Add unit tests for Gradients

7 files changed, 148 insertions, 12 deletions

diff --git a/tensorflow/java/BUILD b/tensorflow/java/BUILD
index 73e210fae0..7ceba3903d 100644
--- a/tensorflow/java/BUILD
+++ b/tensorflow/java/BUILD
@@ -292,6 +292,19 @@ tf_java_test(
     ],
 )
 
+tf_java_test(
+    name = "GradientsTest",
+    size = "small",
+    srcs = ["src/test/java/org/tensorflow/op/core/GradientsTest.java"],
+    javacopts = JAVACOPTS,
+    test_class = "org.tensorflow.op.core.GradientsTest",
+    deps = [
+        ":tensorflow",
+        ":testutil",
+        "@junit",
+    ],
+)
+
 filegroup(
     name = "processor_test_resources",
     srcs = glob([
diff --git a/tensorflow/java/src/main/java/org/tensorflow/op/NameScope.java b/tensorflow/java/src/main/java/org/tensorflow/op/NameScope.java
index 92e05d2d6d..95a2a2f9f5 100644
--- a/tensorflow/java/src/main/java/org/tensorflow/op/NameScope.java
+++ b/tensorflow/java/src/main/java/org/tensorflow/op/NameScope.java
@@ -57,7 +57,7 @@ final class NameScope {
     return fullyQualify(makeUnique(actualName));
   }
   
-  String prefix() {
+  String opPrefix() {
     return opPrefix;
   }
 
diff --git a/tensorflow/java/src/main/java/org/tensorflow/op/Scope.java b/tensorflow/java/src/main/java/org/tensorflow/op/Scope.java
index d1ab44c3b2..51a6ce8318 100644
--- a/tensorflow/java/src/main/java/org/tensorflow/op/Scope.java
+++ b/tensorflow/java/src/main/java/org/tensorflow/op/Scope.java
@@ -165,7 +165,7 @@ public final class Scope {
    * }</pre>
    */
   public String prefix() {
-    return nameScope.prefix();
+    return nameScope.opPrefix();
   }
 
   private Scope(Graph graph, NameScope nameScope) {
diff --git a/tensorflow/java/src/main/java/org/tensorflow/op/core/Gradients.java b/tensorflow/java/src/main/java/org/tensorflow/op/core/Gradients.java
index d88dc3ba46..6d71ddfff0 100644
--- a/tensorflow/java/src/main/java/org/tensorflow/op/core/Gradients.java
+++ b/tensorflow/java/src/main/java/org/tensorflow/op/core/Gradients.java
@@ -59,12 +59,12 @@ public class Gradients implements Op, Iterable<Operand<?>> {
      * @param dx partial derivatives of some loss function {@code L} w.r.t. {@code y}
      * @return this option builder
      */
-    public Options dx(Iterable<Operand<?>> dx) {
+    public Options dx(Iterable<? extends Operand<?>> dx) {
       this.dx = dx;
       return this;
     }
     
-    private Iterable<Operand<?>> dx;
+    private Iterable<? extends Operand<?>> dx;
     
     private Options() {
     }
@@ -79,7 +79,7 @@ public class Gradients implements Op, Iterable<Operand<?>> {
    * @param options carries optional attributes values
    * @return a new instance of {@code Gradients}
    */
-  public static Gradients create(Scope scope, Iterable<Operand<?>> y, Iterable<Operand<?>> x, Options... options) {
+  public static Gradients create(Scope scope, Iterable<? extends Operand<?>> y, Iterable<? extends Operand<?>> x, Options... options) {
     Output<?>[] dx = null;
     if (options != null) {
       for (Options opts : options) {
@@ -105,7 +105,7 @@ public class Gradients implements Op, Iterable<Operand<?>> {
    * @return a new instance of {@code Gradients}
    */
   @SuppressWarnings({"unchecked", "rawtypes"})
-  public static Gradients create(Scope scope, Operand<?> y, Iterable<Operand<?>> x, Options... options) {
+  public static Gradients create(Scope scope, Operand<?> y, Iterable<? extends Operand<?>> x, Options... options) {
     return create(scope, (Iterable) Arrays.asList(y), x, options);
   }
 
