checkpatch: add --strict check for ifs with unnecessary parentheses

An if statement test like
	if ((foo == bar) && (baz != qux))
can arguably be better written without the parentheses as
	if (foo == bar && baz != qux)

Add a test to find these cases.

Link: http://lkml.kernel.org/r/dcd0561ddd0fa43c51a420d53b550d738bf42001.1502734458.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.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 2017-09-08 16:16:01 -07:00 committed by Linus Torvalds
parent afdb05e9d6
commit 63b7c73ec8
1 changed files with 24 additions and 0 deletions

View File

@ -4496,6 +4496,30 @@ sub process {
}
}
# check for unnecessary parentheses around comparisons in if uses
if ($^V && $^V ge 5.10.0 && defined($stat) &&
$stat =~ /(^.\s*if\s*($balanced_parens))/) {
my $if_stat = $1;
my $test = substr($2, 1, -1);
my $herectx;
while ($test =~ /(?:^|[^\w\&\!\~])+\s*\(\s*([\&\!\~]?\s*$Lval\s*(?:$Compare\s*$FuncArg)?)\s*\)/g) {
my $match = $1;
# avoid parentheses around potential macro args
next if ($match =~ /^\s*\w+\s*$/);
if (!defined($herectx)) {
$herectx = $here . "\n";
my $cnt = statement_rawlines($if_stat);
for (my $n = 0; $n < $cnt; $n++) {
my $rl = raw_line($linenr, $n);
$herectx .= $rl . "\n";
last if $rl =~ /^[ \+].*\{/;
}
}
CHK("UNNECESSARY_PARENTHESES",
"Unnecessary parentheses around '$match'\n" . $herectx);
}
}
#goto labels aren't indented, allow a single space however
if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
!($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {