContainer {
+  optional OuterEnum outer_enum = 1;
+}
+
+message Simple1 {
+  required string a_string = 1;
+  repeated string a_repeated_string = 2;
+  optional bool a_boolean = 3;
+}
+
+// A message that differs from Simple1 only by name
+message Simple2 {
+  required string a_string = 1;
+  repeated string a_repeated_string = 2;
+}
+
+message SpecialCases {
+  required string normal = 1;
+  // Examples of Js reserved names that are converted to pb_<name>.
+  required string default = 2;
+  required string function = 3;
+  required string var = 4;
+}
+
+message OptionalFields {
+  message Nested {
+    optional int32 an_int = 1;
+  }
+  optional string a_string = 1;
+  required bool a_bool = 2;
+  optional Nested a_nested_message = 3;
+  repeated Nested a_repeated_message = 4;
+  repeated string a_repeated_string = 5;
+}
+
+message HasExtensions {
+  optional string str1 = 1;
+  optional string str2 = 2;
+  optional string str3 = 3;
+  extensions 10 to max;
+}
+
+message Complex {
+  message Nested {
+    required int32 an_int = 2;
+  }
+  required string a_string = 1;
+  required bool an_out_of_order_bool = 9;
+  optional Nested a_nested_message = 4;
+  repeated Nested a_repeated_message = 5;
+  repeated string a_repeated_string = 7;
+}
+
+message OuterMessage {
+  // Make sure this doesn't conflict with the other Complex message.
+  message Complex {
+    optional int32 inner_complex_field = 1;
+  }
+}
+
+message IsExtension {
+  extend HasExtensions {
+    optional IsExtension ext_field = 100;
+  }
+  optional string ext1 = 1;
+
+  // Extensions of proto2 Descriptor messages will be ignored.
+  extend google.protobuf.EnumOptions {
+    optional string simple_option = 42113038;
+  }
+}
+
+message IndirectExtension {
+  extend HasExtensions {
+    optional Simple1 simple = 101;
+    optional string str = 102;
+    repeated string repeated_str = 103;
+    repeated Simple1 repeated_simple = 104;
+  }
+}
+
+extend HasExtensions {
+  optional Simple1 simple1 = 105;
+}
+
+message DefaultValues {
+  enum Enum {
+    E1 = 13;
+    E2 = 77;
+  }
+  optional string string_field = 1 [default="default<>\'\"abc"];
+  optional bool bool_field = 2 [default=true];
+  optional int64 int_field = 3 [default=11];
+  optional Enum enum_field = 4 [default=E1];
+  optional string empty_field = 6 [default=""];
+  optional bytes bytes_field = 8 [default="moo"]; // Base64 encoding is "bW9v"
+}
+
+message FloatingPointFields {
+  optional float optional_float_field = 1;
+  required float required_float_field = 2;
+  repeated float repeated_float_field = 3;
+  optional float default_float_field = 4 [default = 2.0];
+  optional double optional_double_field = 5;
+  required double required_double_field = 6;
+  repeated double repeated_double_field = 7;
+  optional double default_double_field = 8 [default = 2.0];
+}
+
+message TestClone {
+  optional string str = 1;
+  optional Simple1 simple1 = 3;
+  repeated Simple1 simple2 = 5;
+  optional bytes bytes_field = 6;
+  optional string unused = 7;
+  extensions 10 to max;
+}
+
+message CloneExtension {
+  extend TestClone {
+    optional CloneExtension ext_field = 100;
+  }
+  optional string ext = 2;
+}
+
+message TestGroup {
+  repeated group RepeatedGroup = 1 {
+    required string id = 1;
+    repeated bool some_bool = 2;
+  }
+  required group RequiredGroup = 2 {
+    required string id = 1;
+  }
+  optional group OptionalGroup = 3 {
+    required string id = 1;
+  }
+  optional string id = 4;
+  required Simple2 required_simple = 5;
+  optional Simple2 optional_simple = 6;
+}
+
+message TestGroup1 {
+  optional TestGroup.RepeatedGroup group = 1;
+}
+
+message TestReservedNames {
+  optional int32 extension = 1;
+  extensions 10 to max;
+}
+
+message TestReservedNamesExtension {
+  extend TestReservedNames {
+    optional int32 foo = 10;
+  }
+}
+
+message TestMessageWithOneof {
+
+  oneof partial_oneof {
+    string pone = 3;
+    string pthree = 5;
+  }
+
+  oneof recursive_oneof {
+    TestMessageWithOneof rone = 6;
+    string rtwo = 7;
+  }
+
+  optional bool normal_field = 8;
+  repeated string repeated_field = 9;
+
+  oneof default_oneof_a {
