vitest.config.mts

import { fileURLToPath } from 'node:url';
import { svelte } from '@sveltejs/vite-plugin-svelte';
import { defineConfig } from 'vitest/config';
import { WASM_RUNTIME_FLAGS } from './src/extraction/wasm-runtime-flags';

/**
 * One process, two Vitest projects. The engine stays in Node; the UI package
 * test alone gets Svelte compilation, jsdom and browser resolution conditions.
 */
export default defineConfig({
  test: {
    globals: true,
    environment: 'node',
    include: ['__tests__/**/*.test.ts'],
    // Suites that spawn the built CLI need a current dist/ (#1879), and the end
    // of the run removes any home sandbox its own test file could not.
    globalSetup: ['./__tests__/global-setup-dist.ts', './__tests__/global-setup-home-sandbox.ts'],
    // A throwaway home dir (and git global config) per test file, so nothing
    // the suite runs can write to the developer's real one (#2275).
    setupFiles: ['./__tests__/setup-home-sandbox.ts'],
    /**
     * Since Vitest 3 a synchronous test or hook fails when it outlasts its
     * timeout. Under Vitest 2 the timer could not fire until the body had
     * returned, so a body blocked in `spawnSync` never timed out at all. Hundreds
     * of tests here block on the built CLI, and on a loaded machine the 5 s and
     * 10 s defaults would turn them into flakes.
     */
    testTimeout: 30_000,
    hookTimeout: 60_000,
    env: {
      /**
       * The suite spawns real CLI/MCP processes; without this they would write
       * telemetry state into the contributor's real ~/.codegraph and count test
       * tool calls as real usage. The telemetry unit tests are unaffected —
       * they inject their own `env` via the Telemetry constructor.
       */
      CODEGRAPH_TELEMETRY: '0',
    },
    /**
     * The same V8 flags every real launch path passes (the bundled launcher,
     * the CLI's self re-exec, refresh-launcher): keep tree-sitter grammar
     * compilation on the Liftoff baseline tier. Without them a pool worker
     * runs the grammars on the turboshaft optimizing tier, and once enough
     * parses have warmed a grammar function up, its background tier-up job
     * exhausts a compiler Zone and aborts the worker — `Fatal process out of
     * memory: Zone`, surfaced by vitest only as "Worker exited unexpectedly"
     * with the rest of the file's tests silently unrun (#1779, #1883; the
     * product-side story is in wasm-runtime-flags.ts, #293/#298). V8 flags are
     * process-global, so the parse worker threads a test spawns are covered
     * too. Vitest 4 reads `test.execArgv`; the 2.x `poolOptions.forks.execArgv`
     * is silently ignored here. The engine project inherits it via `extends`.
     */
    execArgv: [...WASM_RUNTIME_FLAGS],
    coverage: {
      provider: 'v8',
      reporter: ['text', 'json', 'html'],
    },
    projects: [
      {
        extends: true,
        test: {
          name: 'engine',
          include: ['__tests__/**/*.test.ts'],
          // A lazy `require` of a `.ts` file can't run under vitest's module
          // transform: see src/lazy-engine.ts.
          alias: [
            {
              find: /^\.\/lazy-engine$/,
              replacement: fileURLToPath(new URL('./__tests__/lazy-engine-eager.ts', import.meta.url)),
            },
            {
              find: /^\.\/lazy-frameworks$/,
              replacement: fileURLToPath(new URL('./__tests__/lazy-frameworks-eager.ts', import.meta.url)),
            },
          ],
          exclude: ['**/node_modules/**', '**/dist/**', '__tests__/ui-package.test.ts'],
        },
      },
      {
        // Browser package resolution must not leak into the engine project:
        // web-tree-sitter and other dual packages would resolve differently.
        // And no `extends`: a project that extends takes the base's `include`
        // too, so every engine suite would run a second time inside jsdom.
        extends: false,
        plugins: [svelte({ configFile: 'ui/svelte.config.js' })],
        resolve: { conditions: ['browser'] },
        test: {
          name: 'ui',
          globals: true,
          include: ['__tests__/ui-package.test.ts'],
          environment: 'jsdom',
          server: {
            deps: {
              // @xyflow/svelte ships source .svelte files that Node cannot load.
              inline: [/@xyflow\/svelte/],
            },
          },
        },
      },
    ],
  },
});