Method update

packages/dev/src/cli/test-command.js:59–63

()

    if (this.args.watch) {
      const update = () =>
        this.testHost.runTests(
          this.bundler.code,
          this.site ? this.site.manifest : null
        );
      this.bundler.on('bundle-end', update);
      if (this.site) {
        this.site.on('change', update);