[PATCH 2/3] Suspicious indentation detection after conditional statement

[Julius Werner]

From: Ivo Sieben <meltedpiano...@gmail.com>

Raise a SUSPICIOUS_CODE_INDENT warning when unexpected indentation is found
after a conditional statement. This can be used to find missing braces or
wrong indentation in/after a conditional statement.

For example the following error is caught;

        if (foo)
                bar();
                return;

Which can be either intended by the programmer as:

        if (foo)
                bar();
        return;

or
        if (foo) {
                bar();
                return;
        }

Signed-off-by: Ivo Sieben <meltedpiano...@gmail.com>
---
 scripts/checkpatch.pl | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index ffccbd2033e579..c1dfc0107be41d 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4185,6 +4185,47 @@ sub process {
                                WARN("SUSPECT_CODE_INDENT",
                                     "suspect code indent for conditional 
statements ($indent, $sindent)\n" . $herecurr . "$stat_real\n");
                        }
+
+# Also check if the next statement after the previous condition has the same 
indent
+                       my ($stat_next, undef, $line_nr_next_next) =
+                               ctx_statement_block($line_nr_next, 
$remain_next, $off_next);
+                       my $s_next = $stat_next;
+
+                       # Remove line prefixes
+                       $s_next =~ s/\n./\n/gs;
+
+                       # Remove any comments
+                       $s_next =~ s/$;//g;
+
+                       # Skip this check for in case next statement starts 
with 'else'
+                       if ($s_next !~ /\s*\belse\b/) {
+
+                               # Remove while that belongs to a do {} while
+                               if ($stat =~ /\bdo\b/) {
+                                       $s_next =~ 
s/^.*\bwhile\b\s*($balanced_parens)\s*?//;
+                               }
+
+                               # Remove blank lines
+                               $s_next =~ s/\s*\\?\n//g;
+
+                               # Get the real next lines
+                               my $next_nof_lines = $line_nr_next_next - 
$line_nr_next;
+                               my $stat_next_real = raw_line($line_nr_next, 
$next_nof_lines);
+                               if (!defined($stat_next_real)) {
+                                       $stat_next_real = "";
+                               } elsif ($next_nof_lines > 1) {
+                                       $stat_next_real = 
"[...]\n$stat_next_real";
+                               }
+                               my (undef, $nindent) = line_stats('+' . 
$s_next);
+
+                               #print "stat_next<$stat_next> stat<$stat> 
indent<$indent> nindent<$nindent> s_next<$s_next> 
stat_next_real<$stat_next_real>\n";
+
+                               if ($nindent > $indent) {
+                                       WARN("SUSPICIOUS_CODE_INDENT",
+                                            "suspicious code indentation after 
conditional statements\n" .
+                                            $herecurr . 
"$stat_real\n$stat_next_real\n");
+                               }
+                       }
                }
 
                # Track the 'values' across context and added lines.
-- 
2.29.2