Creating a new source file results in an unhelpful "This rust file does not belong to a loaded cargo project" notification

[Zalathar]

rust-analyzer version: 0.3.1463-standalone (2365762 2023-04-02)

Steps to reproduce:

• In an existing VSCode project, right-click on your source directory and choose “New File...”
• Enter a file name (e.g. foo.rs)
• Open the file

Actual behaviour:

When the file is opened, a popup immediately appears warning that:

This rust file does not belong to a loaded cargo project. It looks like it might belong to the workspace at file:///path/to/Cargo.toml, do you want to add it to the linked Projects?
[Yes] [No] [Don't show this again]

This is pretty confusing, since I'm about to add the file to my project with the “Insert mod foo;” quick-fix, and none of the options provided seem to have anything to do with that.

Also, the Cargo.toml file mentioned in the popup is the one that RA has already loaded, so trying to load it more isn't going to help.

[Zalathar]

The prompt seems to come from #14366, which is trying to be helpful, but in this particular (very common) case it ends up being misguided.

[dporr]

I was facing this same issue since today and this affected auto-completion too. Also, clicking the pop-up options doesn't solve the problem and makes it more confusing.

I fixed it adding pub mod foo; to my lib.rs as mentioned in the original issue.

[Al3xDaniels]

Was this resolved? I am experiencing the same issue and not seeing a fix.

[Veykril]

It should be fixed, what is your rust-analyzer version?

[Zalathar]

FWIW, it seems to be fixed for me:

rust-analyzer version: 0.3.1481-standalone (bab80da 2023-04-16)

[voloshink]

still ran into this issue today, seems to be tied to a specific file name for some reason

[yeousunn]

same issue today,
The moment I open a file or begin typing, a notification window pops up.
rust-analyzer version v0.3.1533 and is installed for wsl

[zhongqc]

same issue today
rust-analyzer version v0.3.1541 for MacOS 12.6

[josdirksen]

Same here: OSX with rust-analyzer plugin. Release version (v0.3.1566) as well as Pre-release version (v0.4.1565)

Well seems to be caused by creating a subfolder to hold a module, and not having defined the mod.rs yet. After adding that it works.