[3.12] gh-53203: Improve tests for strptime() (GH-125090) (GH-125093)

Run them with different locales and different date and time. Add the @run_with_locales() decorator to run the test with multiple locales. Improve the run_with_locale() context manager/decorator -- it now catches only expected exceptions and reports the test as skipped if no appropriate locale is available. (cherry picked from commit 19984fe)

Author: serhiy-storchaka

Lib/test/pickletester.py

@@ -26,7 +26,7 @@
 from test import support
 from test.support import os_helper
 from test.support import (
- TestFailed, run_with_locale, no_tracing,
+ TestFailed, run_with_locales, no_tracing,
  _2G, _4G, bigmemtest
  )
 from test.support.import_helper import forget
@@ -2591,7 +2591,7 @@ def test_float(self):
  got = self.loads(pickle)
  self.assert_is_copy(value, got)
 
- @run_with_locale('LC_ALL', 'de_DE', 'fr_FR')
+ @run_with_locales('LC_ALL', 'de_DE', 'fr_FR', '')
  def test_float_format(self):
  # make sure that floats are formatted locale independent with proto 0
  self.assertEqual(self.dumps(1.2, 0)[0:3], b'F1.')

Lib/test/support/__init__.py

@@ -854,8 +854,8 @@ def check_sizeof(test, o, size):
  test.assertEqual(result, size, msg)
 
 #=======================================================================
-# Decorator for running a function in a different locale, correctly resetting
-# it afterwards.
+# Decorator/context manager for running a code in a different locale,
+# correctly resetting it afterwards.
 
 @contextlib.contextmanager
 def run_with_locale(catstr, *locales):
@@ -866,23 +866,68 @@ def run_with_locale(catstr, *locales):
  except AttributeError:
  # if the test author gives us an invalid category string
  raise
- except:
+ except Exception:
  # cannot retrieve original locale, so do nothing
  locale = orig_locale = None
+ if '' not in locales:
+ raise unittest.SkipTest('no locales')
  else:
  for loc in locales:
  try:
  locale.setlocale(category, loc)
  break
- except:
+ except locale.Error:
  pass
+ else:
+ if '' not in locales:
+ raise unittest.SkipTest(f'no locales {locales}')
 
  try:
  yield
  finally:
  if locale and orig_locale:
  locale.setlocale(category, orig_locale)
 
+#=======================================================================
+# Decorator for running a function in multiple locales (if they are
+# availasble) and resetting the original locale afterwards.
+
+def run_with_locales(catstr, *locales):
+ def deco(func):
+ @functools.wraps(func)
+ def wrapper(self, /, *args, **kwargs):
+ dry_run = '' in locales
+ try:
+ import locale
+ category = getattr(locale, catstr)
+ orig_locale = locale.setlocale(category)
+ except AttributeError:
+ # if the test author gives us an invalid category string
+ raise
+ except Exception:
+ # cannot retrieve original locale, so do nothing
+ pass
+ else:
+ try:
+ for loc in locales:
+ with self.subTest(locale=loc):
+ try:
+ locale.setlocale(category, loc)
+ except locale.Error:
+ self.skipTest(f'no locale {loc!r}')
+ else:
+ dry_run = False
+ func(self, *args, **kwargs)
+ finally:
+ locale.setlocale(category, orig_locale)
+ if dry_run:
+ # no locales available, so just run the test
+ # with the current locale
+ with self.subTest(locale=None):
+ func(self, *args, **kwargs)
+ return wrapper
+ return deco
+
 #=======================================================================
 # Decorator for running a function in a specific timezone, correctly
 # resetting it afterwards.

Lib/test/test_codecs.py

@@ -2,7 +2,6 @@
 import contextlib
 import copy
 import io
-import locale
 import pickle
 import sys
 import unittest
@@ -1700,16 +1699,10 @@ def test_getwriter(self):
  self.assertRaises(TypeError, codecs.getwriter)
  self.assertRaises(LookupError, codecs.getwriter, "__spam__")
 
+ @support.run_with_locale('LC_CTYPE', 'tr_TR')
  def test_lookup_issue1813(self):
  # Issue #1813: under Turkish locales, lookup of some codecs failed
  # because 'I' is lowercased as "ı" (dotless i)
- oldlocale = locale.setlocale(locale.LC_CTYPE)
- self.addCleanup(locale.setlocale, locale.LC_CTYPE, oldlocale)
- try:
- locale.setlocale(locale.LC_CTYPE, 'tr_TR')
- except locale.Error:
- # Unsupported locale on this system
- self.skipTest('test needs Turkish locale')
  c = codecs.lookup('ASCII')
  self.assertEqual(c.name, 'ascii')
 

Lib/test/test_decimal.py

@@ -1242,7 +1242,7 @@ def get_fmt(x, override=None, fmt='n'):
  self.assertEqual(get_fmt(Decimal('-1.5'), dotsep_wide, '020n'),
  '-0\u00b4000\u00b4000\u00b4000\u00b4001\u00bf5')
 
- @run_with_locale('LC_ALL', 'ps_AF')
+ @run_with_locale('LC_ALL', 'ps_AF', '')
  def test_wide_char_separator_decimal_point(self):
  # locale with wide char separator and decimal point
  Decimal = self.decimal.Decimal

Lib/test/test_float.py

@@ -153,7 +153,7 @@ def check(s):
  # non-UTF-8 byte string
  check(b'123\xa0')
 
- @support.run_with_locale('LC_NUMERIC', 'fr_FR', 'de_DE')
+ @support.run_with_locale('LC_NUMERIC', 'fr_FR', 'de_DE', '')
  def test_float_with_comma(self):
  # set locale to something that doesn't use '.' for the decimal point
  # float must not accept the locale specific decimal point but

Lib/test/test_imaplib.py

@@ -57,7 +57,7 @@ def timevalues(self):
  timezone(timedelta(0, 2 * 60 * 60))),
  '"18-May-2033 05:33:20 +0200"']
 
- @run_with_locale('LC_ALL', 'de_DE', 'fr_FR')
+ @run_with_locale('LC_ALL', 'de_DE', 'fr_FR', '')
  # DST rules included to work around quirk where the Gnu C library may not
  # otherwise restore the previous time zone
  @run_with_tz('STD-1DST,M3.2.0,M11.1.0')