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tests/test_version.py

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+from __future__ import annotations
+
+import contextlib
+import io
+import unittest
+
+from a1_swap_mod_packer import APP_NAME, APP_TITLE, __version__
+from a1_swap_mod_packer.cli import create_parser
+
+
+class VersionDisplayTest(unittest.TestCase):
+    def test_app_title_uses_shared_version(self) -> None:
+        self.assertEqual(APP_TITLE, f"{APP_NAME} v{__version__}")
+
+    def test_cli_help_and_version_use_shared_version(self) -> None:
+        parser = create_parser()
+        self.assertIn(APP_TITLE, parser.format_help())
+
+        stdout = io.StringIO()
+        with self.assertRaises(SystemExit) as caught, contextlib.redirect_stdout(stdout):
+            parser.parse_args(["--version"])
+
+        self.assertEqual(caught.exception.code, 0)
+        self.assertEqual(stdout.getvalue().strip(), f"{APP_NAME} {__version__}")
+
+
+if __name__ == "__main__":
+    unittest.main()