Function wrap

src/common.js:389–488

(cmd, fn, options)

// Common wrapper for all Unix-like commands that performs glob expansion,
// command-logging, and other nice things
function wrap(cmd, fn, options) {
  options = options || {};
  return function () {
    var retValue = null;

    state.currentCmd = cmd;
    state.error = null;
    state.errorCode = 0;

    try {
      var args = [].slice.call(arguments, 0);

      // Log the command to stderr, if appropriate
      if (config.verbose) {
        console.error.apply(console, [cmd].concat(args));
      }

      // If this is coming from a pipe, let's set the pipedValue (otherwise, set
      // it to the empty string)
      state.pipedValue = (this && typeof this.stdout === 'string') ? this.stdout : '';

      if (options.unix === false) { // this branch is for exec()
        retValue = fn.apply(this, args);
      } else { // and this branch is for everything else
        if (isObject(args[0]) && args[0].constructor.name === 'Object') {
          // a no-op, allowing the syntax `touch({'-r': file}, ...)`
        } else if (args.length === 0 || typeof args[0] !== 'string' || args[0].length <= 1 || args[0][0] !== '-') {
          args.unshift(''); // only add dummy option if '-option' not already present
        }

        // flatten out arrays that are arguments, to make the syntax:
        //    `cp([file1, file2, file3], dest);`
        // equivalent to:
        //    `cp(file1, file2, file3, dest);`
        args = args.reduce(function (accum, cur) {
          if (Array.isArray(cur)) {
            return accum.concat(cur);
          }
          accum.push(cur);
          return accum;
        }, []);

        // Convert ShellStrings (basically just String objects) to regular strings
        args = args.map(function (arg) {
          if (isObject(arg) && arg.constructor.name === 'String') {
            return arg.toString();
          }
          return arg;
        });

        // Expand the '~' if appropriate
        var homeDir = os.homedir();
        args = args.map(function (arg) {
          if (typeof arg === 'string' && arg.slice(0, 2) === '~/' || arg === '~') {
            return arg.replace(/^~/, homeDir);
          }
          return arg;
        });