@@ -113,7 +113,7 @@ public class Gradients implements Op, Iterable<Operand<?>> {
    * @param dx partial derivatives of some loss function {@code L} w.r.t. {@code y}
    * @return builder to add more options to this operation
    */
-  public Options dx(Iterable<Operand<?>> dx) {
+  public static Options dx(Iterable<? extends Operand<?>> dx) {
     return new Options().dx(dx);
   }
 
@@ -135,7 +135,7 @@ public class Gradients implements Op, Iterable<Operand<?>> {
    * <p>
    * Warning: Does not check that the type of the tensor matches T. It is recommended to call
    * this method with an explicit type parameter rather than letting it be inferred, e.g. {@code
-   * gradients.<Integer>dy(0)}
+   * gradients.<Float>dy(0)}
    *
    * @param <T> The expected element type of the tensors produced by this output.
    * @param index The index of the output among the gradients added by this operation
diff --git a/tensorflow/java/src/test/java/org/tensorflow/TestUtil.java b/tensorflow/java/src/test/java/org/tensorflow/TestUtil.java
index 4e84886416..f984c508ee 100644
--- a/tensorflow/java/src/test/java/org/tensorflow/TestUtil.java
+++ b/tensorflow/java/src/test/java/org/tensorflow/TestUtil.java
@@ -24,7 +24,7 @@ public class TestUtil {
 
   public static final class AutoCloseableList<E extends AutoCloseable> extends ArrayList<E>
       implements AutoCloseable {
-    AutoCloseableList(Collection<? extends E> c) {
+    public AutoCloseableList(Collection<? extends E> c) {
       super(c);
     }
 
diff --git a/tensorflow/java/src/test/java/org/tensorflow/op/ScopeTest.java b/tensorflow/java/src/test/java/org/tensorflow/op/ScopeTest.java
index 2057007499..2fb2c1df48 100644
--- a/tensorflow/java/src/test/java/org/tensorflow/op/ScopeTest.java
+++ b/tensorflow/java/src/test/java/org/tensorflow/op/ScopeTest.java
@@ -17,7 +17,7 @@ package org.tensorflow.op;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.fail;
 
 import java.util.HashMap;
@@ -188,8 +188,7 @@ public class ScopeTest {
   public void prefix() {
     try (Graph g = new Graph()) {
       Scope s = new Scope(g);
-      assertNotNull(s.prefix());
-      assertTrue(s.prefix().isEmpty());
+      assertNull(s.prefix());
       
