Function findLockfiles

packages/angular/cli/src/package-managers/discovery.ts:31–64

* Searches a directory for lockfiles and returns a set of package managers that correspond to them. * @param host A `Host` instance for interacting with the file system. * @param directory The directory to search. * @param logger An optional logger instance. * @returns A promise that resolves to

(
  host: Host,
  directory: string,
  logger?: Logger,
)

 * @returns A promise that resolves to a set of package manager names.
 */
async function findLockfiles(
  host: Host,
  directory: string,
  logger?: Logger,
): Promise<Set<PackageManagerName>> {
  logger?.debug(`Searching for lockfiles in '${directory}'...`);

  const foundPackageManagers = new Set<PackageManagerName>();
  const checks: Promise<void>[] = [];

  for (const [name, descriptor] of Object.entries(SUPPORTED_PACKAGE_MANAGERS)) {
    const manager = name as PackageManagerName;
    for (const lockfile of descriptor.lockfiles) {
      checks.push(
        (async () => {
          try {
            const path = join(directory, lockfile);
            const stats = await host.stat(path);
            if (stats.isFile()) {
              logger?.debug(`  Found '${lockfile}'.`);
              foundPackageManagers.add(manager);
            }
          } catch {
            // File does not exist or cannot be accessed.
          }
        })(),
      );
    }
  }

  await Promise.all(checks);

  return foundPackageManagers;
}

/**
 * Checks if a given path is a directory.