Better cross-environment error messages

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/EagerOperation.java

@@ -68,6 +68,11 @@ public String type() {
     return type;
   }
 
+  @Override
+  public EagerSession env() {
+    return session;
+  }
+
   @Override
   public int numOutputs() {
     return outputHandles.length;

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/EagerOperationBuilder.java

@@ -75,6 +75,7 @@ public EagerOperation build() {
 
   @Override
   public EagerOperationBuilder addInput(Output<?> input) {
+    session.checkInput(input);
     addInput(opHandle, (TFE_TensorHandle) input.getUnsafeNativeHandle());
     return this;
   }
@@ -83,6 +84,7 @@ public EagerOperationBuilder addInput(Output<?> input) {
   public EagerOperationBuilder addInputList(Output<?>[] inputs) {
     TFE_TensorHandle[] inputHandles = new TFE_TensorHandle[inputs.length];
     for (int i = 0; i < inputs.length; ++i) {
+      session.checkInput(inputs[i]);
       inputHandles[i] = (TFE_TensorHandle) inputs[i].getUnsafeNativeHandle();
     }
     addInputList(opHandle, inputHandles);

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/EagerSession.java

@@ -27,6 +27,7 @@
 import org.tensorflow.internal.c_api.TFE_Context;
 import org.tensorflow.internal.c_api.TFE_ContextOptions;
 import org.tensorflow.internal.c_api.TF_Status;
+import org.tensorflow.op.Op;
 import org.tensorflow.op.core.Assign;
 import org.tensorflow.op.core.Placeholder;
 import org.tensorflow.op.core.Variable;
@@ -297,6 +298,13 @@ public boolean isOpEnabled(String opType) {
     }
   }
 
+  @Override
+  public void checkInput(Op input) {
+    if (!input.env().isEager()) {
+      throw new IllegalArgumentException("Can't use graph operation " + input + " in eager mode.");
+    }
+  }
+
   TFE_Context nativeHandle() {
     checkSession();
     return nativeHandle;

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/ExecutionEnvironment.java

@@ -15,7 +15,11 @@
 
 package org.tensorflow;
 
-/** Defines an environment for creating and executing TensorFlow {@link Operation}s. */
+import org.tensorflow.op.Op;
+
+/**
+ * Defines an environment for creating and executing TensorFlow {@link Operation}s.
+ */
 public interface ExecutionEnvironment {
 
   enum Types {
@@ -36,13 +40,23 @@ enum Types {
 
   /**
    * Returns true if the given operation is valid in this execution environment.
+   *
    * @param opType The op to check.
    * @return Whether the given operation is valid in this execution environment.
    */
-  default boolean isOpEnabled(String opType){
+  default boolean isOpEnabled(String opType) {
     return true;
   }
 
+  /**
+   * Checks that {@code input} is valid to use as an input in this execution environment. Throws {@link
+   * IllegalArgumentException} if not.
+   *
+   * @param input The op to check
+   * @throws IllegalArgumentException if input can't be used as an input in this execution environment.
+   */
+  void checkInput(Op input);
+
   /**
    * Get the type of this environment (from the `Environments` enumeration.
    *

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/Graph.java

@@ -158,6 +158,17 @@ public Types environmentType() {
     return Types.GRAPH;
   }
 
+  @Override
+  public void checkInput(Op input) {
+    if (input.env().isEager()) {
+      throw new IllegalArgumentException(
+          "Input " + input + " was from an eager session, can't use in a graph.  Use tf.constantOf(input.asTensor())");
+    }
+    if (input.env() != this) {
+      throw new IllegalArgumentException("Input " + input + " was from a different graph, can't use.");
+    }
+  }
+
   /**
    * Import a representation of a TensorFlow graph.
    *

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/GraphOperation.java

@@ -73,6 +73,13 @@ public String type() {
     }
   }
 
+  @Override
+  public Graph env() {
+    try (Graph.Reference r = graph.ref()) {
+      return graph;
+    }
+  }
+
   @Override
   public int numOutputs() {
     Graph.Reference r = graph.ref();

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/GraphOperationBuilder.java

@@ -92,6 +92,11 @@ public GraphOperationBuilder addControlInput(Operation control) {
       throw new IllegalArgumentException(
           "Only GraphOperation instances can be used as control inputs");
     }
+
+    if (control.env() != graph) {
+      throw new IllegalArgumentException("Control input " + control + " was from a different graph, can't use.");
+    }
+
     Graph.Reference r = graph.ref();
     try {
       addControlInput(unsafeNativeHandle, ((GraphOperation) control).getUnsafeNativeHandle());
@@ -103,6 +108,7 @@ public GraphOperationBuilder addControlInput(Operation control) {
 
   @Override
   public GraphOperationBuilder addInput(Output<?> input) {
+    graph.checkInput(input);
     Graph.Reference r = graph.ref();
     try {
       addInput(unsafeNativeHandle, (TF_Operation) input.getUnsafeNativeHandle(), input.index());
@@ -114,6 +120,10 @@ public GraphOperationBuilder addInput(Output<?> input) {
 
   @Override
   public GraphOperationBuilder addInputList(Output<?>[] inputs) {
+    for (Output<?> input : inputs) {
+      graph.checkInput(input);
+    }
+
     Graph.Reference r = graph.ref();
     try {
       TF_Operation[] opHandles = new TF_Operation[inputs.length];

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/Operation.java

@@ -25,16 +25,24 @@
  */
 public interface Operation {
 
-  /** Returns the full name of the Operation. */
+  /**
+   * Returns the full name of the Operation.
+   */
   String name();
 
