1. module gulp-concat
   1. function gulp-concat (file, opt)

module gulp-concat

function gulp-concat (file, opt)

• description and source-code

  gulp-concat = function (file, opt) {
    if (!file) {
      throw new Error('gulp-concat: Missing file option');
    }
    opt = opt || {};
  
    // to preserve existing |undefined| behaviour and to introduce |newLine: ""| for binaries
    if (typeof opt.newLine !== 'string') {
      opt.newLine = '\n';
    }
  
    var isUsingSourceMaps = false;
    var latestFile;
    var latestMod;
    var fileName;
    var concat;
  
    if (typeof file === 'string') {
      fileName = file;
    } else if (typeof file.path === 'string') {
      fileName = path.basename(file.path);
    } else {
      throw new Error('gulp-concat: Missing path in file options');
    }
  
    function bufferContents(file, enc, cb) {
      // ignore empty files
      if (file.isNull()) {
        cb();
        return;
      }
  
      // we don't do streams (yet)
      if (file.isStream()) {
        this.emit('error', new Error('gulp-concat: Streaming not supported'));
        cb();
        return;
      }
  
      // enable sourcemap support for concat
      // if a sourcemap initialized file comes in
      if (file.sourceMap && isUsingSourceMaps === false) {
        isUsingSourceMaps = true;
      }
  
      // set latest file if not already set,
      // or if the current file was modified more recently.
      if (!latestMod || file.stat && file.stat.mtime > latestMod) {
        latestFile = file;
        latestMod = file.stat && file.stat.mtime;
      }
  
      // construct concat instance
      if (!concat) {
        concat = new Concat(isUsingSourceMaps, fileName, opt.newLine);
      }
  
      // add file to concat instance
      concat.add(file.relative, file.contents, file.sourceMap);
      cb();
    }
  
    function endStream(cb) {
      // no files passed in, no file goes out
      if (!latestFile || !concat) {
        cb();
        return;
      }
  
      var joinedFile;
  
      // if file opt was a file path
      // clone everything from the latest file
      if (typeof file === 'string') {
        joinedFile = latestFile.clone({contents: false});
        joinedFile.path = path.join(latestFile.base, file);
      } else {
        joinedFile = new File(file);
      }
  
      joinedFile.contents = concat.content;
  
      if (concat.sourceMapping) {
        joinedFile.sourceMap = JSON.parse(concat.sourceMap);
      }
  
      this.push(joinedFile);
      cb();
    }
  
    return through.obj(bufferContents, endStream);
  }

• example usage

  n/a