Function getMacPATH

src/back/util/misc.ts:394–453

(shell?: string)

 * @returns The user's PATH in that shell.
 */
export async function getMacPATH(shell?: string): Promise<string> {
  // If we weren't given a shell override, detect the user's default shell.
  if (!shell) {
    // Read the user's shell using dscl. No clue how it works, deal with it.
    const shellDetector = child_process.spawn('dscl', ['.', '-read', os.homedir(), 'UserShell'], {
      shell: false
    });
    // Get the full output and wait for the process to exit.
    let builder = '';
    shellDetector.stdout.on('data', (chunk) => {
      builder += chunk;
    });
    await new Promise<void>(resolve => {
      shellDetector.on('exit', () => {
        resolve();
      });
    });
    // Look for a known shell in the output.
    for (const option of ['bash', 'zsh', 'ksh', 'tcsh', 'csh']) {
      const matchresult = builder.match(new RegExp('/.*' + option));
      if (matchresult) {
        shell = matchresult[0];
        break;
      }
    }
  }
  // Default to bash if none of the other shells are found.
  shell = shell ?? '/bin/bash';
  const spawnOpts: child_process.SpawnOptionsWithoutStdio = {
    shell: false
  };
  // Different shells require different arguments to start in "login" (profile-reading) mode.
  const loginArgs = [];
  switch (shell.slice(shell.lastIndexOf('/') + 1)) {
    case 'bash':
    case 'zsh':
    case 'ksh':
      loginArgs.push('-i', '-l');
      break;
    case 'tcsh':
    case 'csh':
      loginArgs.push('-i');
      spawnOpts.argv0 = '-' + shell.slice(shell.lastIndexOf('/') + 1);
      break;
  }
  // Run the shell, tell it to echo $PATH when it's done with init.
  const pathDetector = child_process.spawn(shell, [...loginArgs, '-c', 'echo $PATH'], spawnOpts);
  // Get the full output and wait for the process to exit.
  let builder = '';
  pathDetector.stdout.on('data', (chunk) => {
    builder += chunk;
  });
  await new Promise<void>(resolve => {
    pathDetector.on('exit', () => {
      resolve();
    });
  });
  // Trim any whitespace, etc.