Re: [PATCH] scripts: checkpatch: warn on Rust panicking methods

[Charalampos Mitrodimas <charmitro@posteo.net>]

Jason Hall <jason.kei.hall@gmail.com> writes:

> Added regex check in checkpatch.pl for common Rust panicking methods
> like unwrap() and expect().
>
> Allowed an exception if the line contains a '// PANIC:' comment.
>
> Suggested-by: Miguel Ojeda <ojeda@kernel.org>
> Link: https://github.com/Rust-for-linux/linux/issues/1191
> Signed-off-by: Jason Hall <jason.kei.hall@gmail.com>
> ---
>  scripts/checkpatch.pl | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index c0250244cf7a..fa9f55031129 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -3834,6 +3834,17 @@ sub process {
>  # check we are in a valid source file if not then ignore this hunk
>  		next if ($realfile !~ /\.(h|c|rs|s|S|sh|dtsi|dts)$/);
>  
> +# check for Rust unwrap/expect
> +		if ($realfile =~ /\.rs$/ && $line =~ /^\+/) {
> +			if ($line =~ /\b(unwrap|expect)\s*\(/ &&

Using `\.` instead of `\b` would reduce false positives on string
literas. E.g. `println!("use unwrap() here")` would not trigger a
warning.

> +				$rawline !~ /\/\/\s*PANIC/ &&

Should this be:
       $rawline != /\/\/\s*PANIC:/ &&

i.e. with the colon?


Cheers,
C. Mitrodimas

> +				$line !~ /^\+\s*\/\// &&
> +				$line !~ /^\+\s*assert/) {
> +				WARN("RUST_UNWRAP",
> +					"Avoid unwrap() or expect() in Rust code; use proper error handling (Result) or justify with a '// PANIC: ...' comment.\n" . $herecurr);
> +			}
> +		}
> +
>  # check for using SPDX-License-Identifier on the wrong line number
>  		if ($realline != $checklicenseline &&
>  		    $rawline =~ /\bSPDX-License-Identifier:/ &&