bpo-30215: Make re.compile() locale agnostic. (#1361)

Compiled regular expression objects with the re.LOCALE flag no longer
depend on the locale at compile time.  Only the locale at matching
time affects the result of matching.

1 files changed, 32 insertions, 0 deletions

diff --git a/Lib/test/test_re.py b/Lib/test/test_re.py
index da5c953ced..7601dc88c7 100644
--- a/Lib/test/test_re.py
+++ b/Lib/test/test_re.py
@@ -1730,6 +1730,38 @@ SUBPATTERN None 0 0
         self.assertIsNone(re.match(b'(?Li)\xc5', b'\xe5'))
         self.assertIsNone(re.match(b'(?Li)\xe5', b'\xc5'))
 
+    def test_locale_compiled(self):
+        oldlocale = locale.setlocale(locale.LC_CTYPE)
+        self.addCleanup(locale.setlocale, locale.LC_CTYPE, oldlocale)
+        for loc in 'en_US.iso88591', 'en_US.utf8':
+            try:
+                locale.setlocale(locale.LC_CTYPE, loc)
+            except locale.Error:
+                # Unsupported locale on this system
+                self.skipTest('test needs %s locale' % loc)
+
+        locale.setlocale(locale.LC_CTYPE, 'en_US.iso88591')
+        p1 = re.compile(b'\xc5\xe5', re.L|re.I)
+        p2 = re.compile(b'[a\xc5][a\xe5]', re.L|re.I)
+        p3 = re.compile(b'[az\xc5][az\xe5]', re.L|re.I)
+        p4 = re.compile(b'[^\xc5][^\xe5]', re.L|re.I)
+        for p in p1, p2, p3:
+            self.assertTrue(p.match(b'\xc5\xe5'))
+            self.assertTrue(p.match(b'\xe5\xe5'))
+            self.assertTrue(p.match(b'\xc5\xc5'))
+        self.assertIsNone(p4.match(b'\xe5\xc5'))
+        self.assertIsNone(p4.match(b'\xe5\xe5'))
+        self.assertIsNone(p4.match(b'\xc5\xc5'))
+
+        locale.setlocale(locale.LC_CTYPE, 'en_US.utf8')
+        for p in p1, p2, p3:
+            self.assertTrue(p.match(b'\xc5\xe5'))
+            self.assertIsNone(p.match(b'\xe5\xe5'))
+            self.assertIsNone(p.match(b'\xc5\xc5'))
+        self.assertTrue(p4.match(b'\xe5\xc5'))
+        self.assertIsNone(p4.match(b'\xe5\xe5'))
+        self.assertIsNone(p4.match(b'\xc5\xc5'))
+
     def test_error(self):
         with self.assertRaises(re.error) as cm:
             re.compile('(\u20ac))')