copy-webpack-plugin higher than 6.2.1 causes builds to fail

[Razviar]

Preflight Checklist

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.
• I have searched the issue tracker for a bug that matches the one I want to file, without success.

Issue Details

• Electron Forge Version:
  • 6.0.0-beta.54
• Electron Version:
  • 12.0.0
• Operating System:
  • Windows 10
• Last Known Working Electron Forge version::
  • N/a

Expected Behavior

successful build.

Actual Behavior

An unhandled error has occurred inside Forge:
compilation.getCache is not a function
TypeError: compilation.getCache is not a function
at D:\mtgap\node_modules\copy-webpack-plugin\dist\index.js:473:33
at SyncHook.eval (eval at create (D:\mtgap\node_modules\tapable\lib\HookCodeFactory.js:19:10), :7:1)
at SyncHook.lazyCompileHook (D:\mtgap\node_modules\tapable\lib\Hook.js:154:20)
at Compiler.newCompilation (D:\mtgap\node_modules\webpack\lib\Compiler.js:630:30)
at D:\mtgap\node_modules\webpack\lib\Compiler.js:667:29
at AsyncSeriesHook.eval [as callAsync] (eval at create (D:\mtgap\node_modules\tapable\lib\HookCodeFactory.js:33:10), :6:1)
at AsyncSeriesHook.lazyCompileHook (D:\mtgap\node_modules\tapable\lib\Hook.js:154:20)
at Compiler.compile (D:\mtgap\node_modules\webpack\lib\Compiler.js:662:28)
at D:\mtgap\node_modules\webpack\lib\Watching.js:77:18
at AsyncSeriesHook.eval [as callAsync] (eval at create (D:\mtgap\node_modules\tapable\lib\HookCodeFactory.js:33:10), :24:1)
at AsyncSeriesHook.lazyCompileHook (D:\mtgap\node_modules\tapable\lib\Hook.js:154:20)
at Watching._go (D:\mtgap\node_modules\webpack\lib\Watching.js:41:32)
at D:\mtgap\node_modules\webpack\lib\Watching.js:33:9
at Compiler.readRecords (D:\mtgap\node_modules\webpack\lib\Compiler.js:529:11)
at new Watching (D:\mtgap\node_modules\webpack\lib\Watching.js:30:17)
at Compiler.watch (D:\mtgap\node_modules\webpack\lib\Compiler.js:244:10)

To Reproduce

Try to build any app with copy-webpack-plugin version higher than 6.2.1

[Eli-Black-Work]

Are you using Webpack 5?

[Eli-Black-Work]

Also, see webpack-contrib/copy-webpack-plugin#575 🙂

[Razviar]

@Bosch-Eli-Black the thing is, forge is using webpack 4 as it appears, and it needs update

[Eli-Black-Work]

Ya, that's what I think, too. I've just opened a feature request for Webpack 5 support: #2208 🙂

[malept]

The webpack plugin uses Webpack 5 as of Forge beta 56.