[Feature Request]: Lint Configuration inlined in the attribute macro.

[GilShoshan94]

Description

Hi,

Awsome tool that help me to be proeficient in Rust.

I am trying to use some of the new lint such as clippy::cognitive_complexity.
I see it can be configured by cognitive-complexity-threshold.

To my understanding, some lints can be tuned and they are listed here: Lint Configuration Options.

Unless I missunderstood, the only way to set those configurations is in a in a TOML file named clippy.toml or .clippy.toml.

I like to set all my lint configuration in my lib.rs/main.rs in the attributes #![allow/warn/deny/forbid(...)] at the beginnig of the file.

It lets me see a nice overview of all my lints settings.

Is it possible for the configurable lints to have their config inlined in the attribute so we won't need an extra clippy.toml file ?

I imagined something like:

#![warn(clippy::<lints>(<config1>=<value1>, <config2>=<value2>, ...))]

Example with clippy::cognitive_complexity:

// # lib.rs

//! My demo library.

// rustc lints
#![forbid(unsafe_code)]
#![deny(non_ascii_idents, unreachable_pub)]
#![warn(rust_2018_idioms)

// clippy lints
#![warn(
    clippy::pedantic, 
    clippy::cognitive_complexity(cognitive_complexity_threshold=30),
    clippy::branches_sharing_code,
)]

(Also, if it is doable, the config can be renamed shorter, cognitive_complexity_threshold -> threshold, as it cannot be misinterpreted for another lint.)

Version

No response

Additional Labels

C-enhancement

[J-ZhengLi]

good idea, I saw @flip1995 made a comment addressing similar stuff here, but I like yours better (XD), which means rustc lints could also benefit from this.

[flip1995]

The lint level attributes are not implemented by Clippy, but by rustc. So this change would have to be done in rustc. However, there is no such thing as a lint configuration, as far as the compiler/Clippy is concerned. You can only configure the tool. So each configuration is a 1-to-many relationship to lints, where N might be 1 (cog-comp). So conceptually you can't configure a single lint with a configuration. You can only configure the tool, in this case Clippy, to apply the configuration to all lints. Special casing some lints here would be a lot of work (upstream in rustc and in Clippy) for something I/we don't really want to support.

Also in the future you want to configure your global lints in the Cargo.toml file. Your Clippy [lint] configuration then goes into clippy.toml. Only a few configurations can be applied with an attribute.

So I mark this as not-planned.