How can I skip a grunt task if a directory is empty

Question

I\'m using grunt-contrib\'s concat and uglify modules to process some javascript. Currently if src/js/ is empty, they will still create a

Answer 1

Maybe this is just a more up-to-date answer as the others are more than a year old, but you don't need a plugin for this; you can use grunt.file.expand to test if files matching a certain globbing pattern exist.

Update of @Kosmotaur's answer (path is just hard-code here though for simplicity):

grunt.registerTask('build_js', function(){
  // if any file matches the glob pattern
  if (grunt.file.expand("subdir/**/*.js").length) { /** new bit here **/ 
    // if so, run the task chain
    grunt.task.run([
        'trimtrailingspaces:js'
      , 'concat:js'
      , 'uglify:yomama'
    ]);
  }
});