Clarifies meaning of is_tensor in the documentation.

Also clarifies documentation of TensorLike. Makes RaggedTensor subclass TensorLike.
Also renames _TensorLike to TensorLike since we expect more usages of it.

PiperOrigin-RevId: 303357719
Change-Id: Ieea5b0941e2149e2ad4670e449c72c471685cf37

tensorflow/python/autograph/operators/control_flow.py

@@ -340,11 +340,8 @@ def for_stmt(iter_, extra_test, body, get_state, set_state, symbol_names, opts):
   """
   if tensor_util.is_tensor(iter_):
     if tensors.is_range_tensor(iter_):
-      _tf_range_for_stmt(iter_, extra_test, body, get_state, set_state,
-                         symbol_names, opts)
-    elif isinstance(iter_, ragged_tensor.RaggedTensor):
-      _tf_ragged_for_stmt(iter_, extra_test, body, get_state, set_state,
-                          symbol_names, opts)
+      _tf_range_for_stmt(
+          iter_, extra_test, body, get_state, set_state, symbol_names, opts)
     else:
       _known_len_tf_for_stmt(
           iter_, extra_test, body, get_state, set_state, symbol_names, opts)

tensorflow/python/data/kernel_tests/memory_cleanup_test.py

@@ -116,7 +116,7 @@ class MemoryCleanupTest(test_base.DatasetTestBase, parameterized.TestCase):
 
     gc.collect()
     tensors = [
-        o for o in gc.get_objects() if isinstance(o, tensor_like.TensorLike)
+        o for o in gc.get_objects() if isinstance(o, tensor_like._TensorLike)
     ]
     self.assertEmpty(tensors, "%d Tensors are still alive." % len(tensors))
 

tensorflow/python/framework/indexed_slices.py

@@ -54,9 +54,13 @@ tensor_util = LazyLoader(
     "tensor_util", globals(),
     "tensorflow.python.framework.tensor_util")
 
+# pylint: disable=protected-access
+_TensorLike = tensor_like._TensorLike
+# pylint: enable=protected-access
+
 
 @tf_export("IndexedSlices")
-class IndexedSlices(tensor_like.TensorLike, composite_tensor.CompositeTensor):
+class IndexedSlices(_TensorLike, composite_tensor.CompositeTensor):
   """A sparse representation of a set of tensor slices at given indices.
 
   This class is a simple wrapper for a pair of `Tensor` objects:
@@ -305,7 +309,7 @@ def internal_convert_to_tensor_or_indexed_slices(value,
   """
   if isinstance(value, ops.EagerTensor) and not context.executing_eagerly():
     return ops.convert_to_tensor(value, dtype=dtype, name=name, as_ref=as_ref)
-  elif isinstance(value, tensor_like.TensorLike):
+  elif isinstance(value, _TensorLike):
     if dtype and not dtypes.as_dtype(dtype).is_compatible_with(value.dtype):
       raise ValueError(
           "Tensor conversion requested dtype %s for Tensor with dtype %s: %r" %

tensorflow/python/framework/ops.py

@@ -94,6 +94,7 @@ _api_usage_gauge = monitoring.BoolGauge(
 
 
 # pylint: disable=protected-access
+_TensorLike = tensor_like._TensorLike
 _DTYPES_INTERN_TABLE = dtypes._INTERN_TABLE
 # pylint: enable=protected-access
 
@@ -289,7 +290,7 @@ def disable_tensor_equality():
 
 
 @tf_export("Tensor")
-class Tensor(tensor_like.TensorLike):
+class Tensor(_TensorLike):
   """A tensor is a multidimensional array of elements represented by a
 
   `tf.Tensor` object.  All elements are of a single known data type.
@@ -5982,12 +5983,9 @@ def _assert_same_graph(original_item, item):
   Raises:
     ValueError: if graphs do not match.
   """
-  original_graph = getattr(original_item, "graph", None)
-  graph = getattr(item, "graph", None)
-  if original_graph and graph and original_graph is not graph:
-    raise ValueError(
-        "%s must be from the same graph as %s (graphs are %s and %s)." %
-        (item, original_item, graph, original_graph))
+  if original_item.graph is not item.graph:
+    raise ValueError("%s must be from the same graph as %s." %
+                     (item, original_item))
 
 
 def _get_graph_from_inputs(op_input_list, graph=None):
@@ -6041,16 +6039,16 @@ def _get_graph_from_inputs(op_input_list, graph=None):
     # TODO(josh11b): Note that we exclude subclasses of Tensor. Need to clean this
     # up.
     graph_element = None
-    if (isinstance(op_input, (Operation, tensor_like.TensorLike)) and
+    if (isinstance(op_input, (Operation, _TensorLike)) and
         ((not isinstance(op_input, Tensor)) or type(op_input) == Tensor)):  # pylint: disable=unidiomatic-typecheck
       graph_element = op_input
-    elif isinstance(op_input, Tensor):
+    else:
       graph_element = _as_graph_element(op_input)
 
