`Duration::from_mins` and `Duration::from_hours` where [recently
stabilized](https://github.com/rust-lang/rust/issues/140881) in Rust
1.91.0.
In our codebase we often times have things like
```rust
Duration::from_secs(5 * 60);
// Since Rust 1.91.0 one can use
Duration::from_mins(5)
```
During the Rust 1.91.0 bump I noticed we can finally switch to
`Duration::from_mins(5)`, but many users might not be aware of this. I
started manually updating the places, but halfway through I figured
"Can't a lint do this for me?", so I added exactly that in this PR. It
does it for all stabilized `from_XXX` time units.
changelog: Add new [`duration_suboptimal_units`] lint
Closesrust-lang/rust-clippy#16335
This resulted in the following error for me:
error[E0464]: multiple candidates for `rlib` dependency `rustc_literal_escaper` found
--> clippy_dev/src/lib.rs:25:1
|
25 | extern crate rustc_literal_escaper;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: candidate #1: /home/pkrones/.rustup/toolchains/nightly-2025-12-25-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_literal_escaper-4f30574e01c3dad1.rlib
= note: candidate #2: /home/pkrones/.rustup/toolchains/nightly-2025-12-25-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/librustc_literal_escaper-c8a0e29ad1040cee.rmeta
Other tools in the Rust repo also take that as an explicit dependency, like rust-analyzer or lint-docs.
This stops using `cargo fmt` and instead calls rustfmt directly with the
list of all files.
All `cargo fmt` does is find the crate roots and passes the edition from
`cargo.toml`. Since the edition is set in `rustfmt.toml` for the test
files and we're already iterating through all the files this is not
needed.
`--skip-children` is used since we already pass all the files, so the
automatic detection isn't buying us anything other than running slower.
~Second commit~ (part of the first commit now) is a change to only use
the `ignore` option in `rustfmt.toml` rather than having a way in `cargo
dev fmt` to ignore files.
r? @samueltardieu
changelog: none
