vinyl-map

Map vinyl files' contents as strings, so you can easily use existing code without needing yet another gulp plugin!
Essentially, with the hope of reducing the number of gulp plugins out there which are just doing this:

var through = require('through')
var uglify = require('uglify-js')

module.exports = function() {
  return through(function(file) {
    if (file.isNull()) return this.queue(file)
    if (file.isStream()) throw new Error('no support')

    file.contents = file.contents.toString()

    var minified = uglify.minify(file.contents, {
      fromString: true
    })

    file = file.clone()
    file.contents = new Buffer(minified.code)
    this.queue(file)
  })
}

Of course, sometimes that's fine too, but this might help save some complexity for when it's too much hassle. It also takes care of the differences between handling Buffer, Stream and null values for your file.contents.

Usage

Here's a simple example, using gulp:

var uglify = require('uglify-js')
var map = require('vinyl-map')
var gulp = require('gulp')

gulp.task('minify', function() {
  var minify = map(function(code, filename) {
    // file contents are handed
    // over as buffers
    code = code.toString()

    return uglify.minify(code, {
      fromString: true
    }).code
  })

  return gulp.src(['./index.js'])
    .pipe(minify)
    .pipe(gulp.dest('./dist'))
})

API ##

map(mapper(contents, filename)) ###

Returns a transform stream that takes vinyl files as input and spits out their modified copies as output.
mapper is a function which will be called once for each file, with two arguments:

• contents is a string or Buffer
• filename is the value of file.path, which should generally be the file's

absolute path. Might be convenient if you want to filter based on file extension etc.
The mapper function is expected to return a modified string value for the updated file contents. If nothing is returned, no modifications will be made to the file contents, but the output file will be cloned.

License ##

MIT. See LICENSE.md for details.