First pass at making field access simpler.

This is definitely not ready to ship - I'm "troubled" by the disconnect between a list of fields in declaration order, and a mapping of field accessors by field number/name. Discussion required, but I find that easier when we've got code to look at :)

2 files changed, 233 insertions, 0 deletions

diff --git a/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs b/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs
index 0aff0a6c..ed4291a4 100644
--- a/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs
+++ b/csharp/src/Google.Protobuf.Test/Reflection/DescriptorsTest.cs
@@ -33,6 +33,7 @@
 using System.Linq;
 using Google.Protobuf.TestProtos;
 using NUnit.Framework;
+using UnitTest.Issues.TestProtos;
 
 namespace Google.Protobuf.Reflection
 {
@@ -220,5 +221,19 @@ namespace Google.Protobuf.Reflection
 
             CollectionAssert.AreEquivalent(expectedFields, descriptor.Fields);
         }
+
+        [Test]
+        public void ConstructionWithoutGeneratedCodeInfo()
+        {
+            var data = UnittestIssues.Descriptor.Proto.ToByteArray();
+            var newDescriptor = Google.Protobuf.Reflection.FileDescriptor.InternalBuildGeneratedFileFrom(data, new Reflection.FileDescriptor[] { }, null);
+
+            // We should still be able to get at a field...
+            var messageDescriptor = newDescriptor.FindTypeByName<MessageDescriptor>("ItemField");
+            var fieldDescriptor = messageDescriptor.FindFieldByName("item");
+            // But there shouldn't be an accessor (or a generated type for the message)
+            Assert.IsNull(fieldDescriptor.Accessor);
+            Assert.IsNull(messageDescriptor.GeneratedType);
+        }
     }
 }
\ No newline at end of file
diff --git a/csharp/src/Google.Protobuf.Test/Reflection/FieldAccessTest.cs b/csharp/src/Google.Protobuf.Test/Reflection/FieldAccessTest.cs
new file mode 100644
index 00000000..5d6e777f
--- /dev/null
+++ b/csharp/src/Google.Protobuf.Test/Reflection/FieldAccessTest.cs
@@ -0,0 +1,218 @@
+#region Copyright notice and license
+// Protocol Buffers - Google's data interchange format
+// Copyright 2015 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.
+#endregion
+
+using Google.Protobuf.TestProtos;
+using NUnit.Framework;
+using System;
+using System.Collections;
+using System.Collections.Generic;
+
+namespace Google.Protobuf.Reflection
+{
+    public class FieldAccessTest
+    {
+        [Test]
+        public void GetValue()
+        {
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var fields = TestAllTypes.Descriptor.FieldAccessors;
+            Assert.AreEqual(message.SingleBool, fields[TestAllTypes.SingleBoolFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleBytes, fields[TestAllTypes.SingleBytesFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleDouble, fields[TestAllTypes.SingleDoubleFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleFixed32, fields[TestAllTypes.SingleFixed32FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleFixed64, fields[TestAllTypes.SingleFixed64FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleFloat, fields[TestAllTypes.SingleFloatFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleForeignEnum, fields[TestAllTypes.SingleForeignEnumFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleForeignMessage, fields[TestAllTypes.SingleForeignMessageFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleImportEnum, fields[TestAllTypes.SingleImportEnumFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleImportMessage, fields[TestAllTypes.SingleImportMessageFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleInt32, fields[TestAllTypes.SingleInt32FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleInt64, fields[TestAllTypes.SingleInt64FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleNestedEnum, fields[TestAllTypes.SingleNestedEnumFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleNestedMessage, fields[TestAllTypes.SingleNestedMessageFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SinglePublicImportMessage, fields[TestAllTypes.SinglePublicImportMessageFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleSint32, fields[TestAllTypes.SingleSint32FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleSint64, fields[TestAllTypes.SingleSint64FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleString, fields[TestAllTypes.SingleStringFieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleSfixed32, fields[TestAllTypes.SingleSfixed32FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleSfixed64, fields[TestAllTypes.SingleSfixed64FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleUint32, fields[TestAllTypes.SingleUint32FieldNumber].GetValue(message));
+            Assert.AreEqual(message.SingleUint64, fields[TestAllTypes.SingleUint64FieldNumber].GetValue(message));
+            Assert.AreEqual(message.OneofBytes, fields[TestAllTypes.OneofBytesFieldNumber].GetValue(message));
+            Assert.AreEqual(message.OneofString, fields[TestAllTypes.OneofStringFieldNumber].GetValue(message));
+            Assert.AreEqual(message.OneofNestedMessage, fields[TestAllTypes.OneofNestedMessageFieldNumber].GetValue(message));
+            Assert.AreEqual(message.OneofUint32, fields[TestAllTypes.OneofUint32FieldNumber].GetValue(message));
+
+            // Just one example for repeated fields - they're all just returning the list
+            var list = (IList) fields[TestAllTypes.RepeatedInt32FieldNumber].GetValue(message);
+            Assert.AreEqual(message.RepeatedInt32, list);
+            Assert.AreEqual(message.RepeatedInt32[0], list[0]); // Just in case there was any doubt...
+
+            // Just a single map field, for the same reason
+            var mapMessage = new TestMap { MapStringString = { { "key1", "value1" }, { "key2", "value2" } } };
+            fields = TestMap.Descriptor.FieldAccessors;
+            var dictionary = (IDictionary) fields[TestMap.MapStringStringFieldNumber].GetValue(mapMessage);
+            Assert.AreEqual(mapMessage.MapStringString, dictionary);
+            Assert.AreEqual("value1", dictionary["key1"]);
+        }
+
+        [Test]
+        public void Clear()
+        {
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var fields = TestAllTypes.Descriptor.FieldAccessors;
+            fields[TestAllTypes.SingleBoolFieldNumber].Clear(message);
+            fields[TestAllTypes.SingleInt32FieldNumber].Clear(message);
+            fields[TestAllTypes.SingleStringFieldNumber].Clear(message);
+            fields[TestAllTypes.SingleBytesFieldNumber].Clear(message);
+            fields[TestAllTypes.SingleForeignEnumFieldNumber].Clear(message);
+            fields[TestAllTypes.SingleForeignMessageFieldNumber].Clear(message);
+            fields[TestAllTypes.RepeatedDoubleFieldNumber].Clear(message);
+
+            var expected = new TestAllTypes(SampleMessages.CreateFullTestAllTypes())
+            {
+                SingleBool = false,
+                SingleInt32 = 0,
+                SingleString = "",
+                SingleBytes = ByteString.Empty,
+                SingleForeignEnum = 0,
+                SingleForeignMessage = null,
+            };
+            expected.RepeatedDouble.Clear();
+
+            Assert.AreEqual(expected, message);
+
+            // Separately, maps.
+            var mapMessage = new TestMap { MapStringString = { { "key1", "value1" }, { "key2", "value2" } } };
+            fields = TestMap.Descriptor.FieldAccessors;
+            fields[TestMap.MapStringStringFieldNumber].Clear(mapMessage);
+            Assert.AreEqual(0, mapMessage.MapStringString.Count);
+        }
+
+        [Test]
+        public void SetValue_SingleFields()
+        {
+            // Just a sample (primitives, messages, enums, strings, byte strings)
+            var message = SampleMessages.CreateFullTestAllTypes();
+            var fields = TestAllTypes.Descriptor.FieldAccessors;
+            fields[TestAllTypes.SingleBoolFieldNumber].SetValue(message, false);
+            fields[TestAllTypes.SingleInt32FieldNumber].SetValue(message, 500);
