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>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 2287a0b..143ab5c 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4496,6 +4496,30 @@
}
}
+# 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:/)) {
