code: function doesFileExist(filePath) {
      if (!fileExistsCache.hasOwnProperty(filePath)) {
          fileExistsCache[filePath] = fs.existsSync(filePath);
      }
  
      return fileExistsCache[filePath];
  }
docs: Check to see if a particular file exists; cache results
  @param filePath
  @returns {*}