commit_check/config_merger.py (4)

51-55: Preserve exception chain with raise ... from.

When re-raising a ValueError inside an except block, use raise ... from to maintain the exception chain for better debugging.

♻️ Suggested fix

     if isinstance(value, str):
         try:
             return int(value.strip())
         except ValueError as err:
-            raise ValueError(f"Cannot parse '{value}' as integer")
+            raise ValueError(f"Cannot parse '{value}' as integer") from err
     raise TypeError(f"Cannot convert {type(value).__name__} to int")

---

100-122: Consider annotating mutable class attribute with ClassVar.

The ENV_VAR_MAPPING dictionary is a class-level constant that should be annotated with typing.ClassVar to indicate it's shared across all instances and not meant to be modified per-instance.

♻️ Suggested fix

+from typing import ClassVar
+
 class ConfigMerger:
     """Merges configurations from multiple sources with priority: CLI > Env > TOML > Defaults."""

     # Mapping of environment variable names to config keys
-    ENV_VAR_MAPPING: Dict[str, Tuple[str, str, Callable[[Any], Any]]] = {
+    ENV_VAR_MAPPING: ClassVar[Dict[str, Tuple[str, str, Callable[[Any], Any]]]] = {

---

135-137: Warning output to stdout may interfere with piped workflows.

Using print() for warnings sends output to stdout, which could interfere with scenarios where commit-check output is piped. Consider using sys.stderr or the logging module instead.

♻️ Suggested fix

+import sys
+
                 except (ValueError, TypeError) as e:
                     # Log warning but don't fail - just skip invalid env vars
-                    print(f"Warning: Invalid value for {env_var}: {e}")
+                    print(f"Warning: Invalid value for {env_var}: {e}", file=sys.stderr)

---

144-222: Consider reducing repetition in parse_cli_args.

The method has significant repetition with the hasattr/is not None pattern. A data-driven approach similar to ENV_VAR_MAPPING would reduce maintenance burden and be more consistent.

♻️ Example refactor approach

CLI_ARG_MAPPING = {
    # (attr_name, section, config_key)
    ("conventional_commits", "commit", "conventional_commits"),
    ("subject_capitalized", "commit", "subject_capitalized"),
    ("subject_imperative", "commit", "subject_imperative"),
    # ... etc
}

`@staticmethod`
def parse_cli_args(args: argparse.Namespace) -> Dict[str, Any]:
    config: Dict[str, Any] = {"commit": {}, "branch": {}}
    for attr, section, key in ConfigMerger.CLI_ARG_MAPPING:
        value = getattr(args, attr, None)
        if value is not None:
            config[section][key] = value
    config = {k: v for k, v in config.items() if v}
    return config

commit_check/main.py (1)

355-360: Dead code branch in stdin handling.

The elif not any(...) block at line 355-357 contains only a pass statement and has no effect. This could be simplified or removed.

♻️ Suggested simplification

             if args.message == "":
                 # Only set stdin_content if there's actual piped input
                 stdin_content = stdin_reader.read_piped_input()
                 if not stdin_content:
                     # No stdin and no file - let validators get data from git themselves
                     stdin_content = None
             else:
                 # Message is a file path
                 commit_file_path = args.message
-        elif not any([args.branch, args.author_name, args.author_email]):
-            # If no specific validation type is requested, don't read stdin
-            pass
-        else:
+        elif any([args.branch, args.author_name, args.author_email]):
             # For non-message validations (branch, author), check for stdin input
             stdin_content = stdin_reader.read_piped_input()

tests/config_merger_test.py (1)

254-261: Remove unused tmp_path fixture parameter.

The tmp_path fixture parameter is declared but not used in this test method.

♻️ Suggested fix

-    def test_default_config_only(self, tmp_path):
+    def test_default_config_only(self):
         # No TOML file, no env vars, no CLI args
         args = argparse.Namespace()
         config = ConfigMerger.from_all_sources(args)