bpo-37555: Update _CallList.__contains__ to respect ANY (#14700)

* Flip equality to use mock calls' __eq__

* bpo-37555: Regression test demonstrating assert_has_calls not working with ANY and spec_set

Co-authored-by: Neal Finne <neal@nealfinne.com>

* Revert "Flip equality to use mock calls' __eq__"

This reverts commit 94ddf54.

* bpo-37555: Add regression tests for mock ANY ordering issues

Add regression tests for whether __eq__ is order agnostic on _Call and _CallList, which is useful for comparisons involving ANY, especially if the ANY comparison is to a class not defaulting __eq__ to NotImplemented.

Co-authored-by: Neal Finne <neal@nealfinne.com>

* bpo-37555: Fix _CallList and _Call order sensitivity

_Call and _CallList depend on ordering to correctly process that an object being compared to ANY with __eq__ should return True. This fix updates the comparison to check both a == b and b == a and return True if either condition is met, fixing situations from the tests in the previous two commits where assertEqual would not be commutative if checking _Call or _CallList objects. This seems like a reasonable fix considering that the Python data model specifies that if an object doesn't know how to compare itself to another object it should return NotImplemented, and that on getting NotImplemented from a == b, it should try b == a, implying that good behavior for __eq__ is commutative. This also flips the order of comparison in _CallList's __contains__ method, guaranteeing ANY will be on the left and have it's __eq__ called for equality checking, fixing the interaction between assert_has_calls and ANY.

Co-author: Neal Finne <neal@neal.finne.com>

* bpo-37555: Ensure _call_matcher returns _Call object

* Adding ACK and news entry

* bpo-37555: Replacing __eq__ with == to sidestep NotImplemented

bool(NotImplemented) returns True, so it's necessary to use ==
instead of __eq__ in this comparison.

* bpo-37555: cleaning up changes unnecessary to the final product

* bpo-37555: Fixed call on bound arguments to respect args and kwargs

* Revert "bpo-37555: Add regression tests for mock ANY ordering issues"

This reverts commit 49c5310.

* Revert "bpo-37555: cleaning up changes unnecessary to the final product"

This reverts commit 18e964b.

* Revert "bpo-37555: Replacing __eq__ with == to sidestep NotImplemented"

This reverts commit f295eac.

* Revert "bpo-37555: Fix _CallList and _Call order sensitivity"

This reverts commit 874fb69.

* Updated NEWS.d

* bpo-37555: Add tests checking every function using _call_matcher both with and without spec

* bpo-37555: Ensure all assert methods using _call_matcher are actually passing calls

* Remove AnyCompare and use call objects everywhere.

* Revert "Remove AnyCompare and use call objects everywhere."

This reverts commit 24973c0.

* Check for exception in assert_any_await

Author: ElizabethU

Lib/unittest/mock.py

@@ -852,7 +852,8 @@ def _call_matcher(self, _call):
             else:
                 name, args, kwargs = _call
             try:
-                return name, sig.bind(*args, **kwargs)
+                bound_call = sig.bind(*args, **kwargs)
+                return call(name, bound_call.args, bound_call.kwargs)
             except TypeError as e:
                 return e.with_traceback(None)
         else:
@@ -901,9 +902,9 @@ def assert_called_with(self, /, *args, **kwargs):
         def _error_message():
             msg = self._format_mock_failure_message(args, kwargs)
             return msg
-        expected = self._call_matcher((args, kwargs))
+        expected = self._call_matcher(_Call((args, kwargs), two=True))
         actual = self._call_matcher(self.call_args)
-        if expected != actual:
+        if actual != expected:
             cause = expected if isinstance(expected, Exception) else None
             raise AssertionError(_error_message()) from cause
 
@@ -963,10 +964,10 @@ def assert_any_call(self, /, *args, **kwargs):
         The assert passes if the mock has *ever* been called, unlike
         `assert_called_with` and `assert_called_once_with` that only pass if
         the call is the most recent one."""
-        expected = self._call_matcher((args, kwargs))
+        expected = self._call_matcher(_Call((args, kwargs), two=True))
+        cause = expected if isinstance(expected, Exception) else None
         actual = [self._call_matcher(c) for c in self.call_args_list]
-        if expected not in actual:
-            cause = expected if isinstance(expected, Exception) else None
+        if cause or expected not in _AnyComparer(actual):
             expected_string = self._format_mock_call_signature(args, kwargs)
             raise AssertionError(
                 '%s call not found' % expected_string
@@ -1019,6 +1020,22 @@ def _calls_repr(self, prefix="Calls"):
         return f"\n{prefix}: {safe_repr(self.mock_calls)}."
 
