Error in ModuleConcatenationPlugin: The export has no internal name

[jeffijoe]

Do you want to request a feature or report a bug?

Report a Bug. 🐛 😱

What is the current behavior?

I am getting the following error when using ModuleConcatenationPlugin:

Error: The export "__WEBPACK_MODULE_DEFAULT_EXPORT__" in "./src/client/stores/index.js" has no internal name
    →      at getFinalName (my-app/node_modules/webpack/lib/optimize/ConcatenatedModule.js:29:10)
    →      at info.globalScope.through.forEach.reference (my-app/node_modules/webpack/lib/optimize/ConcatenatedModule.js:395:24)
    →      at Array.forEach (native)
    →      at modulesWithInfo.forEach.info (my-app/node_modules/webpack/lib/optimize/ConcatenatedModule.js:383:29)
    →      at Array.forEach (native)
    →      at ConcatenatedModule.source (my-app/node_modules/webpack/lib/optimize/ConcatenatedModule.js:382:19)
    →      at ModuleTemplate.render (my-app/node_modules/webpack/lib/ModuleTemplate.js:14:31)
    →      at my-app/node_modules/webpack/lib/Template.js:110:28
    →      at Function.from (native)
    →      at Chunk.mapModules (my-app/node_modules/webpack/lib/Chunk.js:163:16)
    →      at HotUpdateChunkTemplate.renderChunkModules (my-app/node_modules/webpack/lib/Template.js:107:26)
    →      at HotUpdateChunkTemplate.render (my-app/node_modules/webpack/lib/HotUpdateChunkTemplate.js:20:30)
    →      at Compilation.<anonymous> (my-app/node_modules/webpack/lib/HotModuleReplacementPlugin.js:122:46)
    →      at Array.forEach (native)
    →      at Compilation.<anonymous> (my-app/node_modules/webpack/lib/HotModuleReplacementPlugin.js:111:37)
    →      at Compilation.applyPlugins1 (my-app/node_modules/tapable/lib/Tapable.js:75:14)
    →      at sealPart2 (my-app/node_modules/webpack/lib/Compilation.js:631:9)
    →      at next (my-app/node_modules/tapable/lib/Tapable.js:138:11)
    →      at Compilation.compilation.plugin (my-app/node_modules/webpack/lib/ProgressPlugin.js:111:6)
    →      at Compilation.applyPluginsAsyncSeries (my-app/node_modules/tapable/lib/Tapable.js:142:13)
    →      at Compilation.seal (my-app/node_modules/webpack/lib/Compilation.js:579:8)
    →      at applyPluginsParallel.err (my-app/node_modules/webpack/lib/Compiler.js:514:17)
    →      at my-app/node_modules/tapable/lib/Tapable.js:225:11
    →      at _addModuleChain (my-app/node_modules/webpack/lib/Compilation.js:481:11)
    →      at processModuleDependencies.err (my-app/node_modules/webpack/lib/Compilation.js:452:13)
    →      at _combinedTickCallback (internal/process/next_tick.js:95:7)
    →      at process._tickDomainCallback (internal/process/next_tick.js:198:9)

If the current behavior is a bug, please provide the steps to reproduce.

The file that the error is mentioning looks something like this:

class RootStore {
  // ...
}

const rootStore = new RootStore()
if (process.env.NODE_ENV !== 'production') {
  window.rootStore = rootStore
}

export default rootStore

What is the expected behavior?

No error should be thrown.

Please mention other relevant information such as the browser version, Node.js version, webpack version and Operating System.

• Node v8.1.2
• Webpack 3.3.0
• macOS Sierra

[nifgraup]

I got this as well and fixed by changing a default export to named export. Does this have something to do with circular dependencies?

[jeffijoe]

I fixed it by doing the same, but I'd still say it's a bug, no?

[nifgraup]

Yes, it's a bug.

[sokra]

Do you have a repro repo for me?

[jeffijoe]

@sokra I'm unable to reproduce in a clean app, sorry.

@nifgraup Do you think you are able to reproduce it in a create-react-app app? I've tried myself but not sure what makes it work there and not in my bigger project.

[nodkz]

@jeffijoe same thing - cannot reproduce simple example. It seems that babel transformations did some magic that not work with webpack ModuleConcatenationPlugin.

PS. BTW, did you use react-lodable?

[jeffijoe]

@nodkz I haven't used code splitting since webpack 1, had random runtime failures 2/10 times cause of it.

[nifgraup]

Minimal repro, use with babel-loader:
entry point a.js:

import b from "./b.js";
export default {};

b.js:

import a from "./a.js";
<a />; // JSX syntax, comment out and error goes away
export default {};

Not a regression, error was there as well in v3.0.0-rc.0.

[joeybaker]

I'm seeing a similar problem, let me know if I should open a new issue

// file.js
import fetchPonyfill from 'fetch-ponyfill'
const useGlobal = () => …
export const { fetch } = useGlobal() ? global : fetchPonyfill()

When ModuleConcatenationPlugin is active, this results in:

ERROR in chunk main [entry]
bundle.js
The export "fetch" in "./file.js" has no internal name

[sokra]

Try with latest version, if it's still an issue, create a repro case and open a new issue.

[bf]

This bug is still an issue.