Make `TempFileCleanup.SUCCESS` work with Python 3.11 after https://github.com/python/cpython/pull/28180.

After the change, the errors from the test case were no longer buffered in `_Outcome`. Instead, we need to take a note of errors on the `TestResult` before, then compare errors after.

PiperOrigin-RevId: 461070558
Change-Id: I7d9f769cd46143a886bc5edeb224804acd8dbaf9

4 files changed, 70 insertions, 12 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3c36751..d083f61 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com).
 
 ## Unreleased
 
-Nothing notable unreleased.
+### Fixed
+
+*   Fixed a crash in Python 3.11 when `TempFileCleanup.SUCCESS` is used.
 
 ## 1.1.0 (2022-06-01)
 
diff --git a/absl/testing/absltest.py b/absl/testing/absltest.py
index d3cf95a..b7a941b 100644
--- a/absl/testing/absltest.py
+++ b/absl/testing/absltest.py
@@ -787,24 +787,49 @@ class TestCase(unittest.TestCase):
     elif cleanup == TempFileCleanup.ALWAYS:
       self.addCleanup(_rmtree_ignore_errors, path)
     elif cleanup == TempFileCleanup.SUCCESS:
-      self._internal_cleanup_on_success(_rmtree_ignore_errors, path)
+      self._internal_add_cleanup_on_success(_rmtree_ignore_errors, path)
     else:
       raise AssertionError('Unexpected cleanup value: {}'.format(cleanup))
 
-  def _internal_cleanup_on_success(self, function, *args, **kwargs):
-    # type: (Callable[..., object], Any, Any) -> None
+  def _internal_add_cleanup_on_success(
+      self,
+      function: Callable[..., Any],
+      *args: Any,
+      **kwargs: Any,
+  ) -> None:
+    """Adds `function` as cleanup when the test case succeeds."""
+    outcome = self._outcome
+    previous_failure_count = (
+        len(outcome.result.failures)
+        + len(outcome.result.errors)
+        + len(outcome.result.unexpectedSuccesses)
+    )
     def _call_cleaner_on_success(*args, **kwargs):
-      if not self._ran_and_passed():
+      if not self._internal_ran_and_passed_when_called_during_cleanup(
+          previous_failure_count):
         return
       function(*args, **kwargs)
     self.addCleanup(_call_cleaner_on_success, *args, **kwargs)
 
-  def _ran_and_passed(self):
-    # type: () -> bool
+  def _internal_ran_and_passed_when_called_during_cleanup(
+      self,
+      previous_failure_count: int,
+  ) -> bool:
+    """Returns whether test is passed. Expected to be called during cleanup."""
     outcome = self._outcome
-    result = self.defaultTestResult()
-    self._feedErrorsToResult(result, outcome.errors)  # pytype: disable=attribute-error
-    return result.wasSuccessful()
+    if sys.version_info[:2] >= (3, 11):
+      current_failure_count = (
+          len(outcome.result.failures)
+          + len(outcome.result.errors)
+          + len(outcome.result.unexpectedSuccesses)
+      )
+      return current_failure_count == previous_failure_count
+    else:
+      # Before Python 3.11 https://github.com/python/cpython/pull/28180, errors
+      # were bufferred in _Outcome before calling cleanup.
+      result = self.defaultTestResult()
+      self._feedErrorsToResult(result, outcome.errors)  # pytype: disable=attribute-error
+      return result.wasSuccessful()
 
   def shortDescription(self):
     # type: () -> Text
diff --git a/absl/testing/tests/absltest_test.py b/absl/testing/tests/absltest_test.py
index d941e07..43201bd 100644
--- a/absl/testing/tests/absltest_test.py
+++ b/absl/testing/tests/absltest_test.py
@@ -2145,6 +2145,11 @@ class TempFileTest(absltest.TestCase, HelperMixin):
         'TempFileHelperTest/test_failure',
         'TempFileHelperTest/test_failure/failure',
         'TempFileHelperTest/test_success',
+        'TempFileHelperTest/test_subtest_failure',
+        'TempFileHelperTest/test_subtest_failure/parent',
+        'TempFileHelperTest/test_subtest_failure/successful_child',
+        'TempFileHelperTest/test_subtest_failure/failed_child',
+        'TempFileHelperTest/test_subtest_success',
     }
     self.run_tempfile_helper('SUCCESS', expected)
 
@@ -2153,6 +2158,8 @@ class TempFileTest(absltest.TestCase, HelperMixin):
         'TempFileHelperTest',
         'TempFileHelperTest/test_failure',
         'TempFileHelperTest/test_success',
+        'TempFileHelperTest/test_subtest_failure',
+        'TempFileHelperTest/test_subtest_success',
     }
     self.run_tempfile_helper('ALWAYS', expected)
 
@@ -2163,6 +2170,14 @@ class TempFileTest(absltest.TestCase, HelperMixin):
         'TempFileHelperTest/test_failure/failure',
         'TempFileHelperTest/test_success',
         'TempFileHelperTest/test_success/success',
+        'TempFileHelperTest/test_subtest_failure',
+        'TempFileHelperTest/test_subtest_failure/parent',
+        'TempFileHelperTest/test_subtest_failure/successful_child',
+        'TempFileHelperTest/test_subtest_failure/failed_child',
+        'TempFileHelperTest/test_subtest_success',
+        'TempFileHelperTest/test_subtest_success/parent',
+        'TempFileHelperTest/test_subtest_success/child0',
+        'TempFileHelperTest/test_subtest_success/child1',
     }
     self.run_tempfile_helper('OFF', expected)
 
@@ -2172,8 +2187,8 @@ class SkipClassTest(absltest.TestCase):
   def test_incorrect_decorator_call(self):
     with self.assertRaises(TypeError):
 
-      @absltest.skipThisClass  # pylint: disable=unused-variable
-      class Test(absltest.TestCase):
+      @absltest.skipThisClass
+      class Test(absltest.TestCase):  # pylint: disable=unused-variable
         pass
 
   def test_incorrect_decorator_subclass(self):
diff --git a/absl/testing/tests/absltest_test_helper.py b/absl/testing/tests/absltest_test_helper.py
index e81a89b..89b6721 100644
--- a/absl/testing/tests/absltest_test_helper.py
+++ b/absl/testing/tests/absltest_test_helper.py
@@ -106,6 +106,8 @@ class HelperTest(absltest.TestCase):
 
 
 class TempFileHelperTest(absltest.TestCase):
+  """Helper test case for tempfile cleanup tests."""
+
   tempfile_cleanup = absltest.TempFileCleanup[os.environ.get(
       'ABSLTEST_TEST_HELPER_TEMPFILE_CLEANUP', 'SUCCESS')]
 
@@ -116,6 +118,20 @@ class TempFileHelperTest(absltest.TestCase):
   def test_success(self):
     self.create_tempfile('success')
 
+  def test_subtest_failure(self):
+    self.create_tempfile('parent')
+    with self.subTest('success'):
+      self.create_tempfile('successful_child')
+    with self.subTest('failure'):
+      self.create_tempfile('failed_child')
+      self.fail('expected failure')
+
+  def test_subtest_success(self):
+    self.create_tempfile('parent')
+    for i in range(2):
+      with self.subTest(f'success{i}'):
+        self.create_tempfile(f'child{i}')
+
 
 def main(argv):
   del argv  # Unused.