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

With this plugin:

https://www.npmjs.org/package/grunt-file-exists

You can check file existence. (I didn't try, but the source looks like supporting grunt expands. (*, ** ...)

For example like this::

grunt.initConfig({
  fileExists: {
    scripts: ['a.js', 'b.js']
  },
});

grunt.registerTask('conditionaltask', [
    'fileExists',
    'maintask',
]);

But maybe if the file doesn't exist it will fail with error instead of simple skip. (I didn't test it.)

If this is a problem you can modify a bit the source of this plugin to run the related task if the file exists:

The config:

grunt.initConfig({
  fileExists: {
    scripts: ['a.js', 'b.js'],
    options: {tasks: ['maintask']}
  },
});

grunt.registerTask('conditionaltask', [
    'fileExists',
]);

And you should add this:

grunt.task.run(options.tasks);

In this file:

https://github.com/alexeiskachykhin/grunt-file-exists/blob/master/tasks/fileExists.js

after this line:

grunt.log.ok();