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Message-ID: <9ede7de2b1da90e025e64c86ffbcc7f44843de69.camel@perches.com>
Subject: Re: [PATCH v5] 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 03:31:55 -0800
In-Reply-To: <20201122111025.17978-1-yashsri421@gmail.com>
References: <1823e72eb92280d30457dda49e0a0036dee15dd3.camel@perches.com>
         <20201122111025.17978-1-yashsri421@gmail.com>
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On Sun, 2020-11-22 at 16:40 +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 adding logical operator at the end of previous
> line and removing from current line, if both the lines are additions
> (ie start with '+')
> 
> Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
> ---
> changes in v2: quote $operator at substitution
> 
> changes in v3: add a check for previous line ending with comment;
> If so, insert $operator at the last non-comment, non-whitespace char of the previous line
> 
> changes in v4: improve the matching mechanism by matching line termination at comment or white space;
> insert the operator before comments (if any) separated by a whitespace;
> append the comment and its pre-whitespace after the inserted operator (if comment was present),
> ie if no comment was present nothing will be inserted after the operator
> 
> changes in v5: improve regex for comment and line end with '$;'
> 
> ?scripts/checkpatch.pl | 13 +++++++++++--
> ?1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 5b1a5a65e69a..708a56f31466 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -3553,8 +3553,17 @@ 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 && $prevrawline =~ /^\+/) {
> +				# add logical operator to the previous line, remove from current line
> +				if ($prevline =~ /[\s$;]*$/) {
> +					my $line_end = substr($prevrawline, $-[0]);
> +					$fixed[$fixlinenr - 1] =~ s/\Q$line_end\E/ $operator$line_end/;
> +				}
> +				$fixed[$fixlinenr] =~ s/\Q$operator\E\s*//;
> +			}
> ?		}
> ?
> 
> ?# check indentation starts on a tab stop