 
+class _AnyComparer(list):
+    """A list which checks if it contains a call which may have an
+    argument of ANY, flipping the components of item and self from
+    their traditional locations so that ANY is guaranteed to be on
+    the left."""
+    def __contains__(self, item):
+        for _call in self:
+            if len(item) != len(_call):
+                continue
+            if all([
+                expected == actual
+                for expected, actual in zip(item, _call)
+            ]):
+                return True
+        return False
+
 
 def _try_iter(obj):
     if obj is None:
@@ -2171,9 +2188,9 @@ def _error_message():
             msg = self._format_mock_failure_message(args, kwargs, action='await')
             return msg
 
-        expected = self._call_matcher((args, kwargs))
+        expected = self._call_matcher(_Call((args, kwargs), two=True))
         actual = self._call_matcher(self.await_args)
-        if expected != actual:
+        if actual != expected:
             cause = expected if isinstance(expected, Exception) else None
             raise AssertionError(_error_message()) from cause
 
@@ -2192,10 +2209,10 @@ def assert_any_await(self, /, *args, **kwargs):
         """
         Assert the mock has ever been awaited with the specified arguments.
         """
-        expected = self._call_matcher((args, kwargs))
+        expected = self._call_matcher(_Call((args, kwargs), two=True))
+        cause = expected if isinstance(expected, Exception) else None
         actual = [self._call_matcher(c) for c in self.await_args_list]
-        if expected not in actual:
-            cause = expected if isinstance(expected, Exception) else None
+        if cause or expected not in _AnyComparer(actual):
             expected_string = self._format_mock_call_signature(args, kwargs)
             raise AssertionError(
                 '%s await not found' % expected_string

Lib/unittest/test/testmock/testasync.py

@@ -2,8 +2,8 @@
 import inspect
 import unittest
 
-from unittest.mock import (call, AsyncMock, patch, MagicMock, create_autospec,
-                           _AwaitEvent)
+from unittest.mock import (ANY, call, AsyncMock, patch, MagicMock,
+                           create_autospec, _AwaitEvent)
 
 
 def tearDownModule():
@@ -192,6 +192,10 @@ async def main():
         spec.assert_awaited_with(1, 2, c=3)
         spec.assert_awaited()
 
+        with self.assertRaises(AssertionError):
+            spec.assert_any_await(e=1)
+
+
     def test_patch_with_autospec(self):
 
         async def test_async():
@@ -607,6 +611,30 @@ def test_assert_has_awaits_no_order(self):
         asyncio.run(self._runnable_test('SomethingElse'))
         self.mock.assert_has_awaits(calls)
 
+    def test_awaits_asserts_with_any(self):
+        class Foo:
+            def __eq__(self, other): pass
+
+        asyncio.run(self._runnable_test(Foo(), 1))
+
+        self.mock.assert_has_awaits([call(ANY, 1)])
+        self.mock.assert_awaited_with(ANY, 1)
+        self.mock.assert_any_await(ANY, 1)
+
+    def test_awaits_asserts_with_spec_and_any(self):
+        class Foo:
+            def __eq__(self, other): pass
+
+        mock_with_spec = AsyncMock(spec=Foo)
+
+        async def _custom_mock_runnable_test(*args):
+            await mock_with_spec(*args)
+
+        asyncio.run(_custom_mock_runnable_test(Foo(), 1))
+        mock_with_spec.assert_has_awaits([call(ANY, 1)])
+        mock_with_spec.assert_awaited_with(ANY, 1)
+        mock_with_spec.assert_any_await(ANY, 1)
+
     def test_assert_has_awaits_ordered(self):
         calls = [call('NormalFoo'), call('baz')]
         with self.assertRaises(AssertionError):

Lib/unittest/test/testmock/testhelpers.py

@@ -64,7 +64,28 @@ def __ne__(self, other): pass
             self.assertEqual(expected, mock.mock_calls)
             self.assertEqual(mock.mock_calls, expected)
 
+    def test_any_no_spec(self):
+        # This is a regression test for bpo-37555
+        class Foo:
+            def __eq__(self, other): pass
+
+        mock = Mock()
+        mock(Foo(), 1)
+        mock.assert_has_calls([call(ANY, 1)])
+        mock.assert_called_with(ANY, 1)
+        mock.assert_any_call(ANY, 1)
+
+    def test_any_and_spec_set(self):
+        # This is a regression test for bpo-37555
+        class Foo:
+            def __eq__(self, other): pass
+
+        mock = Mock(spec=Foo)
 
+        mock(Foo(), 1)
+        mock.assert_has_calls([call(ANY, 1)])
+        mock.assert_called_with(ANY, 1)
+        mock.assert_any_call(ANY, 1)
 
 class CallTest(unittest.TestCase):
 

Misc/ACKS

@@ -503,6 +503,7 @@ Tomer Filiba
 Segev Finer
 Jeffrey Finkelstein
 Russell Finn
+Neal Finne
 Dan Finnie
 Nils Fischbeck
 Frederik Fix
@@ -1714,6 +1715,7 @@ Roger Upole
 Daniel Urban
 Michael Urman
 Hector Urtubia
+Elizabeth Uselton
 Lukas Vacek
 Ville Vainio
 Yann Vaginay

Misc/NEWS.d/next/Library/2019-07-19-20-13-48.bpo-37555.S5am28.rst

@@ -0,0 +1,2 @@
+Fix `NonCallableMock._call_matcher` returning tuple instead of `_Call` object
+when `self._spec_signature` exists. Patch by Elizabeth Uselton