How to add customized lint pass for rustc?

[StevenJiang1110]

I recently learned from an old technique article that we can add customized lint pass with compiler plugin. This is quite a convenient way to do some lightweight code check during compilation. However, compiler plugin is already a deprecated feature, which may be removed from compiler in the near future. So I wonder what's the proper way to add customized lint pass now without compiler plugin?

Below are a simple example code I used now, which add a simple lint pass with compiler plugin. (I omit codes that are not important)

//! my-lint-plugin/src/lib.rs
//! define a new lint plugin

use rustc_lint::{LateContext, LateLintPass};
declare_lint!(
    MY_CHECKER,
    Warn,
    "A check for demonstration"
);
declare_lint_pass!(Pass => [MY_CHECKER]);

impl<'tcx> LateLintPass<'tcx> for Pass {
    fn check_fn(
        &mut self,
        late_ctx: &LateContext<'tcx>,
        ......
    ) {
        // check each function
    }
}

#[no_mangle]
fn __rustc_plugin_registrar(reg: &mut Registry) {
    reg.lint_store.register_lints(&[&MY_CHECKER]);
    reg.lint_store.register_late_pass(|_| box Pass);
}

//! my-lint-plugin-test/src/main.rs
//! test the plugin. The plugin will work on this crate.
//! When building this crate, our lint pass will be called.
#![feature(plugin, register_tool)]
#![plugin(my_lint_plugin)] // This feature was deprecated!
#![register_tool(my_lint)]

fn main() {
    // ......
}

[Cerber-Ursi]

@StevenJiang1110

what's the proper way to add customized lint pass now without compiler plugin?

For now probably the only way is using the external tool which uses rustc as library, as it is done with clippy.

[StevenJiang1110]

Thanks a lot. I will look at how clippy works.