Next.js: Very unperformanced CaseSensitivePathsPlugin.

[Carduelis]

Bug report

Describe the bug

Very slow building time using npm run dev. CaseSensitivePathsPlugin takes a significant time to proceed.

Fast machine Core i7

Laptop Pentium

To Reproduce

Steps to reproduce the behavior, please provide code snippets or a repository:

1. Install SMP to detect the time
2. Wrap the config with new SpeedMeasurePlugin().wrap(config)
3. run npm run dev
4. See the screenshot above

Expected behavior

The first plugin took a lot of time to execute. Should not be a issue in every repo.

System information

• OS: Windows
• Version of Next.js: [ 8.0.3]

Additional context

The issue could be caused by aliases, but no time to check.

[Carduelis]

I've tested this plugin with { debug: true } and found that it's checking all of the modules including node_modules, so it does 2k+ reads every time

[CaseSensitivePathsPlugin] Total filesystem reads: 2566

[timneutkens]

8.0.4 doesn't have CaseSensitivePathsPlugin for this reason.

[timneutkens]

Speed measure plugin looks nice btw, hadn't seen it before 💯

[Carduelis]

Speed measure plugin looks nice btw, hadn't seen it before 💯

Could you include this measure, btw? The thing is when I wrap it, it breaks further work: next.js does not render anything and a browser does not open the app.

So, to measure I need to enable it, then disable to test is app loading ok. I think, the reason is SMP is not a plugin, but a config wrapper

[Carduelis]

@timneutkens
After installing next 8.0.4
I've caught the SMP output (via ScreenToGif), cause you clear the console output xD.

Thanks!

[timneutkens]

🙏