A script that checks if a mesa patch indentation uses 3 spaces and no tabs. Run it with: ./check-mesa-diff.pl <patch-filename>

check-mesa-diff.pl

#!/usr/bin/perl

use strict;
use warnings;

use Term::ANSIColor;
local $Term::ANSIColor::AUTOLOCAL = 1;

my $fname = $ARGV[0];
if(not defined $fname) {
	die "You must set the patch filename.\n";
}

my $full_line;
my $lnum = 0;
my $llen = 0;
my $counter = 0;

open(my $fh, '<', $fname) or die "Couldn't open file $fname.\n";
while(!eof($fh)) {
	defined(my $line = readline $fh) or die "Failed to read line.\n";
	$lnum++;

# inserted lines (diff)
	$full_line = $line;
	my $line_printed = 0;

	if($line =~ m/^\+/) {
# remove the insert (+) character at the beginning		
		substr($line, 0, 1) = "";
		$llen = length($line);

# if the first characters are tabs die with message
		if($line =~ m/(^(\t+))/) {
			close($fh);
			goto TAB_DEATH;
		}

# if the line begins with a space count spaces
		if($line =~ /^( +).*$/) {
			my $spaces = $1;
			my $num_spaces = length($spaces);

			if(($num_spaces % 3) != 0) {
				my $next_char = substr($line, $num_spaces, 1);
				if(!($next_char eq '*')) {
					my $string = qq[$lnum:\t$full_line];
					print colored($string, 'yellow on_black');
					print color('reset');
					$line_printed++;
				}
				$counter++;
			}

			if($num_spaces == ($llen - 1)) {
				close($fh);
				die "Diff line $lnum contains only spaces:\n$full_line";
			}
			my $next_char = substr($line, $num_spaces, 1);

			if($next_char eq "\t") {
				close($fh);
				goto TAB_DEATH;
			}
		}
	}
	if(!$line_printed) {
		print color('reset');
		print "$lnum:\t$full_line";
	}
}
close($fh);

if($counter) {
	print "\nSome lines start with a number of spaces that is not a ";
	print "multiple of 3.\nPlease check your indentation.\n\n";
}

exit(0);

TAB_DEATH:
die "In line: $lnum you use tab instead of space:\n$full_line\n";