Update Rust toolchain version?

[smoelius]

Copied from rust-lang/rust-clippy#11490:

I am using the clippy_utils crate for developing dylint programs. I need to add the clippy_utils that matches the toolchain I am using (currently 1.74.0-nightly) to my Cargo.toml as a lib dependency. I can’t add this dependency from the rust repository because the repository is too big, so I have to use a version from the rust-clippy repository.

Originally posted by @EFanZh in rust-lang/rust-clippy#11490 (comment)

[smoelius]

I need to add the clippy_utils that matches the toolchain I am using (currently 1.74.0-nightly)

Sorry, does that mean you're using the latest nightly?

We recommend pinning to a specific date, to avoid the kinds of problems you seem to be describing (example).

Is there a reason why that strategy wouldn't work for you? (Or have I misunderstood your problem?)

[EFanZh]

No, we do pin the Rust toolchain version, but the version we need have to be at least nightly-2023-09-10. Because there are some compiler features that our project requires, that have just been added to the compiler.

[smoelius]

OK. (Sorry for misunderstanding.)

I can see three possible courses of action.

1. Wait until the next Rust-Clippy sync. Like Alexandoo said, they happen every two weeks, and here was the last one: Rustup rust-lang/rust-clippy#11469 So I would expect the next to be sometime mid next week.

2. Fork Clippy, apply the updates yourself, and use that fork (at least until Clippy is updated).

3. To my amazement(!), you can use the Rust repo as the source for clippy_utils, e.g.:

clippy_utils = { git = "https://github.com/rust-lang/rust", rev = "8ed4537d7" }

That commit came from rustc --version, e.g.:

$ rustc --version
rustc 1.74.0-nightly (8ed4537d7 2023-09-09)

Note that it takes a looong time for Cargo to download Rust as a dependency. But it's a onetime cost, and it's probably quicker than applying the updates yourself as in option 2.

EDIT: "looong time" = tens of minutes, in my case.

[EFanZh]

I think I’ll wait 7 days for the next sync. Thank you for your help!