Warning: path must be a string Use --force to continue.

[slavede]

I have grunt task for babel as it's described on Babel official page:

babel : {
  options: {
      sourceMap: true
    },
  dist : {
    files : {
      'app/scripts/controllers/target-babel.js' : 'app/scripts/controllers/src.js'  
    }
  }
},

After running grunt babel I get:

Running "babel:dist" (babel) task
Warning: path must be a string Use --force to continue.

Aborted due to warnings.

[mauvm]

I'm having the same issue. How did you solve this?

[slavede]

Hey, I closed this as invalid since I did stupid thing...path was wrong :), double check that :)

[mauvm]

Oops. You are absolutely right. I switched the source and dest paths. 😁

[zanesterling]

It would be nice if the error message were more useful.

[Vulle]

I see that this case is closed but I would appreciate some help.
I'm getting:
Running "watch" task
Waiting...
Warning: Path must be a string. Received undefined

I haven't changed any paths. So I don't understand why it could happen.
Thanks!

[mauvm]

@Vulle Then it's probably a change in package version. What does your Gruntfile and package.json look like?

[Vulle]

@mauvm
I installed grunt-contrib-watch and it worked with grunt serve.. The "watch" worked and then I got problem with grunt build, similar problem.
So I reinstalled my project, now it works.

Thanks for answering!

[at-loctd]

my code do work well
files: { 'build/js/es6_demo.js': 'dev/js/es6.js'}