Outputs can have multiple assets

[43081j]

Similar to #350.

If an input has multiple output assets, an error will be thrown as the path will be an array rather than string.

This is because assetsByChunkName entries can be arrays:

https://webpack.js.org/api/stats/

But in karma webpack, we assume it is always a string:

https://github.com/webpack-contrib/karma-webpack/blob/d42c5418d93508c94d40031c42ca7107dd6f1a73/src/karma-webpack.js#L174

Using the source maps loader will cause this error as one js file will produce a map and a js asset

[michael-ciniawsky]

I see, would you mind trying to send PR to fix this? Checking for an {Array} and setting each item (entry) individually should be sufficient

[michael-ciniawsky]

cc @rynclark :)

[ryanclark]

Ill take a look later!

…

On Fri, 7 Sep 2018 at 20:05, Michael Ciniawsky ***@***.***> wrote: cc @rynclark <https://github.com/rynclark> :) — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#355 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AHjhvalpW0ChNj3jAyNuKZVUjXD7qF-oks5uYsN_gaJpZM4WfFnN> .

[michael-ciniawsky]

External sourcemaps currently don't seem work with karma-webpack according to the issue tracker, maybe we can fix that now aswell 🤔, but please let us focus on fixing the Path must be a string... issue first :) Should make it easier if we can ignore the .map file for now. Hopefully assetsByChunkName is deterministic 🙃

[GreenGremlin]

This also happens if a js file imports a css file. Possibly, only when using the extract-text-webpack-plugin.

[thijstriemstra]

fyi, also seeing this with 4.0.0 rc2:

08 09 2018 02:13:38.035:ERROR [karma]: TypeError: Path must be a string. Received [ 'spec/wavesurfer.spec.js', 'spec/wavesurfer.spec.js.map' ]
    at assertPath (path.js:28:11)
    at Object.join (path.js:1236:7)
    at Plugin.<anonymous> (/Users/foo/projects/wavesurfer.js/node_modules/karma-webpack/lib/karma-webpack.js:286:70)
    at Plugin.readFile (/Users/foo/projects/wavesurfer.js/node_modules/karma-webpack/lib/karma-webpack.js:305:5)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

[Bobsans]

+1
karma-webpack: ^4.0.0-rc.2

I use vue and mini-css-extract-plugin

10 09 2018 11:47:59.087:ERROR [karma]: TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received type object
    at assertPath (path.js:39:11)
    at Object.join (path.js:434:7)
    at Plugin.<anonymous> (D:\Python\proj\node_modules\karma-webpack\lib\karma-webpack.js:286:70)
    at Plugin.readFile (D:\Python\proj\node_modules\karma-webpack\lib\karma-webpack.js:305:5)
    at process._tickCallback (internal/process/next_tick.js:61:11)

and this.outputs is:

{
	"../test/components/Fa.spec.js":"..\\test\\components\\Fa.spec.f35f.js",
	"../test/components/Loader.spec.js":[
		"..\\test\\components\\Loader.spec.css",
		"..\\test\\components\\Loader.spec.f35f.js"
	],
	"../test/components/Url.spec.js":"..\\test\\components\\Url.spec.f35f.js"
}

[alabbas-ali]

Please check PR #357

[43081j]

Some regression or something happened with this...

With 3.0.5, test runs now do complete but some craziness goes on with multiple outputs.

If you have the sourcemaps loader enabled, for example, the resulting JS has two different sourcemaps so they fail to load correctly in chrome. Installing 3.0.0 makes it work again, so we've definitely introduced a bug somewhere.

foo;
// sourceMap;url=...
// sourceMap:url=...

This is the kind of thing we end up with.

[dulcetti]

Here with version 4.0.0-rc.2 I receive the error:

05 10 2018 11:21:11.759:ERROR [karma]: TypeError: Path must be a string. Received [ 'assets/css/app.style.6c4578761796562b94a9.min.css',
  'assets/css/app.style.6c4578761796562b94a9.min.css.map' ]

If I downgrade to 3.0.5, I recevei the message (node:14254) DeprecationWarning: Tapable.plugin is deprecated. Use new API on .hooks instead because version 4 of Webpack.

[didi0613]

The same thing happened here with version 4.0.0-rc.2
Error:

19 11 2018 14:16:25.525:ERROR [karma-server]: TypeError: Path must be a string. Received [ 'node_modules/electrode-archetype-react-component-dev/config/karma/entry.style.0ca30711e2d0162e57a8.css',
  'node_modules/electrode-archetype-react-component-dev/config/karma/entry.style.0ca30711e2d0162e57a8.css.map',
  'node_modules/electrode-archetype-react-component-dev/config/karma/entry.style.0ca30711e2d0162e57a8.css.map' ]

[ryanclark]

Does 4.0.0-rc.3 fix this for you?

[thijstriemstra]

No, I'm still seeing this #355 (comment) with rc3.

[matthieu-foucault]

@thijstriemstra : Can you use webpack-stats-plugin to output the assetsByChunkName object that triggers this error?

This issue seems only partially fixed

[thijstriemstra]

@matthieu-foucault resulting stats.json:

{
  "assetsByChunkName": {
    "videojs.record": [
      "css/videojs.record.min.css",
      "videojs.record.min.js",
      "videojs.record.min.js.map"
    ]
  }
}

[matthieu-foucault]

@thijstriemstra: I finally found some time to look into this, using your project (collab-project/videojs-record) to debug the issue.
What you are experiencing is a different issue, due to the fact that your webpack output.filename is a static name, which is a problem since you have more that a single entry point when testing with karma (each test file is an entry point), and they all end up being emmited to the same output.
I am still investigating as to why this now fails when it seems that it worked with beta.0, but that's a separate issue.
In the meantime, it seems that using [name].js as output.filename works around the issue.