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 <joe@perches.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Joe Perches 2014-01-23 15:54:47 -08:00 committed by Linus Torvalds
parent c76f4cb3d2
commit 189248d8f4

View File

@ -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" . $herecurr);
}
}
# Return of what appears to be an errno should normally be -'ve # Return of what appears to be an errno should normally be -'ve
if ($line =~ /^.\s*return\s*(E[A-Z]*)\s*;/) { if ($line =~ /^.\s*return\s*(E[A-Z]*)\s*;/) {
my $name = $1; my $name = $1;