From 63b7c73ec86b8c73560d22c7552bc6f47f0b8da9 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Fri, 8 Sep 2017 16:16:01 -0700 Subject: [PATCH] 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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 2287a0bca863..143ab5ca2c41 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -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:/)) { -- 2.20.1