+    int32 aone = 10 [default = 1234];
+    int32 atwo = 11;
+  }
+
+  oneof default_oneof_b {
+    int32 bone = 12;
+    int32 btwo = 13 [default = 1234];
+  }
+}
+
+message TestEndsWithBytes {
+  optional int32 value = 1;
+  optional bytes data = 2;
+}
+
+message TestMapFieldsNoBinary {
+  map<string, string> map_string_string = 1;
+  map<string, int32> map_string_int32 = 2;
+  map<string, int64> map_string_int64 = 3;
+  map<string, bool> map_string_bool = 4;
+  map<string, double> map_string_double = 5;
+  map<string, MapValueEnumNoBinary> map_string_enum = 6;
+  map<string, MapValueMessageNoBinary> map_string_msg = 7;
+
+  map<int32, string> map_int32_string = 8;
+  map<int64, string> map_int64_string = 9;
+  map<bool, string> map_bool_string = 10;
+
+  optional TestMapFieldsNoBinary test_map_fields = 11;
+  map<string, TestMapFieldsNoBinary> map_string_testmapfields = 12;
+}
+
+enum MapValueEnumNoBinary {
+  MAP_VALUE_FOO_NOBINARY = 0;
+  MAP_VALUE_BAR_NOBINARY = 1;
+  MAP_VALUE_BAZ_NOBINARY = 2;
+}
+
+message MapValueMessageNoBinary {
+  optional int32 foo = 1;
+}
diff --git a/js/compatibility_tests/v3.1.0/test2.proto b/js/compatibility_tests/v3.1.0/test2.proto
new file mode 100644
index 00000000..44e55eff
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/test2.proto
@@ -0,0 +1,54 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto2";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.test;
+
+message TestExtensionsMessage {
+  optional int32 intfield = 1;
+  extensions 100 to max;
+}
+
+message ExtensionMessage {
+  extend TestExtensionsMessage {
+    optional ExtensionMessage ext_field = 100;
+  }
+  optional string ext1 = 1;
+}
+
+// Floating extensions are only supported when generating a _lib.js library.
+extend TestExtensionsMessage {
+  optional ExtensionMessage floating_msg_field = 101;
+  optional string floating_str_field = 102;
+}
diff --git a/js/compatibility_tests/v3.1.0/test3.proto b/js/compatibility_tests/v3.1.0/test3.proto
new file mode 100644
index 00000000..940a552e
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/test3.proto
@@ -0,0 +1,53 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto2";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.exttest;
+
+message TestExtensionsMessage {
+  optional int32 intfield = 1;
+  extensions 100 to max;
+}
+
+message ExtensionMessage {
+  extend TestExtensionsMessage {
+    optional ExtensionMessage ext_field = 100;
+  }
+  optional string ext1 = 1;
+}
+
+extend TestExtensionsMessage {
+  optional ExtensionMessage floating_msg_field = 101;
+  optional string floating_str_field = 102;
+}
diff --git a/js/compatibility_tests/v3.1.0/test4.proto b/js/compatibility_tests/v3.1.0/test4.proto
new file mode 100644
index 00000000..cf2451e9
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/test4.proto
@@ -0,0 +1,42 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto2";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.exttest;
+
+import "test3.proto";
+
+extend TestExtensionsMessage {
+  optional ExtensionMessage floating_msg_field_two = 103;
+}
diff --git a/js/compatibility_tests/v3.1.0/test5.proto b/js/compatibility_tests/v3.1.0/test5.proto
new file mode 100644
index 00000000..34979517
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/test5.proto
@@ -0,0 +1,44 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto2";
+
+option java_package = "com.google.apps.jspb.proto";
+option java_multiple_files = true;
+
+package jspb.exttest.beta;
+
+message TestBetaExtensionsMessage {
+  extensions 100 to max;
+}
+
+extend TestBetaExtensionsMessage {
+  optional string floating_str_field = 101;
+}
diff --git a/js/compatibility_tests/v3.1.0/testbinary.proto b/js/compatibility_tests/v3.1.0/testbinary.proto
new file mode 100644
index 00000000..116f17fb
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/testbinary.proto
@@ -0,0 +1,212 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// LINT: ALLOW_GROUPS
+
+syntax = "proto2";
+
+
+package jspb.test;
+
+// These types are borrowed from `unittest.proto` in the protobuf tree. We want
+// to ensure that the binary-format support will handle all field types
+// properly.
