diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py
index 7bd11c8e703..0cd7af65b94 100644
--- a/Lib/unittest/mock.py
+++ b/Lib/unittest/mock.py
@@ -939,8 +939,8 @@ class NonCallableMock(Base):
                                     for e in expected])
                 raise AssertionError(
                     f'{problem}\n'
-                    f'Expected: {_CallList(calls)}\n'
-                    f'Actual: {self._calls_repr(prefix="Actual")}'
+                    f'Expected: {_CallList(calls)}'
+                    f'{self._calls_repr(prefix="Actual").rstrip(".")}'
                 ) from cause
             return
 
diff --git a/Lib/unittest/test/testmock/testasync.py b/Lib/unittest/test/testmock/testasync.py
index f951526dbeb..fde1e4a690b 100644
--- a/Lib/unittest/test/testmock/testasync.py
+++ b/Lib/unittest/test/testmock/testasync.py
@@ -892,21 +892,28 @@ class AsyncMockAssert(unittest.TestCase):
             self.mock.assert_not_awaited()
 
     def test_assert_has_awaits_not_matching_spec_error(self):
-        async def f(): pass
+        async def f(x=None): pass
 
-        mock = AsyncMock(spec=f)
+        self.mock = AsyncMock(spec=f)
+        asyncio.run(self._runnable_test(1))
 
         with self.assertRaisesRegex(
                 AssertionError,
-                re.escape('Awaits not found.\nExpected:')) as cm:
-            mock.assert_has_awaits([call()])
+                '^{}$'.format(
+                    re.escape('Awaits not found.\n'
+                              'Expected: [call()]\n'
+                              'Actual: [call(1)]'))) as cm:
+            self.mock.assert_has_awaits([call()])
         self.assertIsNone(cm.exception.__cause__)
 
         with self.assertRaisesRegex(
                 AssertionError,
-                re.escape('Error processing expected awaits.\n'
-                          "Errors: [None, TypeError('too many positional "
-                          "arguments')]\n"
-                          'Expected:')) as cm:
-            mock.assert_has_awaits([call(), call('wrong')])
+                '^{}$'.format(
+                    re.escape(
+                        'Error processing expected awaits.\n'
+                        "Errors: [None, TypeError('too many positional "
+                        "arguments')]\n"
+                        'Expected: [call(), call(1, 2)]\n'
+                        'Actual: [call(1)]'))) as cm:
+            self.mock.assert_has_awaits([call(), call(1, 2)])
         self.assertIsInstance(cm.exception.__cause__, TypeError)
diff --git a/Lib/unittest/test/testmock/testmock.py b/Lib/unittest/test/testmock/testmock.py
index 88807d71ccb..01bc4794446 100644
--- a/Lib/unittest/test/testmock/testmock.py
+++ b/Lib/unittest/test/testmock/testmock.py
@@ -1436,23 +1436,30 @@ class MockTest(unittest.TestCase):
         mock.assert_has_calls(calls[:-1], any_order=True)
 
     def test_assert_has_calls_not_matching_spec_error(self):
-        def f(): pass
+        def f(x=None): pass
 
         mock = Mock(spec=f)
+        mock(1)
 
         with self.assertRaisesRegex(
                 AssertionError,
-                re.escape('Calls not found.\nExpected:')) as cm:
+                '^{}$'.format(
+                    re.escape('Calls not found.\n'
+                              'Expected: [call()]\n'
+                              'Actual: [call(1)]'))) as cm:
             mock.assert_has_calls([call()])
         self.assertIsNone(cm.exception.__cause__)
 
+
         with self.assertRaisesRegex(
                 AssertionError,
-                re.escape('Error processing expected calls.\n'
-                          "Errors: [None, TypeError('too many positional "
-                          "arguments')]\n"
-                          'Expected:')) as cm:
-            mock.assert_has_calls([call(), call('wrong')])
+                '^{}$'.format(
+                    re.escape(
+                        'Error processing expected calls.\n'
+                        "Errors: [None, TypeError('too many positional arguments')]\n"
+                        "Expected: [call(), call(1, 2)]\n"
+                        'Actual: [call(1)]'))) as cm:
+            mock.assert_has_calls([call(), call(1, 2)])
         self.assertIsInstance(cm.exception.__cause__, TypeError)
 
     def test_assert_any_call(self):