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Message-ID: <afaa79a6d86a4184878595ced3f2de1a92a4058c.camel@perches.com>
Subject: Re: [PATCH v6] checkpatch: add fix option for LOGICAL_CONTINUATIONS
From:   Joe Perches <joe@perches.com>
To:     Aditya Srivastava <yashsri421@gmail.com>
Cc:     lukas.bulwahn@gmail.com,
        linux-kernel-mentees@lists.linuxfoundation.org,
        linux-kernel@vger.kernel.org
Date:   Sun, 22 Nov 2020 21:47:13 -0800
In-Reply-To: <20201122125908.22212-1-yashsri421@gmail.com>
References: <368300090d93ad66f7fb19076d076d4321a04c42.camel@perches.com>
         <20201122125908.22212-1-yashsri421@gmail.com>
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On Sun, 2020-11-22 at 18:29 +0530, Aditya Srivastava wrote:
> Currently, checkpatch warns if logical continuations are placed at the
> start of a line and not at the end of previous line.
> 
> E.g., running checkpatch on commit 3485507fc272 ("staging:
> bcm2835-camera: Reduce length of enum names") reports:
> 
> CHECK:LOGICAL_CONTINUATIONS: Logical continuations should be on the
> previous line
> +	if (!ret
> +	    && camera_port ==
> 
> Provide a simple fix by inserting logical operator at the last
> non-comment, non-whitespace char of the previous line and removing from
> current line, if both the lines are additions(ie start with '+')
> 
> Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
[]
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -3553,8 +3553,16 @@ sub process {
> ?
> 
> ?# check for && or || at the start of a line
> ?		if ($rawline =~ /^\+\s*(&&|\|\|)/) {
> -			CHK("LOGICAL_CONTINUATIONS",
> -			    "Logical continuations should be on the previous line\n" . $hereprev);
> +			my $operator = $1;
> +			if (CHK("LOGICAL_CONTINUATIONS",
> +				"Logical continuations should be on the previous line\n" . $hereprev) &&
> +			    $fix && $prevrawline =~ /^\+/) {
> +				# insert logical operator at last non-comment, non-whitepsace char on previous line
> +				$prevline =~ /[\s$;]*$/;
> +				my $line_end = substr($prevrawline, $-[0]);
> +				$fixed[$fixlinenr - 1] =~ s/\Q$line_end\E/ $operator$line_end/;

This doesn't work when the same leading whitespace and trailing whitespace
characters exist.

You need to use something like:

				$fixed[$fixlinenr - 1] =~ s/\Q$line_end\E$/ $operator$line_end/;

(note the $ after \E to use EOL)