+message TestAllTypes {
+  optional    int32 optional_int32    =  1;
+  optional    int64 optional_int64    =  2;
+  optional   uint32 optional_uint32   =  3;
+  optional   uint64 optional_uint64   =  4;
+  optional   sint32 optional_sint32   =  5;
+  optional   sint64 optional_sint64   =  6;
+  optional  fixed32 optional_fixed32  =  7;
+  optional  fixed64 optional_fixed64  =  8;
+  optional sfixed32 optional_sfixed32 =  9;
+  optional sfixed64 optional_sfixed64 = 10;
+  optional    float optional_float    = 11;
+  optional   double optional_double   = 12;
+  optional     bool optional_bool     = 13;
+  optional   string optional_string   = 14;
+  optional    bytes optional_bytes    = 15;
+  optional group OptionalGroup = 16 {
+    optional int32 a = 17;
+  }
+
+  optional ForeignMessage                       optional_foreign_message = 19;
+  optional ForeignEnum                          optional_foreign_enum    = 22;
+
+  // Repeated
+  repeated    int32 repeated_int32    = 31;
+  repeated    int64 repeated_int64    = 32;
+  repeated   uint32 repeated_uint32   = 33;
+  repeated   uint64 repeated_uint64   = 34;
+  repeated   sint32 repeated_sint32   = 35;
+  repeated   sint64 repeated_sint64   = 36;
+  repeated  fixed32 repeated_fixed32  = 37;
+  repeated  fixed64 repeated_fixed64  = 38;
+  repeated sfixed32 repeated_sfixed32 = 39;
+  repeated sfixed64 repeated_sfixed64 = 40;
+  repeated    float repeated_float    = 41;
+  repeated   double repeated_double   = 42;
+  repeated     bool repeated_bool     = 43;
+  repeated   string repeated_string   = 44;
+  repeated    bytes repeated_bytes    = 45;
+
+  repeated group RepeatedGroup = 46 {
+    optional int32 a = 47;
+  }
+
+  repeated ForeignMessage                       repeated_foreign_message = 49;
+  repeated ForeignEnum                          repeated_foreign_enum    = 52;
+
+  // Packed repeated
+  repeated    int32 packed_repeated_int32    = 61 [packed=true];
+  repeated    int64 packed_repeated_int64    = 62 [packed=true];
+  repeated   uint32 packed_repeated_uint32   = 63 [packed=true];
+  repeated   uint64 packed_repeated_uint64   = 64 [packed=true];
+  repeated   sint32 packed_repeated_sint32   = 65 [packed=true];
+  repeated   sint64 packed_repeated_sint64   = 66 [packed=true];
+  repeated  fixed32 packed_repeated_fixed32  = 67 [packed=true];
+  repeated  fixed64 packed_repeated_fixed64  = 68 [packed=true];
+  repeated sfixed32 packed_repeated_sfixed32 = 69 [packed=true];
+  repeated sfixed64 packed_repeated_sfixed64 = 70 [packed=true];
+  repeated    float packed_repeated_float    = 71 [packed=true];
+  repeated   double packed_repeated_double   = 72 [packed=true];
+  repeated     bool packed_repeated_bool     = 73 [packed=true];
+
+  oneof oneof_field {
+    uint32 oneof_uint32 = 111;
+    ForeignMessage oneof_foreign_message = 112;
+    string oneof_string = 113;
+    bytes oneof_bytes = 114;
+  }
+
+}
+
+message ForeignMessage {
+  optional int32 c = 1;
+}
+
+enum ForeignEnum {
+  FOREIGN_FOO = 4;
+  FOREIGN_BAR = 5;
+  FOREIGN_BAZ = 6;
+}
+
+message TestExtendable {
+  extensions 1 to max;
+}
+
+message ExtendsWithMessage {
+  extend TestExtendable {
+    optional ExtendsWithMessage optional_extension = 19;
+    repeated ExtendsWithMessage repeated_extension = 49;
+  }
+  optional int32 foo = 1;
+}
+
+extend TestExtendable {
+  optional    int32 extend_optional_int32    =  1;
+  optional    int64 extend_optional_int64    =  2;
+  optional   uint32 extend_optional_uint32   =  3;
+  optional   uint64 extend_optional_uint64   =  4;
