From 189248d8f4f3ac2fba30da9b40133b5891df95fc Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Thu, 23 Jan 2014 15:54:47 -0800 Subject: [PATCH] checkpatch: check for if's with unnecessary parentheses If statements don't need multiple parentheses around tested comparisons like "if ((foo == bar))". An == comparison maybe a sign of an intended assignment, so emit a slightly different message if so. Signed-off-by: Joe Perches Reviewed-by: Josh Triplett Cc: Manfred Spraul Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 3e0b3f4d3420..57f10db4accd 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3254,6 +3254,20 @@ sub process { } } +# if statements using unnecessary parentheses - ie: if ((foo == bar)) + if ($^V && $^V ge 5.10.0 && + $line =~ /\bif\s*((?:\(\s*){2,})/) { + my $openparens = $1; + my $count = $openparens =~ tr@\(@\(@; + my $msg = ""; + if ($line =~ /\bif\s*(?:\(\s*){$count,$count}$LvalOrFunc\s*($Compare)\s*$LvalOrFunc(?:\s*\)){$count,$count}/) { + my $comp = $4; #Not $1 because of $LvalOrFunc + $msg = " - maybe == should be = ?" if ($comp eq "=="); + WARN("UNNECESSARY_PARENTHESES", + "Unnecessary parentheses$msg\n" . $herecurr); + } + } + # Return of what appears to be an errno should normally be -'ve if ($line =~ /^.\s*return\s*(E[A-Z]*)\s*;/) { my $name = $1;