/**
   * @fileoverview An inherited `glob.GlobSync` to support .gitignore patterns.
   * @author Kael Zhang
   */
  "use strict";
  
  //------------------------------------------------------------------------------
  // Requirements
  //------------------------------------------------------------------------------
  
  const Sync = require("glob").GlobSync,
      util = require("util");
  
  //------------------------------------------------------------------------------
  // Private
  //------------------------------------------------------------------------------
  
  const IGNORE = Symbol("ignore");
  
  /**
   * Subclass of `glob.GlobSync`
   * @param {string}     pattern      Pattern to be matched.
   * @param {Object}     options      `options` for `glob`
   * @param {function()} shouldIgnore Method to check whether a directory should be ignored.
   * @constructor
   */
  function GlobSync(pattern, options, shouldIgnore) {
  
      /**
       * We don't put this thing to argument `options` to avoid
       * further problems, such as `options` validation.
       *
       * Use `Symbol` as much as possible to avoid confliction.
       */
      this[IGNORE] = shouldIgnore;
  
      Sync.call(this, pattern, options);
  }
  
  util.inherits(GlobSync, Sync);
  
  /* eslint no-underscore-dangle: ["error", { "allow": ["_readdir", "_mark"] }] */
  
  GlobSync.prototype._readdir = function(abs, inGlobStar) {
  
      /**
       * `options.nodir` makes `options.mark` as `true`.
       * Mark `abs` first
       * to make sure `"node_modules"` will be ignored immediately with ignore pattern `"node_modules/"`.
  
       * There is a built-in cache about marked `File.Stat` in `glob`, so that we could not worry about the extra invocation of `this._mark()`
       */
      const marked = this._mark(abs);
  
      if (this[IGNORE](marked)) {
          return null;
      }
  
      return Sync.prototype._readdir.call(this, abs, inGlobStar);
  };
  
  
  module.exports = GlobSync;