     if graph_element is not None:
       if not graph:
         original_graph_element = graph_element
-        graph = getattr(graph_element, "graph", None)
+        graph = graph_element.graph
       elif original_graph_element is not None:
         _assert_same_graph(original_graph_element, graph_element)
       elif graph_element.graph is not graph:

tensorflow/python/framework/sparse_tensor.py

@@ -38,13 +38,14 @@ from tensorflow.python.ops import gen_sparse_ops
 from tensorflow.python.util.tf_export import tf_export
 
 # pylint: disable=protected-access
+_TensorLike = tensor_like._TensorLike
 _eval_using_default_session = ops._eval_using_default_session
 _override_helper = ops._override_helper
 # pylint: enable=protected-access
 
 
 @tf_export("sparse.SparseTensor", "SparseTensor")
-class SparseTensor(tensor_like.TensorLike, composite_tensor.CompositeTensor):
+class SparseTensor(_TensorLike, composite_tensor.CompositeTensor):
   """Represents a sparse tensor.
 
   TensorFlow represents a sparse tensor as three separate dense tensors:

tensorflow/python/framework/tensor_like.py

@@ -19,10 +19,7 @@ from __future__ import division
 from __future__ import print_function
 
 
-class TensorLike(object):
-  """TF-specific types TF operations are expected to natively support.
-
-  Do not check this with isinstance directly; prefer instead using
-  `tf.is_tensor` to check whether converting to a tensor is necessary.
-  """
+# NOTE(ebrevdo): Do not subclass this.  If you do, I will break you on purpose.
+class _TensorLike(object):
+  """Internal cls for grouping Tensor, SparseTensor, ..., for is_instance."""
   pass

tensorflow/python/framework/tensor_util.py

@@ -978,23 +978,17 @@ def constant_value_as_shape(tensor):  # pylint: disable=invalid-name
 
 @tf_export("is_tensor")
 def is_tensor(x):  # pylint: disable=invalid-name
-  """Checks whether `x` is a TF-native type that can be passed to many TF ops.
+  """Checks whether `x` is a tensor or "tensor-like".
 
-  Use is_tensor to differentiate types that can ingested by TensorFlow ops
-  without any conversion (e.g., `tf.Tensor`, `tf.SparseTensor`, and
-  `tf.RaggedTensor`) from types that need to be converted into tensors before
-  they are ingested (e.g., numpy `ndarray` and Python scalars).
+  If `is_tensor(x)` returns `True`, it is safe to assume that `x` is a tensor or
+  can be converted to a tensor using `ops.convert_to_tensor(x)`.
 
-  For example, in the following code block:
+  Usage example:
 
-  ```python
-  if not tf.is_tensor(t):
-    t = tf.convert_to_tensor(t)
-  return t.dtype
-  ```
-
-  we check to make sure that `t` is a tensor (and convert it if not) before
-  accessing its `shape` and `dtype`.
+  >>> tf.is_tensor(tf.constant([[1,2,3],[4,5,6],[7,8,9]]))
+  True
+  >>> tf.is_tensor("Hello World")
+  False
 
   Args:
     x: A python object to check.
@@ -1002,7 +996,8 @@ def is_tensor(x):  # pylint: disable=invalid-name
   Returns:
     `True` if `x` is a tensor or "tensor-like", `False` if not.
   """
-  return (isinstance(x, (tensor_like.TensorLike, core.Tensor)) or
+  # TODO(mdan): Remove these. Only keep core.Tensor.
+  return (isinstance(x, (tensor_like._TensorLike, core.Tensor)) or  # pylint: disable=protected-access
           ops.is_dense_tensor_like(x) or
           getattr(x, "is_tensor_like", False))
 

tensorflow/python/keras/engine/training_utils.py

@@ -56,7 +56,6 @@ from tensorflow.python.ops import array_ops
 from tensorflow.python.ops import gen_array_ops
 from tensorflow.python.ops import math_ops
 from tensorflow.python.ops.losses import util as tf_losses_utils
-from tensorflow.python.ops.ragged import ragged_tensor
 from tensorflow.python.platform import tf_logging as logging
 from tensorflow.python.util import nest
 from tensorflow.python.util import tf_inspect
@@ -1050,21 +1049,11 @@ def has_symbolic_tensors(ls):
 
