lint-staged.config.mjs

// Dynamic lint-staged config: routes each staged file to the right autofix tool
// at commit time instead of hardcoding an extension→tool map that could fall
// out of date. eslint and ember-template-lint cover a small, deliberate set of
// extensions; everything else is handed to prettier IF prettier itself can
// format it — `getFileInfo` is prettier's own source of truth, so new formats
// (or a prettier upgrade that adds one) are picked up automatically with no
// edit here. All routing goes through scripts/lint-autofix.mjs, which applies
// fixes, re-stages, and warns without ever blocking the commit.
import { getFileInfo } from 'prettier';
import { basename, dirname, extname, join } from 'node:path';
import { fileURLToPath } from 'node:url';

// pnpm owns these files: it (re)writes them with its own serializer, so no
// lint tool usefully applies — prettier reformatting pnpm-workspace.yaml just
// fights pnpm's next rewrite, and pnpm-lock.yaml is prettier-ignored anyway.
// Drop them before routing so they're never scanned or handed to any tool.
const PNPM_OWNED_FILES = new Set(['pnpm-lock.yaml', 'pnpm-workspace.yaml']);

// Trees whose contents are copied in verbatim from another repo and must keep
// that repo's bytes. `.prettierignore` already covers them, but eslint applies
// prettier formatting through eslint-plugin-prettier and never consults
// `.prettierignore` — so without this skip, staging a copied `.gts` reformats
// it and drifts the copy from its source. Match on a path segment so absolute
// staged paths work.
const VERBATIM_COPIED_TREES = [
  // Licensed FileDef sample files whose bytes must match the integrity
  // manifest in the sibling SOURCES.md.
  '/packages/experiments-realm/filedef-fixtures/samples/',
  // Vendored third-party bundles and data in Pret UI; each directory's
  // README.md records the upstream version and how the bytes were built.
  '/packages/pretui/color/index.js',
  '/packages/pretui/zxcvbn/index.js',
  '/packages/pretui/sigpad/index.js',
  '/packages/pretui/emoji-data/data.ts',
  '/packages/pretui/gridstack/index.js',
  '/packages/pretui/media-chrome/index.js',
  '/packages/pretui/surfaces/canvas/index.js',
  '/packages/pretui/surfaces/layout/index.js',
  '/packages/pretui/cropper/index.js',
  '/packages/pretui/model-viewer/index.js',
  '/packages/pretui/photoswipe/index.js',
  '/packages/pretui/photoswipe/style.ts',
  '/packages/pretui/plot/index.js',
  '/packages/pretui/qrcode/index.js',
  '/packages/pretui/wavesurfer/index.js',
  '/packages/pretui/surfaces/grid/index.js',
];
const isVerbatimCopy = (file) => {
  const posix = file.replace(/\\/g, '/');
  return VERBATIM_COPIED_TREES.some((tree) => posix.includes(tree));
};

// Resolve .prettierignore next to this config (repo root) rather than relying
// on cwd, so getFileInfo's `ignored` verdict matches what the prettier CLI in
// lint-autofix.mjs actually honors.
const PRETTIER_IGNORE = join(
  dirname(fileURLToPath(import.meta.url)),
  '.prettierignore',
);

// eslint also applies prettier formatting for these via eslint-plugin-prettier,
// so they must NOT also go to prettier (that would double-process and fight
// over formatting). Matches what CI's `eslint .` lints.
const ESLINT_EXTENSIONS = new Set(['.js', '.ts', '.gjs', '.gts']);
// .gjs / .gts are routed to ember-template-lint in addition to eslint:
// eslint sees the surrounding JS/TS but can't lint the inline <template>
// blocks, so template-lint rules (e.g. no-unnecessary-curly-parens) would
// otherwise only fire in CI's `lint:hbs` (`ember-template-lint .`).
const TEMPLATE_EXTENSIONS = new Set(['.hbs', '.gjs', '.gts']);

const AUTOFIX = 'node scripts/lint-autofix.mjs';

// POSIX-safe single-quoting for paths embedded in the returned shell commands
// (staged paths can contain spaces).
const quote = (s) => `'${s.replace(/'/g, `'\\''`)}'`;

export default async (stagedFiles) => {
  const eslintFiles = [];
  const templateFiles = [];
  const prettierFiles = [];

  for (const file of stagedFiles) {
    if (PNPM_OWNED_FILES.has(basename(file))) continue;
    if (isVerbatimCopy(file)) continue;
    const ext = extname(file);
    let routed = false;
    if (ESLINT_EXTENSIONS.has(ext)) {
      eslintFiles.push(file);
      routed = true;
    }
    if (TEMPLATE_EXTENSIONS.has(ext)) {
      templateFiles.push(file);
      routed = true;
    }
    if (!routed) {
      // Ask prettier whether it can format this file. resolveConfig picks up
      // the repo's .prettierrc (and its plugins) and ignorePath consults
      // .prettierignore, so the decision matches what `prettier --write` would
      // actually do — including skipping ignored files like pnpm-lock.yaml.
      const { inferredParser, ignored } = await getFileInfo(file, {
        resolveConfig: true,
        ignorePath: PRETTIER_IGNORE,
      });
      if (inferredParser && !ignored) prettierFiles.push(file);
    }
  }

  const commands = [];
  if (eslintFiles.length) {
    commands.push(`${AUTOFIX} eslint ${eslintFiles.map(quote).join(' ')}`);
  }
  if (templateFiles.length) {
    commands.push(
      `${AUTOFIX} ember-template-lint ${templateFiles.map(quote).join(' ')}`,
    );
  }
  if (prettierFiles.length) {
    commands.push(`${AUTOFIX} prettier ${prettierFiles.map(quote).join(' ')}`);
  }
  return commands;
};