Re: [PATCH v4] checkpatch: add fix option for LOGICAL_CONTINUATIONS

From: Joe Perches
Date: Sat Nov 21 2020 - 21:37:54 EST


On Sun, 2020-11-22 at 02:34 +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@xxxxxxxxx>
> ---
> 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

nak. I gave you a hint to the match string to use.

$prevline =~ /[\s$;]*$/

this matches either /* foo */ or // foo comment styles
(or optional blanks before EOL)

Try something like:
---
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index fab38b493cef..3c78cf0c219f 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3434,8 +3434,15 @@ 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
+ $prevline =~ /([\s$;]*$)/;
+ substr($fixed[$fixlinenr - 1], $-[0]) = " $operator" . substr($prevrawline, $-[0],$+[0]);
+ $fixed[$fixlinenr] =~ s/\Q$operator\E\s*//;
+ }
}

# check indentation starts on a tab stop