checkpatch: add --fix option for some TRAILING_STATEMENTS

Single line code like:

	if (foo) bar;

should generally be written:

	if (foo)
		bar;

Add a --fix test to do so.

This fix is not done when an ASSIGN_IN_IF in the same line exists.

Link: https://lkml.kernel.org/r/20220128185924.80137-2-joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.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 b7c181e..046a018 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5551,6 +5551,7 @@ sub process {
                    defined($stat) && defined($cond) &&
                    $line =~ /\b(?:if|while|for)\s*\(/ && $line !~ /^.\s*#/) {
                        my ($s, $c) = ($stat, $cond);
+                       my $fixed_assign_in_if = 0;
 
                        if ($c =~ /\bif\s*\(.*[^<>!=]=[^=].*/s) {
                                if (ERROR("ASSIGN_IN_IF",
@@ -5575,6 +5576,7 @@ sub process {
                                                $newline .= ')';
                                                $newline .= " {" if (defined($brace));
                                                fix_insert_line($fixlinenr + 1, $newline);
+                                               $fixed_assign_in_if = 1;
                                        }
                                }
                        }
@@ -5598,8 +5600,20 @@ sub process {
                                        $stat_real = "[...]\n$stat_real";
                                }
 
-                               ERROR("TRAILING_STATEMENTS",
-                                     "trailing statements should be on next line\n" . $herecurr . $stat_real);
+                               if (ERROR("TRAILING_STATEMENTS",
+                                         "trailing statements should be on next line\n" . $herecurr . $stat_real) &&
+                                   !$fixed_assign_in_if &&
+                                   $cond_lines == 0 &&
+                                   $fix && $perl_version_ok &&
+                                   $fixed[$fixlinenr] =~ /^\+(\s*)((?:if|while|for)\s*$balanced_parens)\s*(.*)$/) {
+                                       my $indent = $1;
+                                       my $test = $2;
+                                       my $rest = rtrim($4);
+                                       if ($rest =~ /;$/) {
+                                               $fixed[$fixlinenr] = "\+$indent$test";
+                                               fix_insert_line($fixlinenr + 1, "$indent\t$rest");
+                                       }
+                               }
                        }
                }