commitlint.config.cjs

const allowedTypes = [
  "build",
  "chore",
  "ci",
  "docs",
  "feat",
  "fix",
  "perf",
  "refactor",
  "revert",
  "simplify",
  "style",
  "test",
];

// GitHub appends " (#<number>)" to a squash-merged pull request's title. The
// reference is a link GitHub adds after review, so the length limit measures
// only the header the author wrote.
const pullRequestReference = / \(#\d+\)$/;

module.exports = {
  defaultIgnores: false,
  plugins: [
    {
      rules: {
        "authored-header-max-length": (parsed, _when, maxLength) => {
          const authored = (parsed.header ?? "").replace(pullRequestReference, "");
          return [
            authored.length <= maxLength,
            `header must not be longer than ${maxLength} characters excluding a trailing pull request reference, current length is ${authored.length}`,
          ];
        },
      },
    },
  ],
  ignores: [
    (message) => /^Merge[ \t]/.test(message),
    // Git-generated revert headers quote the reverted subject verbatim, so the
    // header cannot satisfy the typed-header rules. Accept the canonical
    // header whether the body is Git's autogenerated "This reverts commit"
    // line or an author-written explanation of why the revert was needed.
    (message) => /^Revert "[^\r\n]+"(?:\r?\n(?:\r?\n[\s\S]*)?)?$/.test(message),
  ],
  parserPreset: {
    name: "tracedecay",
    parserOpts: {
      headerCorrespondence: ["type", "scope", "breaking", "subject"],
      headerPattern: /^(\w*)(?:\(([A-Za-z0-9._/-]+)\))?(!)?: ([^\s].*)$/,
    },
  },
  rules: {
    "authored-header-max-length": [2, "always", 72],
    "subject-empty": [2, "never"],
    "type-empty": [2, "never"],
    "type-enum": [2, "always", allowedTypes],
  },
};