Closes #21256: Printout of keyword args in deterministic order in mock calls.

Printout of keyword args should be in deterministic order in
a mock function call. This will help to write better doctests.

2 files changed, 7 insertions, 1 deletions

diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py
index d9c2ee9..d001976 100644
--- a/Lib/unittest/mock.py
+++ b/Lib/unittest/mock.py
@@ -1894,7 +1894,7 @@ def _format_call_signature(name, args, kwargs):
     formatted_args = ''
     args_string = ', '.join([repr(arg) for arg in args])
     kwargs_string = ', '.join([
-        '%s=%r' % (key, value) for key, value in kwargs.items()
+        '%s=%r' % (key, value) for key, value in sorted(kwargs.items())
     ])
     if args_string:
         formatted_args = args_string
diff --git a/Lib/unittest/test/testmock/testmock.py b/Lib/unittest/test/testmock/testmock.py
index b65dc32..7019ee9 100644
--- a/Lib/unittest/test/testmock/testmock.py
+++ b/Lib/unittest/test/testmock/testmock.py
@@ -1206,6 +1206,12 @@ class MockTest(unittest.TestCase):
         with self.assertRaises(AssertionError):
             m.hello.assert_not_called()
 
+    #Issue21256 printout of keyword args should be in deterministic order
+    def test_sorted_call_signature(self):
+        m = Mock()
+        m.hello(name='hello', daddy='hero')
+        text = "call(daddy='hero', name='hello')"
+        self.assertEquals(repr(m.hello.call_args), text)
 
     def test_mock_add_spec(self):
         class _One(object):