bpo-41811: create SortKey members using first given value (GH-22316) (GH-22326)

(cherry picked from commit ae0d2a33ec)

Co-authored-by: Ethan Furman <ethan@stoneleaf.us>

Lib/pstats.py

@@ -43,9 +43,9 @@ class SortKey(str, Enum):
     TIME = 'time', 'tottime'
 
     def __new__(cls, *values):
-        obj = str.__new__(cls)
-
-        obj._value_ = values[0]
+        value = values[0]
+        obj = str.__new__(cls, value)
+        obj._value_ = value
         for other_value in values[1:]:
             cls._value2member_map_[other_value] = obj
         obj._all_values = values

Lib/test/test_pstats.py

@@ -76,5 +76,9 @@ class StatsTestCase(unittest.TestCase):
                           'calls')
 
 
+    def test_SortKey_enum(self):
+        self.assertEqual(SortKey.FILENAME, 'filename')
+        self.assertNotEqual(SortKey.FILENAME, SortKey.CALLS)
+
 if __name__ == "__main__":
     unittest.main()