Add misc check to prevent vim modelines

We deprecated vim modelines. The introduced misc check will keep old pull requests from
re-introducing vim modelines.

scripts/dev/misc_checks.py

@@ -397,6 +397,25 @@ def check_userscript_shebangs(_args: argparse.Namespace) -> bool:
     return ok
 
 
+def check_vim_modelines(args: argparse.Namespace) -> bool:
+    """Check that we're not using vim modelines."""
+    ok = True
+    try:
+        for path in _get_files(verbose=args.verbose):
+            with tokenize.open(str(path)) as f:
+                for num, line in enumerate(f, start=1):
+                    if not line.startswith("# vim:"):
+                        continue
+                    print(f"{path}:{num}: Remove vim modeline "
+                          "(deprecated in favor of .editorconfig)")
+                    ok = False
+    except Exception:
+        traceback.print_exc()
+        ok = False
+
+    return ok
+
+
 def main() -> int:
     checkers = {
         'git': check_git,
@@ -406,6 +425,7 @@ def main() -> int:
         'userscript-descriptions': check_userscripts_descriptions,
         'userscript-shebangs': check_userscript_shebangs,
         'changelog-urls': check_changelog_urls,
+        'vim-modelines': check_vim_modelines,
     }
 
     parser = argparse.ArgumentParser()