+            fields[TestAllTypes.SingleStringFieldNumber].SetValue(message, "It's a string");
+            fields[TestAllTypes.SingleBytesFieldNumber].SetValue(message, ByteString.CopyFrom(99, 98, 97));
+            fields[TestAllTypes.SingleForeignEnumFieldNumber].SetValue(message, ForeignEnum.FOREIGN_FOO);
+            fields[TestAllTypes.SingleForeignMessageFieldNumber].SetValue(message, new ForeignMessage { C = 12345 });
+            fields[TestAllTypes.SingleDoubleFieldNumber].SetValue(message, 20150701.5);
+
+            var expected = new TestAllTypes(SampleMessages.CreateFullTestAllTypes())
+            {
+                SingleBool = false,
+                SingleInt32 = 500,
+                SingleString = "It's a string",
+                SingleBytes = ByteString.CopyFrom(99, 98, 97),
+                SingleForeignEnum = ForeignEnum.FOREIGN_FOO,
+                SingleForeignMessage = new ForeignMessage { C = 12345 },
+                SingleDouble = 20150701.5
+            };
+
+            Assert.AreEqual(expected, message);
+        }
+
+        [Test]
+        public void SetValue_SingleFields_WrongType()
+        {
+            IMessage message = SampleMessages.CreateFullTestAllTypes();
+            var fields = message.Descriptor.FieldAccessors;
+            Assert.Throws<InvalidCastException>(() => fields[TestAllTypes.SingleBoolFieldNumber].SetValue(message, "This isn't a bool"));
+        }
+
+        [Test]
+        public void SetValue_MapFields()
+        {
+            IMessage message = new TestMap();
+            var fields = message.Descriptor.FieldAccessors;
+            Assert.Throws<InvalidOperationException>(() => fields[TestMap.MapStringStringFieldNumber].SetValue(message, new Dictionary<string, string>()));
+        }
+
+        [Test]
+        public void SetValue_RepeatedFields()
+        {
+            IMessage message = SampleMessages.CreateFullTestAllTypes();
+            var fields = message.Descriptor.FieldAccessors;
+            Assert.Throws<InvalidOperationException>(() => fields[TestAllTypes.RepeatedDoubleFieldNumber].SetValue(message, new double[10]));
+        }
+
+        [Test]
+        public void GetValue_IncorrectType()
+        {
+            IMessage message = SampleMessages.CreateFullTestAllTypes();
+            var fields = message.Descriptor.FieldAccessors;
+            Assert.Throws<InvalidCastException>(() => fields[TestAllTypes.SingleBoolFieldNumber].GetValue(new TestMap()));
+        }
+
+        [Test]
+        public void Oneof()
+        {
+            var message = new TestAllTypes();
+            var descriptor = TestAllTypes.Descriptor;
+            Assert.AreEqual(1, descriptor.Oneofs.Count);
+            var oneof = descriptor.Oneofs[0];
+            Assert.AreEqual("oneof_field", oneof.Name);
+            Assert.IsNull(oneof.Accessor.GetCaseFieldDescriptor(message));
+
+            message.OneofString = "foo";
+            Assert.AreSame(descriptor.FieldAccessors[TestAllTypes.OneofStringFieldNumber].Descriptor, oneof.Accessor.GetCaseFieldDescriptor(message));
+
+            message.OneofUint32 = 10;
+            Assert.AreSame(descriptor.FieldAccessors[TestAllTypes.OneofUint32FieldNumber].Descriptor, oneof.Accessor.GetCaseFieldDescriptor(message));
+
+            oneof.Accessor.Clear(message);
+            Assert.AreEqual(TestAllTypes.OneofFieldOneofCase.None, message.OneofFieldCase);
+        }
+
+        [Test]
+        public void FieldAccessor_ByName()
+        {
+            var descriptor = TestAllTypes.Descriptor;
+            Assert.AreSame(
+                descriptor.FieldAccessors[TestAllTypes.SingleBoolFieldNumber],
+                descriptor.FieldAccessors["single_bool"]);
+        }
+
+        [Test]
+        public void FieldAccessor_NotFound()
+        {
+            var descriptor = TestAllTypes.Descriptor;
+            Assert.Throws<KeyNotFoundException>(() => descriptor.FieldAccessors[999999].ToString());
+            Assert.Throws<KeyNotFoundException>(() => descriptor.FieldAccessors["not found"].ToString());
+        }
+    }
+}