gh-53950: Clear MESSAGES in msgfmt

Lib/test/test_tools/test_msgfmt.py

@@ -43,6 +43,7 @@ def test_compilation(self):
                         actual = GNUTranslations(f)
 
                     self.assertDictEqual(actual._catalog, expected._catalog)
+                    self.assertFalse(msgfmt.MESSAGES)
 
     def test_binary_header(self):
         with temp_cwd():
@@ -145,12 +146,6 @@ def test_generic_syntax_error(self):
 
 
 class POParserTest(unittest.TestCase):
-    @classmethod
-    def tearDownClass(cls):
-        # msgfmt uses a global variable to store messages,
-        # clear it after the tests.
-        msgfmt.MESSAGES.clear()
-
     def test_strings(self):
         # Test that the PO parser correctly handles and unescape
         # strings in the PO file.
@@ -202,8 +197,6 @@ def test_strings(self):
                     # check the result.
                     po = f'msgid {po_string}\nmsgstr "translation"'
                     Path('messages.po').write_text(po)
-                    # Reset the global MESSAGES dictionary
-                    msgfmt.MESSAGES.clear()
                     msgfmt.make('messages.po', 'messages.mo')
 
                     with open('messages.mo', 'rb') as f:
@@ -235,8 +228,6 @@ def test_strings(self):
                 with self.subTest(string=invalid_string):
                     po = f'msgid {invalid_string}\nmsgstr "translation"'
                     Path('messages.po').write_text(po)
-                    # Reset the global MESSAGES dictionary
-                    msgfmt.MESSAGES.clear()
                     with self.assertRaises(Exception):
                         msgfmt.make('messages.po', 'messages.mo')
 

Misc/NEWS.d/next/Tools-Demos/2025-05-02-19-56-00.gh-issue-53950.asdhss.rst

@@ -0,0 +1 @@
+Fix bug in :program:`msgfmt` where ``MESSAGES`` was not cleared.

Tools/i18n/msgfmt.py

@@ -99,6 +99,9 @@ def generate():
 
 
 def make(filename, outfile):
+    global MESSAGES
+    MESSAGES.clear()
+
     ID = 1
     STR = 2
     CTXT = 3