Skip to content

gh-108927: Fix removing testing modules from sys.modules #108952

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
20 commits
Select commit Hold shift + click to select a range
339f260
gh-108927: Do not remove tested modules from sys.modules
serhiy-storchaka Sep 5, 2023
e52be9b
Update NEWS entry.
serhiy-storchaka Sep 5, 2023
68c014e
Fix unloading the newly imported modules after testing.
serhiy-storchaka Sep 6, 2023
c1ad70c
Merge branch 'main' into regretest-no-remove-test-module
serhiy-storchaka Sep 12, 2023
3f25ab4
Add tests.
serhiy-storchaka Sep 12, 2023
7673248
Update Misc/NEWS.d/next/Tests/2023-09-05-20-46-35.gh-issue-108927.Tpw…
serhiy-storchaka Sep 12, 2023
5df4c8b
Move save/unload modules down in single.py.
serhiy-storchaka Sep 13, 2023
eb7766b
Merge branch 'main' into regretest-no-remove-test-module
serhiy-storchaka Sep 13, 2023
0eae535
Refactoring.
serhiy-storchaka Sep 13, 2023
66437b5
Remove also attributes from parent modules.
serhiy-storchaka Sep 13, 2023
8470b33
Merge branch 'main' into regretest-no-remove-test-module
serhiy-storchaka Oct 14, 2023
544c068
Merge branch 'main' into regretest-no-remove-test-module
serhiy-storchaka Nov 27, 2023
1e7ea34
Merge branch 'main' into regretest-no-remove-test-module
serhiy-storchaka Nov 28, 2023
56621ab
Only unload modules if run tests sequentially.
serhiy-storchaka Nov 28, 2023
ba5597a
Apply suggestions from code review
serhiy-storchaka Dec 1, 2023
d025e22
Merge branch 'main' into regretest-no-remove-test-module
serhiy-storchaka Dec 4, 2023
1aae341
Add a comment.
serhiy-storchaka Dec 4, 2023
017f01d
Test that test modules are really unloaded.
serhiy-storchaka Dec 4, 2023
5086405
Merge remote-tracking branch 'refs/remotes/origin/regretest-no-remove…
serhiy-storchaka Dec 4, 2023
b3ea8fa
Update Lib/test/test_regrtest.py
serhiy-storchaka Dec 4, 2023
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 13 additions & 5 deletions Lib/test/libregrtest/main.py
Original file line number Diff line number Diff line change
Expand Up @@ -311,7 +311,7 @@ def run_tests_sequentially(self, runtests) -> None:
else:
tracer = None

save_modules = sys.modules.keys()
save_modules = set(sys.modules)
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I would prefer to move this logic inside libregrtest/single.py, in the run_single_test() function.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I did it, but it is only needed in single-process run. In multi-process run it only adds an overhead. So I moved it back.


jobs = runtests.get_jobs()
if jobs is not None:
Expand All @@ -335,10 +335,18 @@ def run_tests_sequentially(self, runtests) -> None:

result = self.run_test(test_name, runtests, tracer)

# Unload the newly imported modules (best effort finalization)
for module in sys.modules.keys():
if module not in save_modules and module.startswith("test."):
support.unload(module)
# Unload the newly imported test modules (best effort finalization)
new_modules = [module for module in sys.modules
if module not in save_modules and
module.startswith(("test.", "test_"))]
for module in new_modules:
sys.modules.pop(module, None)
# Remove the attribute of the parent module.
parent, _, name = module.rpartition('.')
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Maybe raise an error if the parent itself has a parent other than test.. Currently, it should not happen. But it may happen in the future, if tests are reorganized.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

What do you mean? The parent should be "test" or start with "test.", because the module starts with "test.". If the parent starts with "test." it will be removed as well. If it was already removed before children, the code ignores KeyError.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

If a test imports test.test_a.test_b.test_c, does this code unloads test.test_a, test.test_a.test_b and test.test_a.test_b.test_c?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yes, if they were not imported before running tests.

