gh-152305: Fix pure-Python time.strftime AttributeError on %Y/%G/%C/%F

Author: tonghuaroot

Lib/_pydatetime.py

@@ -273,11 +273,11 @@ def _wrap_strftime(object, format, timetuple):
                 # Note that datetime(1000, 1, 1).strftime('%G') == '1000' so
                 # year 1000 for %G can go on the fast path.
                 elif ((ch in 'YG' or ch in 'FC') and
-                        object.year < 1000 and _need_normalize_century()):
+                        timetuple[0] < 1000 and _need_normalize_century()):
                     if ch == 'G':
                         year = int(_time.strftime("%G", timetuple))
                     else:
-                        year = object.year
+                        year = timetuple[0]
                     if ch == 'C':
                         push('{:02}'.format(year // 100))
                     else:

Lib/test/datetimetester.py

@@ -4084,6 +4084,13 @@ def test_strftime(self):
         # A naive object replaces %z, %:z and %Z with empty strings.
         self.assertEqual(t.strftime("'%z' '%:z' '%Z'"), "'' '' ''")
 
+        # gh-152305: the year directives must not raise on a time (1900-01-01).
+        t1230 = self.theclass(12, 30)
+        self.assertEqual(t1230.strftime('%Y'), '1900')
+        self.assertEqual(t1230.strftime('%G'), '1900')
+        self.assertEqual(t1230.strftime('%C'), '19')
+        self.assertEqual(t1230.strftime('%F'), '1900-01-01')
+
         # bpo-34482: Check that surrogates don't cause a crash.
         try:
             t.strftime('%H\ud800%M')

Misc/NEWS.d/next/Library/2026-06-26-15-41-34.gh-issue-152305.WnbbBc.rst

@@ -0,0 +1,3 @@
+Fix :meth:`datetime.time.strftime` raising :exc:`AttributeError` for the
+``%Y``, ``%G``, ``%C`` and ``%F`` directives in the pure-Python
+implementation. Patch by tonghuaroot.