   /**
-   * Returns the type of the operation, i.e., the name of the computation performed by the
-   * operation.
+   * Returns the type of the operation, i.e., the name of the computation performed by the operation.
    */
   String type();
 
-  /** Returns the number of tensors produced by this operation. */
+  /**
+   * Returns the execution environment this operation was created in.
+   */
+  ExecutionEnvironment env();
+
+  /**
+   * Returns the number of tensors produced by this operation.
+   */
   int numOutputs();
 
   /**

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/op/Op.java

@@ -15,6 +15,7 @@
 
 package org.tensorflow.op;
 
+import org.tensorflow.ExecutionEnvironment;
 import org.tensorflow.Operation;
 
 /**
@@ -48,4 +49,11 @@ public interface Op {
    * @return an {@link Operation}
    */
   Operation op();
+
+  /**
+   * Return the execution environment this op was created in.
+   */
+  default ExecutionEnvironment env() {
+    return op().env();
+  }
 }

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/op/Scope.java

@@ -16,14 +16,12 @@
 package org.tensorflow.op;
 
 import java.util.ArrayList;
-
 import org.tensorflow.DeviceSpec;
 import org.tensorflow.ExecutionEnvironment;
 import org.tensorflow.OperationBuilder;
 
 /**
- * Manages groups of related properties when creating Tensorflow Operations, such as a common name
- * prefix.
+ * Manages groups of related properties when creating Tensorflow Operations, such as a common name prefix.
  *
  * <p>A {@code Scope} is a container for common properties applied to TensorFlow Ops. Normal user
  * code initializes a {@code Scope} and provides it to Operation building classes. For example:
@@ -88,7 +86,9 @@ public Scope(ExecutionEnvironment env) {
     this(env, new NameScope(), new ArrayList<>(), DeviceSpec.newBuilder().build());
   }
 
-  /** Returns the execution environment used by this scope. */
+  /**
+   * Returns the execution environment used by this scope.
+   */
   public ExecutionEnvironment env() {
     return env;
   }
@@ -97,8 +97,7 @@ public ExecutionEnvironment env() {
    * Returns a new scope where added operations will have the provided name prefix.
    *
    * <p>Ops created with this scope will have {@code name/childScopeName/} as the prefix. The actual
-   * name will be unique in the returned scope. All other properties are inherited from the current
-   * scope.
+   * name will be unique in the returned scope. All other properties are inherited from the current scope.
    *
    * <p>The child scope name must match the regular expression {@code [A-Za-z0-9.][A-Za-z0-9_.\-]*}
    *
@@ -129,7 +128,8 @@ public Scope withName(String opName) {
   /**
    * Return a new scope that uses the provided device specification for an op.
    *
-   * <p>Operations created within this scope will place the created operations on the device(s) matching the provided spec.
+   * <p>Operations created within this scope will place the created operations on the device(s) matching the provided
+   * spec.
    *
    * @param deviceSpec device specification for an operator in the returned scope
    * @return a new Scope that uses opName for operations.
@@ -151,8 +151,8 @@ public Scope withDevice(DeviceSpec deviceSpec) {
    * }</pre>
    *
    * <p><b>Note:</b> if you provide a composite operator building class (i.e, a class that creates a
-   * set of related operations by calling other operator building code), the provided name will act
-   * as a subscope to all underlying operators.
+   * set of related operations by calling other operator building code), the provided name will act as a subscope to all
+   * underlying operators.
    *
    * @param defaultName name for the underlying operator.
    * @return unique name for the operator.
@@ -180,11 +180,15 @@ private Scope(
    * @return a new scope with the provided control dependencies
    */
   public Scope withControlDependencies(Iterable<Op> controls) {
+    for (Op control : controls) {
+      env.checkInput(control);
+    }
     return new Scope(env, nameScope, controls, deviceSpec);
   }
 
   /**
-   * Applies device specification and adds each Operand in controlDependencies as a control input to the provided builder.
+   * Applies device specification and adds each Operand in controlDependencies as a control input to the provided
+   * builder.
    *
    * @param builder OperationBuilder to add control inputs and device specification to
    */
@@ -210,7 +214,9 @@ public OperationBuilder applyControlDependencies(OperationBuilder builder) {
   private final NameScope nameScope;
   private final DeviceSpec deviceSpec;
 
-  /** Returns device string from the scope. */
+  /**
+   * Returns device string from the scope.
+   */
   public String getDeviceString() {
     return deviceSpec.toString();
   }

tensorflow-core/tensorflow-core-api/src/test/java/org/tensorflow/GraphOperationBuilderTest.java

@@ -23,30 +23,13 @@
 import org.tensorflow.exceptions.TFInvalidArgumentException;
 import org.tensorflow.ndarray.Shape;
 import org.tensorflow.op.Ops;
-import org.tensorflow.op.core.Constant;
 import org.tensorflow.proto.framework.DataType;
 import org.tensorflow.types.TBool;
 import org.tensorflow.types.TInt32;
 
 /** Unit tests for {@link org.tensorflow.GraphOperationBuilder}. */
 public class GraphOperationBuilderTest {
 
-  @Test
-  public void failWhenMixingOperationsOnDifferentGraphs() {
-    try (Graph g1 = new Graph();
-        Graph g2 = new Graph()) {
-      Ops tf = Ops.create(g1);
-      Constant<TInt32> c1 = tf.constant(3);
-      tf.math.add(c1, c1);
-      try {
-        Ops tf2 = Ops.create(g2);
-        tf2.math.add(c1, c1);
-      } catch (Exception e) {
-        fail(e.toString());
-      }
-    }
-  }
-
   @Test
   public void failOnUseAfterBuild() {
     try (Graph g = new Graph();