Re: [PATCH] rust: cpufreq: fix clippy::double_parens warning in Policy doctest

From: Gary Guo

Date: Wed Mar 04 2026 - 15:40:15 EST


On Wed Mar 4, 2026 at 8:28 PM GMT, Gary Guo wrote:
> On Wed Mar 4, 2026 at 8:07 PM GMT, John Hubbard wrote:
>> On 3/4/26 12:06 PM, Gary Guo wrote:
>>> On Wed Mar 4, 2026 at 7:53 PM GMT, John Hubbard wrote:
>>>> Clippy reports:
>>>> warning: consider removing unnecessary double parentheses
>>>> --> rust/kernel/cpufreq.rs:410:60
>>>> |
>>>> 410 | pr_info!("The policy details are: {:?}\n", (policy.cpu(), policy.cur()));
>>>> | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>
>>> This looks like a false positive, probably due to how our fmt macro works?
>>
>> Probably, but in any case we need to remain clippy clean, so this
>> work-around seems about right, yes?
>>
>>
>> thanks,
>
> Can you try this?
>
> Best,
> Gary
>
> -- >8 --
>
> diff --git a/rust/macros/fmt.rs b/rust/macros/fmt.rs
> index ce6c7249305a..51988a69af21 100644
> --- a/rust/macros/fmt.rs
> +++ b/rust/macros/fmt.rs
> @@ -2,7 +2,7 @@
>
> use std::collections::BTreeSet;
>
> -use proc_macro2::{Ident, TokenStream, TokenTree};
> +use proc_macro2::{Group, Ident, TokenStream, TokenTree};
> use quote::quote_spanned;
>
> /// Please see [`crate::fmt`] for documentation.
> @@ -69,7 +69,8 @@ pub(crate) fn fmt(input: TokenStream) -> TokenStream {
> }
> (None, acc)
> })();
> - args.extend(quote_spanned!(first_span => #lhs #adapter(&(#rhs))));
> + let rhs = Group::new(proc_macro2::Delimiter::None, rhs);
> + args.extend(quote_spanned!(first_span => #lhs #adapter(&#rhs)));

Actually `Delimiter::None` isn't fully fixed [1], so perhaps let's done use this
approach.

Injecting a `#[allow(clippy::double_parens)]` would probably a better approach
today.

Best,
Gary

Link: https://github.com/rust-lang/rust/issues/67062 [1]

> }
> };