 
 def has_tensors(ls):
-  """Returns true if `ls` contains tensors."""
-  # Note: at some point in time ragged tensors didn't count as tensors, so this
-  # returned false for ragged tensors. Making this return true fails some tests
-  # which would then require a steps_per_epoch argument.
   if isinstance(ls, (list, tuple)):
-    return any(
-        tensor_util.is_tensor(v) and
-        not isinstance(v, ragged_tensor.RaggedTensor) for v in ls)
+    return any(tensor_util.is_tensor(v) for v in ls)
   if isinstance(ls, dict):
-    return any(
-        tensor_util.is_tensor(v) and
-        not isinstance(v, ragged_tensor.RaggedTensor)
-        for _, v in six.iteritems(ls))
-  return tensor_util.is_tensor(ls) and not isinstance(
-      ls, ragged_tensor.RaggedTensor)
+    return any(tensor_util.is_tensor(v) for _, v in six.iteritems(ls))
+  return tensor_util.is_tensor(ls)
 
 
 def get_metric_name(metric, weighted=False):

tensorflow/python/ops/ragged/ragged_tensor.py

@@ -30,7 +30,6 @@ from tensorflow.python.framework import constant_op
 from tensorflow.python.framework import dtypes
 from tensorflow.python.framework import ops
 from tensorflow.python.framework import sparse_tensor
-from tensorflow.python.framework import tensor_like
 from tensorflow.python.framework import tensor_shape
 from tensorflow.python.framework import tensor_spec
 from tensorflow.python.framework import type_spec
@@ -55,7 +54,7 @@ _convert_row_partition = RowPartition._convert_row_partition
 
 
 @tf_export("RaggedTensor")
-class RaggedTensor(composite_tensor.CompositeTensor, tensor_like.TensorLike):
+class RaggedTensor(composite_tensor.CompositeTensor):
   """Represents a ragged tensor.
 
   A `RaggedTensor` is a tensor with one or more *ragged dimensions*, which are

tensorflow/tools/api/golden/v1/tensorflow.-indexed-slices.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.IndexedSlices"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.indexed_slices.IndexedSlices\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
   is_instance: "<type \'object\'>"
   member {

tensorflow/tools/api/golden/v1/tensorflow.-ragged-tensor.pbtxt

@@ -2,7 +2,6 @@ path: "tensorflow.RaggedTensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.ops.ragged.ragged_tensor.RaggedTensor\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
   is_instance: "<type \'object\'>"
   member {
     name: "dtype"

tensorflow/tools/api/golden/v1/tensorflow.-sparse-tensor.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.SparseTensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.sparse_tensor.SparseTensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
   is_instance: "<type \'object\'>"
   member {

tensorflow/tools/api/golden/v1/tensorflow.-tensor.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.Tensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.ops.Tensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<type \'object\'>"
   member {
     name: "OVERLOADABLE_OPERATORS"

tensorflow/tools/api/golden/v1/tensorflow.sparse.-sparse-tensor.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.sparse.SparseTensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.sparse_tensor.SparseTensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
   is_instance: "<type \'object\'>"
   member {

tensorflow/tools/api/golden/v2/tensorflow.-indexed-slices.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.IndexedSlices"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.indexed_slices.IndexedSlices\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
   is_instance: "<type \'object\'>"
   member {

tensorflow/tools/api/golden/v2/tensorflow.-ragged-tensor.pbtxt

@@ -2,7 +2,6 @@ path: "tensorflow.RaggedTensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.ops.ragged.ragged_tensor.RaggedTensor\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
   is_instance: "<type \'object\'>"
   member {
     name: "dtype"

tensorflow/tools/api/golden/v2/tensorflow.-sparse-tensor.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.SparseTensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.sparse_tensor.SparseTensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
   is_instance: "<type \'object\'>"
   member {

tensorflow/tools/api/golden/v2/tensorflow.-tensor.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.Tensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.ops.Tensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<type \'object\'>"
   member {
     name: "OVERLOADABLE_OPERATORS"

tensorflow/tools/api/golden/v2/tensorflow.sparse.-sparse-tensor.pbtxt

@@ -1,7 +1,7 @@
 path: "tensorflow.sparse.SparseTensor"
 tf_class {
   is_instance: "<class \'tensorflow.python.framework.sparse_tensor.SparseTensor\'>"
-  is_instance: "<class \'tensorflow.python.framework.tensor_like.TensorLike\'>"
+  is_instance: "<class \'tensorflow.python.framework.tensor_like._TensorLike\'>"
   is_instance: "<class \'tensorflow.python.framework.composite_tensor.CompositeTensor\'>"
   is_instance: "<type \'object\'>"
   member {