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>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3e0b3f4..57f10db 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3254,6 +3254,20 @@
}
}
+# 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;