code duplication

[giulianozorzi]

Hello,
I was redirected here by a member of the grunt-fixmyjs team.
I'm using fixmyjs 1.0.3 grunt-fixmyjs version 0.3.0 with the grunt 1.0.1 and grunt-vli 1.2.0, all installed by npm

my grunt task is the following:

fixmyjs: {
options: {
config: '.jshintrc',
indentpref: 'spaces'
},
test: {
files: [
{
expand: true,
cwd: 'static/js',
src: ['*/.js'],
dest: 'static/js/',
ext: '.js'
}
]
}
},
Sometimes (I could not find a way to replicate I get duplicated code (ie if the source file contains

var a = true;
I end up with

var a = true;
var a = true;
the tasks I'm running are in order

fixmyjs
jshint
concat
uglify
Is there a way to determine what causes this and fix this behaviour ? As now I've changed the task so the ext is changed to

ext: '.fixed.js'

but I'd really like to fix my js files for good :)

thanks !