Add bool support for Dimension.

PiperOrigin-RevId: 350393553
Change-Id: Ife4004b377cd9dfab1322a08d6e7c4e74fc5416c

tensorflow/python/framework/tensor_shape.py

@@ -234,6 +234,10 @@ class Dimension(object):
       return None
     return self._value != other.value
 
+  def __bool__(self):
+    """Equivalent to `bool(self.value)`."""
+    return bool(self._value)
+
   def __int__(self):
     return self._value
 

tensorflow/python/framework/tensor_shape_test.py

@@ -195,6 +195,14 @@ class DimensionTest(test_util.TensorFlowTestCase):
     with self.assertRaises(TypeError):
       tensor_shape.Dimension(dtypes.string)
 
+  def testBool(self):
+    one = tensor_shape.Dimension(1)
+    zero = tensor_shape.Dimension(0)
+    has_none = tensor_shape.Dimension(None)
+    self.assertTrue(one)
+    self.assertFalse(zero)
+    self.assertFalse(has_none)
+
   def testMod(self):
     four = tensor_shape.Dimension(4)
     nine = tensor_shape.Dimension(9)