Replace not working with multiple files.

[ZeroThe2nd]

Having my copy object written for multiple files as in the docs, but adding the process option, does not work as it should. The files get copied, but not modified. When not using the files but defining a single file as per the docs, the copy and replace works, but for one file only.

I'm running the folloing:

• grunt-contrib-copy v1.0.0
• Linux Mint 18
• grunt-cli v1.2.0
• grunt v1.0.1
• npm v5.6.0
• nodejs v8.9.3

Copy section from gruntfile.js

copy   : {
    main : {
        files : [
            {                src     : 'assets/js/app.js',
                dest    : 'dist/assets/js/app.build.js',
                options : {
                    process : function(content, srcpath) {
                        return content.replace(/(\.css')/g, '.min.css\'');
                    },
                },
            },
            {
                src     : 'index.html',
                dest    : 'dist/index.html',
                options : {
                    process : function(content, srcpath) {
                        return content.replace('assets/js/app.js', 'assets/js/app.min.js');
                    },
                },
            },
            {
                src  : 'assets/js/Helper.js',
                dest : 'dist/assets/js/Helper.build.js',
            },
            {
                expand : true,
                src    : [
                    '/assets/audio/**',
                    '/assets/icons/**',
                    '/assets/images/**',
                ],
                dest   : 'dist/assets',
                filter : 'isFile',
            },
        ],
    },
},