Function resolveYarnScriptForProject

ng-dev/utils/resolve-yarn-bin.ts:51–101

(projectDir: string)

 * become unavailable.
 */
export async function resolveYarnScriptForProject(projectDir: string): Promise<YarnCommandInfo> {
  let info: YarnCommandInfo | undefined;

  const yarnPathFromConfig = await getYarnPathFromConfigurationIfPresent(projectDir);
  if (yarnPathFromConfig !== null) {
    const relativePath = path.relative(projectDir, yarnPathFromConfig);
    const isLocal = !relativePath.startsWith('..') && !path.isAbsolute(relativePath);

    let isTrusted = true;
    if (isLocal) {
      if (process.env['NG_DEV_TRUST_YARN_PATH'] === '1') {
        isTrusted = true;
      } else if (process.stdout.isTTY && process.stdin.isTTY) {
        isTrusted = await Prompt.confirm({
          message:
            `The project configures a local Yarn path: ${yarnPathFromConfig}.\n` +
            `Do you trust this path and want to use it?`,
          default: false,
        });
      } else {
        isTrusted = false;
      }
    }

    if (isTrusted) {
      info = {binary: 'node', args: [yarnPathFromConfig]};
    } else {
      Log.warn(
        `Ignoring local Yarn path: ${yarnPathFromConfig} as it is not trusted.\n` +
          `You can trust it by running with NG_DEV_TRUST_YARN_PATH=1 environment variable.`,
      );
    }
  }

  if (!info) {
    const yarnPathFromNpmBin = await getYarnPathFromNpmGlobalBinaries();
    if (yarnPathFromNpmBin !== null) {
      info = {binary: yarnPathFromNpmBin, args: []};
    }
  }

  info ??= {binary: 'yarn', args: []};

  const yarnVersion = await getYarnVersion(info);
  if (yarnVersion && Number(yarnVersion.split('.')[0]) < 2) {
    info.args.push('--silent');
    info.legacy = true;
  }

  return info;
}

/** Gets the path to the Yarn binary from the NPM global binary directory. */
export async function getYarnPathFromNpmGlobalBinaries(): Promise<string | null> {