index.js
function condenseify(file, options) {
  if (/\.json$/.test(file)) return through();

  var appendNewLine = true
    , regex = /^[ \t]+$/
    , isBlank = false
    , eol ='\n';

  options = options || {};

  function transform(line, encoding, next) {
    if (!line.length) {
      isBlank = true;
      return next();
    }

    line = line.toString();
    if (!options['keep-non-empty'] && regex.test(line)) return next();

    if (isBlank) {
      isBlank = false;
      this.push(eol);
    }
    appendNewLine = false;
    this.push(line + eol);
    next();
  }

  function flush(done) {
    if (appendNewLine) this.push(eol);
    done();
  }

  return pumpify(split(), through(transform, flush));
}
function condenseify(file, options) {
  if (/\.json$/.test(file)) return through();

  var appendNewLine = true
    , regex = /^[ \t]+$/
    , isBlank = false
    , eol ='\n';

  options = options || {};

  function transform(line, encoding, next) {
    if (!line.length) {
      isBlank = true;
      return next();
    }

    line = line.toString();
    if (!options['keep-non-empty'] && regex.test(line)) return next();

    if (isBlank) {
      isBlank = false;
      this.push(eol);
    }
    appendNewLine = false;
    this.push(line + eol);
    next();
  }

  function flush(done) {
    if (appendNewLine) this.push(eol);
    done();
  }

  return pumpify(split(), through(transform, flush));
}
function condenseify ( file , options ) { if ( / \.json$ / . test ( file ) ) return through ( ) ; var appendNewLine = true , regex = / ^[ \t]+$ / , isBlank = false , eol = '\n' ; options = options || { } ; function transform ( line , encoding , next ) { if ( ! line . length ) { isBlank = true ; return next ( ) ; } line = line . toString ( ) ; if ( ! options [ 'keep-non-empty' ] && regex . test ( line ) ) return next ( ) ; if ( isBlank ) { isBlank = false ; this . push ( eol ) ; } appendNewLine = false ; this . push ( line + eol ) ; next ( ) ; } function flush ( done ) { if ( appendNewLine ) this . push ( eol ) ; done ( ) ; } return pumpify ( split ( ) , through ( transform , flush ) ) ; }
Browserify transform to condense multiple blank lines
into a single blank line.

@param {String} file File name
@param {Object} [options] Options object
@returns {Stream} Transform stream
@api public
Browserify transform to condense multiple blank lines into a single blank line .