diff options
Diffstat (limited to 'Lib/test/test_subprocess.py')
| -rw-r--r-- | Lib/test/test_subprocess.py | 53 |
1 files changed, 21 insertions, 32 deletions
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py index f065b9c..e45701d 100644 --- a/Lib/test/test_subprocess.py +++ b/Lib/test/test_subprocess.py @@ -4,6 +4,7 @@ from test import support from test.support import check_sanitizer from test.support import import_helper from test.support import os_helper +from test.support import strace_helper from test.support import warnings_helper from test.support.script_helper import assert_python_ok import subprocess @@ -3415,7 +3416,7 @@ class POSIXProcessTestCase(BaseTestCase): @unittest.skipIf(not sysconfig.get_config_var("HAVE_VFORK"), "vfork() not enabled by configure.") - @unittest.skipIf(sys.platform != "linux", "Linux only, requires strace.") + @strace_helper.requires_strace() @mock.patch("subprocess._USE_POSIX_SPAWN", new=False) def test_vfork_used_when_expected(self): # This is a performance regression test to ensure we default to using @@ -3423,36 +3424,25 @@ class POSIXProcessTestCase(BaseTestCase): # Technically this test could pass when posix_spawn is used as well # because libc tends to implement that internally using vfork. But # that'd just be testing a libc+kernel implementation detail. - strace_binary = "/usr/bin/strace" - # The only system calls we are interested in. - strace_filter = "--trace=clone,clone2,clone3,fork,vfork,exit,exit_group" - true_binary = "/bin/true" - strace_command = [strace_binary, strace_filter] - try: - does_strace_work_process = subprocess.run( - strace_command + [true_binary], - stderr=subprocess.PIPE, - stdout=subprocess.DEVNULL, - ) - rc = does_strace_work_process.returncode - stderr = does_strace_work_process.stderr - except OSError: - rc = -1 - stderr = "" - if rc or (b"+++ exited with 0 +++" not in stderr): - self.skipTest("strace not found or not working as expected.") + # Are intersted in the system calls: + # clone,clone2,clone3,fork,vfork,exit,exit_group + # Unfortunately using `--trace` with that list to strace fails because + # not all are supported on all platforms (ex. clone2 is ia64 only...) + # So instead use `%process` which is recommended by strace, and contains + # the above. + true_binary = "/bin/true" + strace_args = ["--trace=%process"] with self.subTest(name="default_is_vfork"): - vfork_result = assert_python_ok( - "-c", - textwrap.dedent(f"""\ - import subprocess - subprocess.check_call([{true_binary!r}])"""), - __run_using_command=strace_command, + vfork_result = strace_helper.strace_python( + f"""\ + import subprocess + subprocess.check_call([{true_binary!r}])""", + strace_args ) # Match both vfork() and clone(..., flags=...|CLONE_VFORK|...) - self.assertRegex(vfork_result.err, br"(?i)vfork") + self.assertRegex(vfork_result.event_bytes, br"(?i)vfork") # Do NOT check that fork() or other clones did not happen. # If the OS denys the vfork it'll fallback to plain fork(). @@ -3465,9 +3455,8 @@ class POSIXProcessTestCase(BaseTestCase): ("setgroups", "", "extra_groups=[]", True), ): with self.subTest(name=sub_name): - non_vfork_result = assert_python_ok( - "-c", - textwrap.dedent(f"""\ + non_vfork_result = strace_helper.strace_python( + f"""\ import subprocess {preamble} try: @@ -3475,11 +3464,11 @@ class POSIXProcessTestCase(BaseTestCase): [{true_binary!r}], **dict({sp_kwarg})) except PermissionError: if not {expect_permission_error}: - raise"""), - __run_using_command=strace_command, + raise""", + strace_args ) # Ensure neither vfork() or clone(..., flags=...|CLONE_VFORK|...). - self.assertNotRegex(non_vfork_result.err, br"(?i)vfork") + self.assertNotRegex(non_vfork_result.event_bytes, br"(?i)vfork") @unittest.skipUnless(mswindows, "Windows specific tests") |