Merge changes from github.

Revert #18413. Too many internal test failures due to the name scope change caused by this change.
Revert #18192. Cannot use re2::StringPiece internally. Need alternative for set call. Will pull and clean this up in a separate change.

PiperOrigin-RevId: 197991247

2 files changed, 28 insertions, 2 deletions

diff --git a/tensorflow/python/layers/base.py b/tensorflow/python/layers/base.py
index 340c34fc5e..eda036ece4 100644
--- a/tensorflow/python/layers/base.py
+++ b/tensorflow/python/layers/base.py
@@ -191,6 +191,16 @@ class Layer(base_layer.Layer):
       RuntimeError: If called with partioned variable regularization and
         eager execution is enabled.
     """
+    
+    def _should_add_regularizer(variable, existing_variable_set):
+      if isinstance(variable, tf_variables.PartitionedVariable):
+        for var in variable:
+          if var in existing_variable_set:
+            return False
+        return True
+      else:
+        return variable not in existing_variable_set
+
     init_graph = None
     if not context.executing_eagerly():
       default_graph = ops.get_default_graph()
@@ -233,7 +243,8 @@ class Layer(base_layer.Layer):
             getter=vs.get_variable)
 
         if regularizer:
-          if context.executing_eagerly() or variable not in existing_variables:
+          if context.executing_eagerly() or _should_add_regularizer(
+              variable, existing_variables):
             self._handle_weight_regularization(name, variable, regularizer)
 
         if init_graph is not None:
@@ -353,4 +364,3 @@ def _add_elements_to_collection(elements, collection_list):
     for element in elements:
       if element not in collection_set:
         collection.append(element)
-
diff --git a/tensorflow/python/layers/base_test.py b/tensorflow/python/layers/base_test.py
index f08b552840..ab49e37b90 100644
--- a/tensorflow/python/layers/base_test.py
+++ b/tensorflow/python/layers/base_test.py
@@ -30,6 +30,7 @@ from tensorflow.python.layers import core as core_layers
 from tensorflow.python.ops import array_ops
 from tensorflow.python.ops import init_ops
 from tensorflow.python.ops import math_ops
+from tensorflow.python.ops import partitioned_variables
 from tensorflow.python.ops import random_ops
 from tensorflow.python.ops import state_ops
 from tensorflow.python.ops import variable_scope
@@ -95,6 +96,21 @@ class BaseLayerTest(test.TestCase):
           regularizer=regularizer)
       self.assertEqual(len(layer.losses), 1)
 
+  def testReusePartitionedVaraiblesAndRegularizers(self):
+    regularizer = lambda x: math_ops.reduce_sum(x) * 1e-3
+    partitioner = partitioned_variables.fixed_size_partitioner(3)
+    for reuse in [False, True]:
+      with variable_scope.variable_scope(variable_scope.get_variable_scope(),
+                                         partitioner=partitioner,
+                                         reuse=reuse):
+        layer = base_layers.Layer(name='my_layer')
+        variable = layer.add_variable(
+            'reg_part_var', [4, 4],
+            initializer=init_ops.zeros_initializer(),
+            regularizer=regularizer)
+    self.assertEqual(
+        len(ops.get_collection(ops.GraphKeys.REGULARIZATION_LOSSES)), 3)
+
   def testNoEagerActivityRegularizer(self):
     with context.eager_mode():
       with self.assertRaisesRegexp(ValueError, 'activity_regularizer'):