How to add separator to Concat options when using Usemin

group-concat, grunt-usemin, gruntjs

Solution

 concat: {
  options: {
    process: function (src, filepath) {
      if (filepath.split(/\./).pop() === 'js') {
        return src + ';\n';
      }
      return src;
    }
  }
}

Explanation of the process option link

The function splits the filepath into an Array with . (dot) as a separator. The pop() method from Array returns the last item of the array which should be the extension.

Problem

I am using Grunt-usemin. But the concatenated JS is not properly separated by ';'. How do I tell usemin to add the separator only for JS files but not CSS files? Currently, my usemin tasks look like this: ``` useminPrepare: { options: { dest: '<%= config.dist %>' }, html: '<%= config.app %>/index.html' }, // Performs rewrites based on rev and the useminPrepare configuration usemin: { options: { assetsDirs: ['<%= config.dist %>', '<%= config.dist %>/images'] }, concat: { separator: ';' }, html: ['<%= config.dist %>/{,*/}*.html'], css: ['<%= config.dist %>/styles/{,*/}*.css'] }, ``` Another use case would be wrapping each concatenated module in an IIFE, which requires this configuration, but should only be applied to *.js files: ``` concat: { options: { banner: ';(function () {', separator: '})(); (function () {', footer: '})();' } } ```

Original source