try:
delattr(sys.modules[parent], name)
except (KeyError, AttributeError):
pass

if result.must_stop(self.fail_fast, self.fail_env_changed):
break
Expand Down
4 changes: 0 additions & 4 deletions Lib/test/libregrtest/single.py
Original file line number Diff line number Diff line change
Expand Up @@ -122,10 +122,6 @@ def _load_run_test(result: TestResult, runtests: RunTests) -> None:
# Load the test module and run the tests.
test_name = result.test_name
module_name = abs_module_name(test_name, runtests.test_dir)

# Remove the module from sys.module to reload it if it was already imported
sys.modules.pop(module_name, None)

test_mod = importlib.import_module(module_name)

if hasattr(test_mod, "test_main"):
Expand Down
11 changes: 11 additions & 0 deletions Lib/test/regrtestdata/import_from_tests/test_regrtest_a.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
import sys
import unittest
import test_regrtest_b.util

class Test(unittest.TestCase):
def test(self):
test_regrtest_b.util # does not fail
self.assertIn('test_regrtest_a', sys.modules)
self.assertIs(sys.modules['test_regrtest_b'], test_regrtest_b)
self.assertIs(sys.modules['test_regrtest_b.util'], test_regrtest_b.util)
self.assertNotIn('test_regrtest_c', sys.modules)
Original file line number Diff line number Diff line change
@@ -0,0 +1,9 @@
import sys
import unittest

class Test(unittest.TestCase):
def test(self):
self.assertNotIn('test_regrtest_a', sys.modules)
self.assertIn('test_regrtest_b', sys.modules)
self.assertNotIn('test_regrtest_b.util', sys.modules)
self.assertNotIn('test_regrtest_c', sys.modules)
Empty file.
11 changes: 11 additions & 0 deletions Lib/test/regrtestdata/import_from_tests/test_regrtest_c.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,11 @@
import sys
import unittest
import test_regrtest_b.util

class Test(unittest.TestCase):
def test(self):
test_regrtest_b.util # does not fail
self.assertNotIn('test_regrtest_a', sys.modules)
self.assertIs(sys.modules['test_regrtest_b'], test_regrtest_b)
self.assertIs(sys.modules['test_regrtest_b.util'], test_regrtest_b.util)
self.assertIn('test_regrtest_c', sys.modules)
19 changes: 19 additions & 0 deletions Lib/test/test_regrtest.py
Original file line number Diff line number Diff line change
Expand Up @@ -2031,6 +2031,25 @@ def test_dev_mode(self):
self.check_executed_tests(output, tests,
stats=len(tests), parallel=True)

def test_unload_tests(self):
# Test that unloading test modules does not break tests
# that import from other tests.
# The test execution order matters for this test.
# Both test_regrtest_a and test_regrtest_c which are executed before
# and after test_regrtest_b import a submodule from the test_regrtest_b
# package and use it in testing. test_regrtest_b itself does not import
# that submodule.
# Previously test_regrtest_c failed because test_regrtest_b.util in
# sys.modules was left after test_regrtest_a (making the import
# statement no-op), but new test_regrtest_b without the util attribute
# was imported for test_regrtest_b.
testdir = os.path.join(os.path.dirname(__file__),
'regrtestdata', 'import_from_tests')
tests = [f'test_regrtest_{name}' for name in ('a', 'b', 'c')]
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Would you mind to add a comment to explain the purpose of these test? By reading the code, it's unclear to me. Explain that the test execution order matters for this test.

Does the test fails if a regression is introduced? Maybe add a test_regrtest_d test checking if test_regrtest_a, test_regrtest_b and test_regrtest_c are not loaded?

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Done.

args = ['-Wd', '-E', '-bb', '-m', 'test', '--testdir=%s' % testdir, *tests]
output = self.run_python(args)
self.check_executed_tests(output, tests, stats=3)

def check_add_python_opts(self, option):
# --fast-ci and --slow-ci add "-u -W default -bb -E" options to Python
code = textwrap.dedent(r"""
Expand Down
Original file line number Diff line number Diff line change
@@ -0,0 +1,4 @@
Fixed order dependence in running tests in the same process
when a test that has submodules (e.g. test_importlib) follows a test that
imports its submodule (e.g. test_importlib.util) and precedes a test
(e.g. test_unittest or test_compileall) that uses that submodule.