fix: exit non-zero when torrentzip check fails

scripts/torrentzip.py

@@ -114,8 +114,8 @@ def identify_romset(
     return None
 
 
-def main() -> None:
-    """Entry point."""
+def main() -> int:
+    """Entry point: 1 when a checked archive is not TorrentZip."""
     parser = argparse.ArgumentParser(description="TorrentZip builder and checker")
     parser.add_argument("--check", metavar="ZIP", help="report TorrentZip conformance")
     parser.add_argument("--rebuild", metavar="ZIP", help="normalize an archive")
@@ -130,14 +130,14 @@ def main() -> None:
         print(f"  md5:       {hashlib.md5(data).hexdigest()}")
         print(f"  rebuilt:   {hashlib.md5(rebuilt).hexdigest()}")
         print(f"  conform:   {data == rebuilt}")
-        return
+        return 0 if data == rebuilt else 1
 
     if args.rebuild:
         data = rebuild_torrentzip(args.rebuild)
         dest = args.output or args.rebuild
         Path(dest).write_bytes(data)
         print(f"{dest}: {len(data)} bytes, md5 {hashlib.md5(data).hexdigest()}")
-        return
+        return 0
 
     parser.error("nothing to do: pass --check or --rebuild")
 

tests/test_torrentzip.py

@@ -153,5 +153,29 @@ def _as_file(test: unittest.TestCase, data: bytes) -> str:
     return path
 
 
+class CheckModeExitCode(unittest.TestCase):
+    """--check printed `conform: False` and exited 0, so no script could use it."""
+
+    def test_the_exit_code_follows_conformance(self):
+        import subprocess
+
+        with tempfile.TemporaryDirectory(dir=os.path.join(REPO_ROOT, "tmp")) as directory:
+            plain = os.path.join(directory, "plain.zip")
+            with zipfile.ZipFile(plain, "w") as zf:
+                zf.writestr("a.bin", b"rom")
+            torrent = os.path.join(directory, "torrent.zip")
+            with open(torrent, "wb") as handle:
+                handle.write(build_torrentzip([("a.bin", b"rom")]))
+            script = os.path.join(REPO_ROOT, "scripts", "torrentzip.py")
+            codes = [
+                subprocess.run(
+                    [sys.executable, script, "--check", path],
+                    capture_output=True, check=False, timeout=60,
+                ).returncode
+                for path in (plain, torrent)
+            ]
+        self.assertEqual(codes, [1, 0])
+
+
 if __name__ == "__main__":
     unittest.main()