gh-126727: Fix locale.nl_langinfo(locale.ERA) (GH-126730)

It now returns multiple era description segments separated by semicolons.
Previously it only returned the first segment on platforms with Glibc.

1 files changed, 45 insertions, 0 deletions

diff --git a/Lib/test/test__locale.py b/Lib/test/test__locale.py
index 7e6e296..2c75103 100644
--- a/Lib/test/test__locale.py
+++ b/Lib/test/test__locale.py
@@ -90,6 +90,14 @@ known_alt_digits = {
     'bn_IN': (100, {0: '\u09e6', 10: '\u09e7\u09e6', 99: '\u09ef\u09ef'}),
 }
 
+known_era = {
+    'C': (0, ''),
+    'en_US': (0, ''),
+    'ja_JP': (11, '+:1:2019/05/01:2019/12/31:令和:%EC元年'),
+    'zh_TW': (3, '+:1:1912/01/01:1912/12/31:民國:%EC元年'),
+    'th_TW': (1, '+:1:-543/01/01:+*:พ.ศ.:%EC %Ey'),
+}
+
 if sys.platform == 'win32':
     # ps_AF doesn't work on Windows: see bpo-38324 (msg361830)
     del known_numerics['ps_AF']
@@ -230,6 +238,43 @@ class _LocaleTests(unittest.TestCase):
         if not tested:
             self.skipTest('no suitable locales')
 
+    @unittest.skipUnless(nl_langinfo, "nl_langinfo is not available")
+    @unittest.skipUnless(hasattr(locale, 'ERA'), "requires locale.ERA")
+    @unittest.skipIf(
+        support.is_emscripten or support.is_wasi,
+        "musl libc issue on Emscripten, bpo-46390"
+    )
+    def test_era_nl_langinfo(self):
+        # Test nl_langinfo(ERA)
+        tested = False
+        for loc in candidate_locales:
+            with self.subTest(locale=loc):
+                try:
+                    setlocale(LC_TIME, loc)
+                except Error:
+                    self.skipTest(f'no locale {loc!r}')
+                    continue
+
+                with self.subTest(locale=loc):
+                    era = nl_langinfo(locale.ERA)
+                    self.assertIsInstance(era, str)
+                    if era:
+                        self.assertEqual(era.count(':'), (era.count(';') + 1) * 5, era)
+
+                    loc1 = loc.split('.', 1)[0]
+                    if loc1 in known_era:
+                        count, sample = known_era[loc1]
+                        if count:
+                            if not era:
+                                self.skipTest(f'ERA is not set for locale {loc!r} on this platform')
+                            self.assertGreaterEqual(era.count(';') + 1, count)
+                            self.assertIn(sample, era)
+                        else:
+                            self.assertEqual(era, '')
+                    tested = True
+        if not tested:
+            self.skipTest('no suitable locales')
+
     def test_float_parsing(self):
         # Bug #1391872: Test whether float parsing is okay on European
         # locales.