@tailwindcss/vite v4.0.1 not working Cannot read properties of undefined (reading 'includes')

[peterhirn]

What version of Tailwind CSS are you using?

v4.0.1

What build tool (or framework if it abstracts the build tool) are you using?

@tailwindcss/vite

What version of Node.js are you using?

v23.6.1

What browser are you using?

All

What operating system are you using?

Linux

Reproduction URL

I understand that reproduction is required, I just don't have the time right now, sorry. Since this issue is extremely obvious I hope you can do without.

Describe your issue

TypeError: Cannot read properties of undefined (reading 'includes')
    at m (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/@tailwindcss+vite@4.0.1_vite@6.0.11_@types+node@22.12.0_jiti@2.4.2_lightningcss@1.29.1_terser@5.37.0_/node_modules/@tailwindcss/vite/dist/index.mjs:1:1599)
    at transformIndexHtml (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/@tailwindcss+vite@4.0.1_vite@6.0.11_@types+node@22.12.0_jiti@2.4.2_lightningcss@1.29.1_terser@5.37.0_/node_modules/@tailwindcss/vite/dist/index.mjs:1:3059)
    at getVitePluginAssets (/home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/vinxi@0.5.1_@types+node@22.12.0_ioredis@5.4.1_jiti@2.4.2_lightningcss@1.29.1_terser@5.37.0_typescript@5.7.3/node_modules/vinxi/lib/manifest/dev-server-manifest.js:186:39)
    at Object.assets (/home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/vinxi@0.5.1_@types+node@22.12.0_ioredis@5.4.1_jiti@2.4.2_lightningcss@1.29.1_terser@5.37.0_typescript@5.7.3/node_modules/vinxi/lib/manifest/dev-server-manifest.js:234:26)
    at async createPageEvent (/home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/@solidjs+start@1.0.11_@testing-library+jest-dom@6.6.3_solid-js@1.9.4_vinxi@0.5.1_@types+node@_fvmhuimud5ps5vjvpmm3ezrqsi/node_modules/@solidjs/start/dist/server/pageEvent.js:34:17)
    at async eval (/home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/@solidjs+start@1.0.11_@testing-library+jest-dom@6.6.3_solid-js@1.9.4_vinxi@0.5.1_@types+node@_fvmhuimud5ps5vjvpmm3ezrqsi/node_modules/@solidjs/start/dist/server/handler.js:37:25)
    at async _callHandler (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/h3@1.13.0/node_modules/h3/dist/index.mjs:1837:16)
    at async _callHandler (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/h3@1.13.0/node_modules/h3/dist/index.mjs:1837:16)
    at async _callHandler (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/h3@1.13.0/node_modules/h3/dist/index.mjs:1837:16)
    at async file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/h3@1.13.0/node_modules/h3/dist/index.mjs:1978:19
    at async Object.callAsync (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/unctx@2.4.0/node_modules/unctx/dist/index.mjs:72:16)
    at async Server.toNodeHandle (file:///home/peter/Projects/phi-ag/rvt-app/node_modules/.pnpm/h3@1.13.0/node_modules/h3/dist/index.mjs:2270:7)

Since there was only a single commit between 4.0 and 4.0.1 I assume the issue is this:

https://github.com/tailwindlabs/tailwindcss/pull/16005/files#diff-00d01a2d38f5f4253651cf9811eab1182c96f0307e78c567b803416e24b98165R70

[philipp-spiess]

@peterhirn Hey! Sorry for the crash.

Can you maybe share your dependency list so we can try to get a repro going? We can make this field nullable so it doesn't crash but based on the Vite typings, id should always be present so I think this might be either an older version of Vite or a Vite plugin we haven't considered. In either case it would be good to have a test case for this.

[peterhirn]

Hey, thanks for looking into this. ❤️

This is one of the projects which fail at runtime (ie. pnpm dev): https://github.com/phi-ag/rvt-app

[philipp-spiess]

Seems like this happens with a SolidStart app. For some reason when using that we get a transformIndexHtml callback for a HTML file with the content / and no path whatsoever. Will fix and add an integration test. Odd one for sure! Thanks for the report.

Only happens in dev builds from what I can see too 🙈

[peterhirn]

Thanks! SolidStart and TanStack Start are based on https://github.com/nksaraf/vinxi which is ... special 😁

[philipp-spiess]

Just a quick head-sup that this will be fixed in the next release. You can try to use the insiders build which will have the fix available already:

npm install tailwindcss@insiders @tailwindcss/vite@insiders

[peterhirn]

Great, thanks. I'm currently blocking the renovate automerge for v4.0.1 since v4.0 works fine.

Another thing I didn't mention yet: file auto-detection doesn't seem to work with SolidStart, I had to go back to explicit config: https://github.com/phi-ag/rvt-app/blob/main/tailwind.config.js#L7

I'll re-test this with the next release and open a new issue if necessary.

[philipp-spiess]

Sounds good! Yeah I did find another issue with SolidStart that was causing the dev server to not work as expected. Let me know if there are still issues though!

[Constantor]

Just a quick head-sup that this will be fixed in the next release. You can try to use the insiders build which will have the fix available already:

npm install tailwindcss@insiders @tailwindcss/vite@insiders

Thank you very much for such a prompt fix!