Function findCommandInPath

packages/cli-exec/src/lookup.ts:230–266

* Resolves the first usable command from PATH, validating local bins specially.

(
  command: string,
  pathValue: string,
  cwd: string,
  localBinSearch: LocalBinSearch,
  diagnostics: ResolutionDiagnostics
)

 * Resolves the first usable command from PATH, validating local bins specially.
 */
async function findCommandInPath(
  command: string,
  pathValue: string,
  cwd: string,
  localBinSearch: LocalBinSearch,
  diagnostics: ResolutionDiagnostics
): Promise<ResolvedCommand | null> {
  for (const directory of splitPath(pathValue)) {
    const candidate = getPathCommandCandidate(directory, command, cwd);

    try {
      const canAccess = await canAccessCommandCandidate(
        candidate,
        localBinSearch,
        diagnostics
      );

      if (canAccess) {
        const resolvedCommand = await resolveCommandCandidate(
          command,
          candidate,
          localBinSearch,
          diagnostics
        );

        if (resolvedCommand) {
          return resolvedCommand;
        }
      }
    } catch {
      // The candidate can change between access, stat, and realpath. Treat it
      // like an unusable PATH entry and keep searching.
    }
  }

  return null;
}

/**
 * Builds an absolute candidate path for one PATH entry and command name.