diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py index 20daf724c12..c0178f11647 100644 --- a/Lib/unittest/mock.py +++ b/Lib/unittest/mock.py @@ -1241,11 +1241,6 @@ def _importer(target): return thing -def _is_started(patcher): - # XXXX horrible - return hasattr(patcher, 'is_local') - - class _patch(object): attribute_name = None @@ -1316,14 +1311,9 @@ class _patch(object): @contextlib.contextmanager def decoration_helper(self, patched, args, keywargs): extra_args = [] - entered_patchers = [] - patching = None - - exc_info = tuple() - try: + with contextlib.ExitStack() as exit_stack: for patching in patched.patchings: - arg = patching.__enter__() - entered_patchers.append(patching) + arg = exit_stack.enter_context(patching) if patching.attribute_name is not None: keywargs.update(arg) elif patching.new is DEFAULT: @@ -1331,19 +1321,6 @@ class _patch(object): args += tuple(extra_args) yield (args, keywargs) - except: - if (patching not in entered_patchers and - _is_started(patching)): - # the patcher may have been started, but an exception - # raised whilst entering one of its additional_patchers - entered_patchers.append(patching) - # Pass the exception to __exit__ - exc_info = sys.exc_info() - # re-raise the exception - raise - finally: - for patching in reversed(entered_patchers): - patching.__exit__(*exc_info) def decorate_callable(self, func): @@ -1520,25 +1497,26 @@ class _patch(object): self.temp_original = original self.is_local = local - setattr(self.target, self.attribute, new_attr) - if self.attribute_name is not None: - extra_args = {} - if self.new is DEFAULT: - extra_args[self.attribute_name] = new - for patching in self.additional_patchers: - arg = patching.__enter__() - if patching.new is DEFAULT: - extra_args.update(arg) - return extra_args - - return new + self._exit_stack = contextlib.ExitStack() + try: + setattr(self.target, self.attribute, new_attr) + if self.attribute_name is not None: + extra_args = {} + if self.new is DEFAULT: + extra_args[self.attribute_name] = new + for patching in self.additional_patchers: + arg = self._exit_stack.enter_context(patching) + if patching.new is DEFAULT: + extra_args.update(arg) + return extra_args + return new + except: + if not self.__exit__(*sys.exc_info()): + raise def __exit__(self, *exc_info): """Undo the patch.""" - if not _is_started(self): - return - if self.is_local and self.temp_original is not DEFAULT: setattr(self.target, self.attribute, self.temp_original) else: @@ -1553,9 +1531,9 @@ class _patch(object): del self.temp_original del self.is_local del self.target - for patcher in reversed(self.additional_patchers): - if _is_started(patcher): - patcher.__exit__(*exc_info) + exit_stack = self._exit_stack + del self._exit_stack + return exit_stack.__exit__(*exc_info) def start(self): @@ -1571,9 +1549,9 @@ class _patch(object): self._active_patches.remove(self) except ValueError: # If the patch hasn't been started this will fail - pass + return None - return self.__exit__() + return self.__exit__(None, None, None) @@ -1873,9 +1851,9 @@ class _patch_dict(object): _patch._active_patches.remove(self) except ValueError: # If the patch hasn't been started this will fail - pass + return None - return self.__exit__() + return self.__exit__(None, None, None) def _clear_dict(in_dict): diff --git a/Lib/unittest/test/testmock/testpatch.py b/Lib/unittest/test/testmock/testpatch.py index f1bc0e1cd40..d8c1515f834 100644 --- a/Lib/unittest/test/testmock/testpatch.py +++ b/Lib/unittest/test/testmock/testpatch.py @@ -774,7 +774,7 @@ class PatchTest(unittest.TestCase): d = {'foo': 'bar'} original = d.copy() patcher = patch.dict(d, [('spam', 'eggs')], clear=True) - self.assertEqual(patcher.stop(), False) + self.assertFalse(patcher.stop()) self.assertEqual(d, original) diff --git a/Misc/NEWS.d/next/Library/2020-04-04-00-47-40.bpo-40126.Y-bTNP.rst b/Misc/NEWS.d/next/Library/2020-04-04-00-47-40.bpo-40126.Y-bTNP.rst new file mode 100644 index 00000000000..8f725cfba86 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-04-04-00-47-40.bpo-40126.Y-bTNP.rst @@ -0,0 +1,3 @@ +Fixed reverting multiple patches in unittest.mock. Patcher's ``__exit__()`` +is now never called if its ``__enter__()`` is failed. Returning true from +``__exit__()`` silences now the exception.