Issue #18258: Fix test discovery for test_codecmaps_*.

Lib/test/multibytecodec_support.py

@@ -277,8 +277,7 @@ class TestBase_Mapping(unittest.TestCase):
     supmaps = []
     codectests = []
 
-    def __init__(self, *args, **kw):
-        unittest.TestCase.__init__(self, *args, **kw)
+    def setUp(self):
         try:
             self.open_mapping_file().close() # test it to report the error early
         except (OSError, HTTPException):

Lib/test/test_codecmaps_cn.py

@@ -25,8 +25,5 @@ class TestGB18030Map(multibytecodec_support.TestBase_Mapping,
                  'trunk/charset/data/xml/gb-18030-2000.xml'
 
 
-def test_main():
-    support.run_unittest(__name__)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()

Lib/test/test_codecmaps_hk.py

@@ -12,8 +12,5 @@ class TestBig5HKSCSMap(multibytecodec_support.TestBase_Mapping,
     encoding = 'big5hkscs'
     mapfileurl = 'http://people.freebsd.org/~perky/i18n/BIG5HKSCS-2004.TXT'
 
-def test_main():
-    support.run_unittest(__name__)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()

Lib/test/test_codecmaps_jp.py

@@ -59,8 +59,5 @@ class TestSJISX0213Map(multibytecodec_support.TestBase_Mapping,
     mapfileurl = 'http://people.freebsd.org/~perky/i18n/SHIFT_JISX0213.TXT'
 
 
-def test_main():
-    support.run_unittest(__name__)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()

Lib/test/test_codecmaps_kr.py

@@ -36,8 +36,5 @@ class TestJOHABMap(multibytecodec_support.TestBase_Mapping,
     pass_enctest = [(b'\\', '\u20a9')]
     pass_dectest = [(b'\\', '\u20a9')]
 
-def test_main():
-    support.run_unittest(__name__)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()

Lib/test/test_codecmaps_tw.py

@@ -26,8 +26,5 @@ class TestCP950Map(multibytecodec_support.TestBase_Mapping,
         (b"\xFFxy", "replace",  "\ufffdxy"),
     )
 
-def test_main():
-    support.run_unittest(__name__)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()