Fix missing case for detecting future imports

PiperOrigin-RevId: 239268639

tensorflow/python/autograph/pyct/inspect_utils.py

@@ -298,7 +298,7 @@ def getfutureimports(entity):
   Returns:
     A tuple of future strings
   """
-  if not tf_inspect.isfunction(entity):
+  if not (tf_inspect.isfunction(entity) or tf_inspect.ismethod(entity)):
     return tuple()
   return tuple(sorted(name for name, value in entity.__globals__.items()
                       if getattr(value, '__module__', None) == '__future__'))

tensorflow/python/autograph/pyct/inspect_utils_test.py

@@ -415,12 +415,18 @@ class InspectUtilsTest(test.TestCase):
     self.assertTrue(inspect_utils.isbuiltin(zip))
     self.assertFalse(inspect_utils.isbuiltin(function_decorator))
 
-  def test_getfutureimports_simple_case(self):
+  def test_getfutureimports_functions(self):
     expected_imports = ('absolute_import', 'division', 'print_function',
                         'with_statement')
     self.assertEqual(inspect_utils.getfutureimports(future_import_module.f),
                      expected_imports)
 
+  def test_getfutureimports_methods(self):
+    expected_imports = ('absolute_import', 'division', 'print_function',
+                        'with_statement')
+    self.assertEqual(inspect_utils.getfutureimports(future_import_module.Foo.f),
+                     expected_imports)
+
   def test_super_wrapper_for_dynamic_attrs(self):
 
     a = object()

tensorflow/python/autograph/pyct/testing/future_import_module.py

@@ -24,3 +24,9 @@ from __future__ import with_statement
 
 def f():
   print('foo')
+
+
+class Foo(object):
+
+  def f(self):
+    print('foo')