Grunt: How to build the files object dynamically

Question

I must be missing something very simple here. I\'m trying to write a function task that deals with files. The Grunt API docs mention that you can [Build the files object dynamic

Answer 1

Here is the workaround I found to dynamically build filesets for Grunt tasks:

uglify: {
    app: {
        files: [{
            src: '{<%= _prefixSrc(pkg.target, pkg.resources.js) %>}', // Note the brackets!
            dest: '<%= pkg.target %>min/<%= pkg.name %>.min.js'
        }]
    }
},
_prefixSrc: function(prefix, files) {
    return files.map(function(file){
        return prefix + file;
    });
},

See also this issue/feature request on GitHub and feel free to comment it if you find it useful: https://github.com/gruntjs/grunt/issues/1307

Answer 2

You can use rename function to change file name is files object like below...

build: {
  files: [{
    expand: true,
    cwd: 'src',
    src: ['**/*.js'],
    dest: 'dist',
    rename: function(dest, src) {
      /* 
         rename logic
         you will have access to src and dest name and can return desirect name from this function.
      */
      return src+123;
    }
 }]
}