vitest.dom.config.mts

import { fileURLToPath } from 'node:url';
import { defineConfig } from 'vitest/config';

/**
 * DOM-behavioral test project (#5634).
 *
 * Deliberately SEPARATE from the `tsx --test` unit profile (`npm run
 * test:data`) for two reasons:
 *
 *   1. Gate components import `@/services/i18n`, which uses `import.meta.glob`
 *      to split the locale dictionaries. tsx cannot transform that — only a
 *      Vite pipeline can — so these files are unreachable from the node:test
 *      runner no matter how the DOM globals are registered.
 *   2. `test:data` already runs ~390 files in one tsx process and OOMs at the
 *      tail in a worktree. Adding a DOM environment to that glob would make it
 *      worse; a separate runner keeps the blast radius at these files only.
 *
 * happy-dom over jsdom: 6 transitive packages instead of ~30, and it boots per
 * file fast enough that the extra CI job stays under a few seconds.
 */
export default defineConfig({
  resolve: {
    alias: {
      '@': fileURLToPath(new URL('./src', import.meta.url)),
    },
  },
  test: {
    environment: 'happy-dom',
    // Both extensions on purpose: `tests/` is 573 `.test.mjs` to 416
    // `.test.mts`, so an `.mts`-only glob would silently never run a file a
    // contributor named after the repo's more common convention — the exact
    // never-reported-test failure this directory exists to prevent.
    include: ['tests/dom/**/*.test.{mts,mjs}'],
    // Every test file installs its own listeners on a shared `document`;
    // isolate so a leaked listener cannot reach across files.
    isolate: true,
    // Single mechanism for spy cleanup — test files must NOT also call
    // vi.restoreAllMocks() or the two can drift.
    restoreMocks: true,
  },
});