+  optional   sint32 extend_optional_sint32   =  5;
+  optional   sint64 extend_optional_sint64   =  6;
+  optional  fixed32 extend_optional_fixed32  =  7;
+  optional  fixed64 extend_optional_fixed64  =  8;
+  optional sfixed32 extend_optional_sfixed32 =  9;
+  optional sfixed64 extend_optional_sfixed64 = 10;
+  optional    float extend_optional_float    = 11;
+  optional   double extend_optional_double   = 12;
+  optional     bool extend_optional_bool     = 13;
+  optional   string extend_optional_string   = 14;
+  optional    bytes extend_optional_bytes    = 15;
+  optional ForeignEnum extend_optional_foreign_enum    = 22;
+
+  repeated    int32 extend_repeated_int32    = 31;
+  repeated    int64 extend_repeated_int64    = 32;
+  repeated   uint32 extend_repeated_uint32   = 33;
+  repeated   uint64 extend_repeated_uint64   = 34;
+  repeated   sint32 extend_repeated_sint32   = 35;
+  repeated   sint64 extend_repeated_sint64   = 36;
+  repeated  fixed32 extend_repeated_fixed32  = 37;
+  repeated  fixed64 extend_repeated_fixed64  = 38;
+  repeated sfixed32 extend_repeated_sfixed32 = 39;
+  repeated sfixed64 extend_repeated_sfixed64 = 40;
+  repeated    float extend_repeated_float    = 41;
+  repeated   double extend_repeated_double   = 42;
+  repeated     bool extend_repeated_bool     = 43;
+  repeated   string extend_repeated_string   = 44;
+  repeated    bytes extend_repeated_bytes    = 45;
+  repeated ForeignEnum extend_repeated_foreign_enum    = 52;
+
+  repeated    int32 extend_packed_repeated_int32    = 61 [packed=true];
+  repeated    int64 extend_packed_repeated_int64    = 62 [packed=true];
+  repeated   uint32 extend_packed_repeated_uint32   = 63 [packed=true];
+  repeated   uint64 extend_packed_repeated_uint64   = 64 [packed=true];
+  repeated   sint32 extend_packed_repeated_sint32   = 65 [packed=true];
+  repeated   sint64 extend_packed_repeated_sint64   = 66 [packed=true];
+  repeated  fixed32 extend_packed_repeated_fixed32  = 67 [packed=true];
+  repeated  fixed64 extend_packed_repeated_fixed64  = 68 [packed=true];
+  repeated sfixed32 extend_packed_repeated_sfixed32 = 69 [packed=true];
+  repeated sfixed64 extend_packed_repeated_sfixed64 = 70 [packed=true];
+  repeated    float extend_packed_repeated_float    = 71 [packed=true];
+  repeated   double extend_packed_repeated_double   = 72 [packed=true];
+  repeated     bool extend_packed_repeated_bool     = 73 [packed=true];
+  repeated ForeignEnum extend_packed_repeated_foreign_enum    = 82
+      [packed=true];
+
+}
+
+message TestMapFields {
+  map<string, string> map_string_string = 1;
+  map<string, int32> map_string_int32 = 2;
+  map<string, int64> map_string_int64 = 3;
+  map<string, bool> map_string_bool = 4;
+  map<string, double> map_string_double = 5;
+  map<string, MapValueEnum> map_string_enum = 6;
+  map<string, MapValueMessage> map_string_msg = 7;
+
+  map<int32, string> map_int32_string = 8;
+  map<int64, string> map_int64_string = 9;
+  map<bool, string> map_bool_string = 10;
+
+  optional TestMapFields test_map_fields = 11;
+  map<string, TestMapFields> map_string_testmapfields = 12;
+}
+
+enum MapValueEnum {
+  MAP_VALUE_FOO = 0;
+  MAP_VALUE_BAR = 1;
+  MAP_VALUE_BAZ = 2;
+}
+
+message MapValueMessage {
+  optional int32 foo = 1;
+}
diff --git a/js/compatibility_tests/v3.1.0/testempty.proto b/js/compatibility_tests/v3.1.0/testempty.proto
new file mode 100644
index 00000000..960bce4e
--- /dev/null
+++ b/js/compatibility_tests/v3.1.0/testempty.proto
@@ -0,0 +1,34 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto2";
+
+package javatests.com.google.apps.jspb;
+