Ignore array of files with Grunt

Question

If I have an array of files in my Gruntfile like so:

var jsFiles = [
  'src/js/abc.js',
  'src/js/def.js'
]

How can I exclude each file in this array without having to prepend ! to each file? This pattern doesn't seem to work for me:

!jsFiles

I would also love to be able to do !<%= project.jsFiles %> where <%= project.jsFiles %> is an array of files.

There are a number of similar questions on Stack Overflow but not one that addresses ignoring an array of files, from what I can see.

Answer 1

Negate array of files:

If your want to negate a list of files, like this:

var jsFiles = [
  'src/js/abc.js',
  'src/js/def.js'
];

You can create a function to add the "!":

function addErase(jsFiles){
  var arr = [];
  jsFiles.forEach(function(element){
    arr.push("!" + element);
  });
  return arr;
}

Then you can transform your array:

var jsFileErase = addErase(jsFiles);
//   ['!src/js/abc.js',
//   '!src/js/abc.js']

If you want to put the list in the package.json:

Package.json:

{
  "name": "foo",
  "version": "0.0.1",
  "jsFiles":[
    'src/js/abc.js',
    'src/js/def.js'
  ],
  ...

Inside Gruntfile.js:

var project = require('./package.json');
var jsFiles = project.jsFiles;

Then you can negate all the files with the function addErase

Negate all element inside a folder:

If you want to negate all the elements inside a folder, you need to put "!" before the path and "/**/*" at the end of the path:

Example:

var jsFile = '!src/js/**/*'