Function getDeclaredLocalVercelPackageBin

packages/cli-exec/src/lookup.ts:724–767

* Resolves and validates the bin declared by the local `vercel` package.

(
  localPackage: LocalVercelPackage,
  commandBase: string
)

 * Resolves and validates the bin declared by the local `vercel` package.
 */
async function getDeclaredLocalVercelPackageBin(
  localPackage: LocalVercelPackage,
  commandBase: string
): Promise<LocalVercelPackageBinResult> {
  const { packageJson, realNodeModulesDirectory, realPackageDirectory } =
    localPackage;

  const binTarget = getPackageBinTarget(packageJson, commandBase);

  if (!binTarget) {
    return { reason: 'local vercel package does not declare bin.vercel' };
  }

  const declaredBinPath = path.resolve(realPackageDirectory, binTarget);
  const realDeclaredBinPath = await realpath(declaredBinPath);

  if (!isSubpath(realPackageDirectory, realDeclaredBinPath)) {
    return { reason: 'local vercel package bin resolves outside package' };
  }

  const unsafePackageBinReason = await getUnsafePackageBinReason(
    realNodeModulesDirectory,
    realPackageDirectory,
    realDeclaredBinPath
  );

  if (unsafePackageBinReason) {
    return {
      reason: `local vercel package bin is unsafe: ${unsafePackageBinReason}`,
    };
  }

  if (process.platform !== 'win32' && !isNodeScript(realDeclaredBinPath)) {
    try {
      await access(realDeclaredBinPath, constants.F_OK | constants.X_OK);
    } catch (error) {
      return {
        reason: `local vercel package bin is not executable: ${getErrorMessage(error)}`,
      };
    }
  }

  return { binPath: realDeclaredBinPath };
}

/**
 * Reads the declared bin target for the requested command from package data.