       Scope sub1 = s.withSubScope("sub1");
       assertEquals("sub1", sub1.prefix());
diff --git a/tensorflow/java/src/test/java/org/tensorflow/op/core/GradientsTest.java b/tensorflow/java/src/test/java/org/tensorflow/op/core/GradientsTest.java
new file mode 100644
index 0000000000..2ffc69c209
--- /dev/null
+++ b/tensorflow/java/src/test/java/org/tensorflow/op/core/GradientsTest.java
@@ -0,0 +1,124 @@
+package org.tensorflow.op.core;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+import java.util.Arrays;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.tensorflow.Graph;
+import org.tensorflow.Output;
+import org.tensorflow.Session;
+import org.tensorflow.Tensor;
+import org.tensorflow.Tensors;
+import org.tensorflow.TestUtil;
+import org.tensorflow.op.Scope;
+
+@RunWith(JUnit4.class)
+public class GradientsTest {
+
+  @Test
+  public void createGradients() {
+    try (Graph g = new Graph(); 
+        Session sess = new Session(g)) {
+      Scope scope = new Scope(g);
+
+      Output<Float> x = TestUtil.placeholder(g, "x1", Float.class);
+      Output<Float> y0 = TestUtil.square(g, "y0", x);
+      Output<Float> y1 = TestUtil.square(g, "y1", y0);
+      
+      Gradients grads = Gradients.create(scope, y1, Arrays.asList(x, y0));
+      
+      assertNotNull(grads);
+      assertNotNull(grads.dy());
+      assertEquals(2, grads.dy().size());
+
+      try (Tensor<Float> c = Tensors.create(3.0f);
+          TestUtil.AutoCloseableList<Tensor<?>> outputs = new TestUtil.AutoCloseableList<>(
+              sess.runner()
+                  .feed(x, c)
+                  .fetch(grads.dy(0))
+                  .fetch(grads.dy(1))
+                  .run())) {
+     
+        assertEquals(108.0f, outputs.get(0).floatValue(), 0.0f);
+        assertEquals(18.0f, outputs.get(1).floatValue(), 0.0f);
+      }
+    }
+  }
+
+  @Test
+  public void createGradientsWithSum() {
+    try (Graph g = new Graph();
+        Session sess = new Session(g)) {
+      Scope scope = new Scope(g);
+
+      Output<Float> x = TestUtil.placeholder(g, "x1", Float.class);
+      Output<Float> y0 = TestUtil.square(g, "y0", x);
+      Output<Float> y1 = TestUtil.square(g, "y1", y0);
+      
+      Gradients grads = Gradients.create(scope, Arrays.asList(y0, y1), Arrays.asList(x));
+      
+      assertNotNull(grads);
+      assertNotNull(grads.dy());
+      assertEquals(1, grads.dy().size());
+
+      try (Tensor<Float> c = Tensors.create(3.0f);
+          TestUtil.AutoCloseableList<Tensor<?>> outputs = new TestUtil.AutoCloseableList<>(
+              sess.runner()
+                  .feed(x, c)
+                  .fetch(grads.dy(0))
+                  .run())) {
+     
+        assertEquals(114.0f, outputs.get(0).floatValue(), 0.0f);
+      }
+    }
+  }
+
+  @Test
+  public void createGradientsWithInitialValues() {
+    try (Graph g = new Graph();
+        Session sess = new Session(g)) {
+      Scope scope = new Scope(g);
+
+      Output<Float> x = TestUtil.placeholder(g, "x1", Float.class);
+      Output<Float> y0 = TestUtil.square(g, "y0", x);
+      Output<Float> y1 = TestUtil.square(g, "y1", y0);
+      
+      Gradients grads0 = Gradients.create(scope, y1, Arrays.asList(y0));
+      Gradients grads1 = Gradients.create(scope, y0, Arrays.asList(x), Gradients.dx(grads0.dy()));
+      
+      assertNotNull(grads1);
+      assertNotNull(grads1.dy());
+      assertEquals(1, grads1.dy().size());
+
+      try (Tensor<Float> c = Tensors.create(3.0f);
+          TestUtil.AutoCloseableList<Tensor<?>> outputs = new TestUtil.AutoCloseableList<>(
+              sess.runner()
+                  .feed(x, c)
+                  .fetch(grads1.dy(0))
+                  .run())) {
+     
+        assertEquals(108.0f, outputs.get(0).floatValue(), 0.0f);
+      }
+    }
+  }
+
+  @Test
+  public void createGradientsWithScopeName() {
+    try (Graph g = new Graph()) {
+      Scope scope = new Scope(g);
+
+      Output<Float> x = TestUtil.placeholder(g, "x1", Float.class);
+      Output<Float> y = TestUtil.square(g, "y", x);
+      
+      Scope gradScope = scope.withSubScope("grads").withSubScope("test");
+      Gradients grads = Gradients.create(gradScope, y, Arrays.asList(x));
+      
+      assertTrue(grads.dy(0).op().name().startsWith("grads/test/"));
+    }
+  }
+}