2.9 Breaking change : default envDir now depends on alternative root

[Maniae]

Describe the bug

In 2.9, running vite command using an alternative root has vite looking for .env files in the alternative root directory.

The provide example can be fixed by adding a vite config file using this config : envDir: ../
I don't know if this is intended. Prior to 2.9, specifying an alternative root required specifying the vite.config file path if it was not located in the alternative folder, but didn't change the envDir default path. It now does and breaks projects using environment files not located in the alternative root folder.

Reproduction

https://stackblitz.com/edit/vitejs-vite-yvysne?file=package.json

System Info

any

Used Package Manager

npm

Logs

No response

Validations

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• The provided reproduction is a minimal reproducible example of the bug.

[bluwy]

Introduced in #6995. The docs initially mentioned that envDir defaults to the root, so if you change the root, it should load env files in that root directory only. So I don't think it's a breaking change.

[Maniae]

The way I see it is that this is a "breaking bug fix". Meaning that some projects may have been relying on the 2.8 behavior, event though it was the wrong one (I encountered the issue using .env file at the root project of a monorepo for instance).
Maybe a warning in the 2.9 release not could be enough