[v3.0.2] Plugin.prototype.readFile this.outputs[file] undefined because of OS path separator

[klmdb]

going from 2.x to 3.x, the code became dependent on os path separator:

2.0.13

middleware.fileSystem.readFile(path.join(os.tmpdir(), '_karma_webpack_', String(idx), file.replace(/\\/g, '/')), callback)
//...
var fileContents = middleware.fileSystem.readFileSync(path.join(os.tmpdir(), '_karma_webpack_', file.replace(/\\/g, '/')))

3.0.2

middleware.fileSystem.readFile(path.join(os.tmpdir(), '_karma_webpack_', String(idx), this.outputs[file]), callback)
//...
var fileContents = middleware.fileSystem.readFileSync(path.join(os.tmpdir(), '_karma_webpack_', this.outputs[file]))

this.outputs[file] should be this.outputs[file.replace(/\\/g, '/')]

[michael-ciniawsky]

Could you try with path.posix.join or a small helper

const normalize = (file) => file.split(path.sep).join('/')
...
... this.outputs[normalize(file)] ...

I'm assuming your are on windows, right? Otherwise please elaborate in more detail what doesn't work please (Actual/Expected)

[klmdb]

Yes I am on Windows.

[ghost]

Running karma-webpack on Windows results in the following error message on 3.0.2:

ERROR [karma]: [TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received type undefined

Running on 2.0.0 works.
The problem seems to be that this.outputs is indexed with paths using forward slash separators while backslash separators are not replaced in the indexing string. This means every reference to files in different directories on windows-machines throws an error.

[Javi]

Can confirm, just got bit by this on Windows and making paths like [`folder${path.delimiter}file.js`] makes it work.

[nomve]

I don't run Windows but still have the same issue

https://github.com/webpack-contrib/karma-webpack/blob/d2f5a538d864e7b1f4bb431324de67be1ccbb51d/src/karma-webpack.js#L238

this.outputs is just an empty {}. the only place I see it get written is here
https://github.com/webpack-contrib/karma-webpack/blob/d2f5a538d864e7b1f4bb431324de67be1ccbb51d/src/karma-webpack.js#L131

but this runs later.

[nomve]

downgrading to 3.0.0 also works for me

[michael-ciniawsky]

Fixed by #353, released in v3.0.3 🎉