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| author | Alexey Izbyshev <izbyshev@ispras.ru> | 2018-10-20 00:22:31 (GMT) |
|---|---|---|
| committer | Victor Stinner <vstinner@redhat.com> | 2018-10-20 00:22:31 (GMT) |
| commit | a2670565d8f5c502388378aba1fe73023fd8c8d4 (patch) | |
| tree | a9f3a5f8e2a123aaff4f27a94c33580f0216dccd /Lib/test/support | |
| parent | 4acf6c9d4be77b968fa498569d7a1545e5e77344 (diff) | |
| download | cpython-a2670565d8f5c502388378aba1fe73023fd8c8d4.zip cpython-a2670565d8f5c502388378aba1fe73023fd8c8d4.tar.gz cpython-a2670565d8f5c502388378aba1fe73023fd8c8d4.tar.bz2 | |
bpo-32236: open() emits RuntimeWarning if buffering=1 for binary mode (GH-4842)
If buffering=1 is specified for open() in binary mode, it is silently
treated as buffering=-1 (i.e., the default buffer size).
Coupled with the fact that line buffering is always supported in Python 2,
such behavior caused several issues (e.g., bpo-10344, bpo-21332).
Warn that line buffering is not supported if open() is called with
binary mode and buffering=1.
Diffstat (limited to 'Lib/test/support')
| -rw-r--r-- | Lib/test/support/__init__.py | 32 |
1 files changed, 27 insertions, 5 deletions
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py index ed0d46d..01e8935 100644 --- a/Lib/test/support/__init__.py +++ b/Lib/test/support/__init__.py @@ -107,7 +107,8 @@ __all__ = [ # threads "threading_setup", "threading_cleanup", "reap_threads", "start_threads", # miscellaneous - "check_warnings", "check_no_resource_warning", "EnvironmentVarGuard", + "check_warnings", "check_no_resource_warning", "check_no_warnings", + "EnvironmentVarGuard", "run_with_locale", "swap_item", "swap_attr", "Matcher", "set_memlimit", "SuppressCrashReport", "sortdict", "run_with_tz", "PGO", "missing_compiler_executable", "fd_count", @@ -1253,6 +1254,30 @@ def check_warnings(*filters, **kwargs): @contextlib.contextmanager +def check_no_warnings(testcase, message='', category=Warning, force_gc=False): + """Context manager to check that no warnings are emitted. + + This context manager enables a given warning within its scope + and checks that no warnings are emitted even with that warning + enabled. + + If force_gc is True, a garbage collection is attempted before checking + for warnings. This may help to catch warnings emitted when objects + are deleted, such as ResourceWarning. + + Other keyword arguments are passed to warnings.filterwarnings(). + """ + with warnings.catch_warnings(record=True) as warns: + warnings.filterwarnings('always', + message=message, + category=category) + yield + if force_gc: + gc_collect() + testcase.assertEqual(warns, []) + + +@contextlib.contextmanager def check_no_resource_warning(testcase): """Context manager to check that no ResourceWarning is emitted. @@ -1266,11 +1291,8 @@ def check_no_resource_warning(testcase): You must remove the object which may emit ResourceWarning before the end of the context manager. """ - with warnings.catch_warnings(record=True) as warns: - warnings.filterwarnings('always', category=ResourceWarning) + with check_no_warnings(testcase, category=ResourceWarning, force_gc=True): yield - gc_collect() - testcase.assertEqual(warns, []) class CleanImport(object): |