Clippy has no --color option

[mvtec-bergdolll]

Similar to other cargo tooling and cargo itself there should be a --color=always/never option for clippy.

I have situation where I'd like to pipe clippy into other programs and preserve the colors. But I see no way of achieving that.

Example bash: cargo test -- --color=always |& less preserves colors but cargo clippy -- --color=always |& less fails and just cargo clippy |& less strips colors.

@ rustbot label +C-enhancement

[kwi-dk]

Not sure if time has overtaken this ticket, but at least as of

cargo 1.61.0 (a028ae4 2022-04-29)
clippy 0.1.61 (fe5b13d 2022-05-18)

I get the following results:

1. cargo --color always clippy → color option is ignored.
2. cargo clippy --color always → color option is respected and colors are preserved even when redirecting.
3. cargo clippy -- --color always → error: cannot specify the `--color` option with `--json`

So (now, at least) there is a color option, you just have to place it exactly right.

(3) seems like acceptable behavior (once you pass --, you've voluntarily broken the abstraction provided by cargo, and it's on you to ensure your arguments are compatible with what cargo is passing), but (1) seems like a bug. (For comparison, cargo check supports the color argument both before and after check.)

[Sindisil]

As of

cargo 1.76.0-nightly (623b78849 2023-12-02)
clippy 0.1.76 (9fad685 2023-12-03)

it doesn't appear to me that clippy respects "--color never", at least not in some cases. It also doesn't respect the CARGO_TERM_COLOR environment variable, at least in some cases (e.g., "cargo clippy --help" shows color regardless of if/where I place "--color never", nor does it respect my setting of CARGO_TERM_COLOR to never.