Next.js should enforce case sensitivity even if OS doesn't

[Timer]

Bug report

Describe the bug

User churn due to:

Module not found: Can't resolve 'next/Head' in '/zeit/628124c9/pages'

To Reproduce

Import next/Head on a case insensitive filesystem and it will work.
Deploy to a sensitive one, it'll fail to build.

Expected behavior

Next.js should never of allowed the build in the first place and suggested the user fix the case sensitivity issue.

[Janpot]

this PR won't fix this exact case, but it seems related.
🤔 This may be solvable with with a linter as well. Or with case-sensitive-paths-webpack-plugin

[Timer]

Switching this from a bug to feature request due to your PR landing @Janpot 🙏

[CallmeHongmaybe]

I was having the same kind of error:
Module not found: Can't resolve '../../../components/Trends' in '/vercel/3e42d29f/pages/country/[category]'

Not sure what I actually did wrong here, even though I'm pretty sure I used correct casing for the component file.

[utiq]

@CallmeHongmaybe Same issue, how did you solve it?

[sphilee]

I think this could be useful.

isEnvDevelopment && new CaseSensitivePathsPlugin(),

https://github.com/facebook/create-react-app/blob/master/packages/react-scripts/config/webpack.config.js#L660

[CallmeHongmaybe]

@utiq I actually haven't solved this yet.

[CallmeHongmaybe]

So I'm just gonna put the CaseSensitivePathsPlugin somewhere in next.config.js amirite

[utiq]

I solved my problem, in my case it was my git configuration, I run this:
git config --global core.ignorecase false

[CallmeHongmaybe]

@utiq Thanks a lot for the code. I actually took out the --global flag and it worked perfectly.

[cbdeveloper]

Can I get an official recommendation whether we should keep git config ignoreCase as true or false in our projects?

My app build was successful on my local environment (Windows) but was failing in Vercel.

I was getting:

Failed to compile Type error: Cannot find module '../../pages/error/ErrorPage' or its corresponding type declarations.

Later I've found out that it was because I'd renamed that path from pages/Error to pages/error. And my git ignoreCase was set to true (I've never chosen that, but I guess git init made that choice for me).

To fix it, I changed git config ignoreCase to false. After that, git created a new untracked file for my ErrorPage module, so I committed that. And then it still wouldn't build, because now I was getting a new error:

Type error: Already included file name '/vercel/path0/app/pages/error/ErrorPage.tsx' differs from file name '/vercel/path0/app/pages/Error/ErrorPage.tsx' only in casing.

So I had to change it to a brand new path name like: pages/error-new/ErrorPage.tsx.

And only then I was able to build it successfully on Vercel.

Later I was able to go back to my desired path name as pages/error/ErrorPage.

Maybe my git config ignoreCase should be set to false from the get go? What do you guys think?

[vltansky]

Had the same problem.
git config core.ignorecase false (not global) fixed it for me. Thanks @CallmeHongmaybe

[github-actions]

Please verify that your issue can be recreated with next@canary.

Why was this issue marked with the please verify canary label?

We noticed the provided reproduction was using an older version of Next.js, instead of canary.

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[balazsorban44]

This issue has been automatically closed because it wasn't verified against next@canary. If you think it was closed by accident, please leave a comment. If you are running into a similar issue, please open a new issue with a reproduction. Thank you.

[github-actions]

This closed issue has been automatically locked because it had no new activity for a month. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.