Adds official spec tests from libsass

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "libsass"]
 	path = libsass
 	url = git://github.com/mgreter/libsass.git
+[submodule "t/specs"]
+	path = t/specs
+	url = https://github.com/mgreter/sass-spec.git

t/99-sass_specs.t

@@ -0,0 +1,65 @@
+# -*- perl -*-
+
+# Usefult for debugging the xs with prints:
+# cd text-sass-xs && ./Build && perl -Mlib=blib/arch -Mlib=blib/lib t/04_perl_functions.t
+
+use strict;
+use warnings;
+
+my (@dirs, @tests);
+
+BEGIN
+{
+
+	@dirs = ('t/specs/spec');
+
+	while (my $dir = shift(@dirs))
+	{
+		opendir(my $dh, $dir) or die "error opening specs dir $dir";
+		while (my $ent = readdir($dh))
+		{
+			next if $ent eq ".";
+			next if $ent eq "..";
+			next if $ent eq "todo";
+			my $path = join("/", $dir, $ent);
+			next if $path eq "t/specs/spec/libsass/placeholder-mediaquery/input.scss";
+			next if $path eq "t/specs/spec/libsass/placeholder-nested/input.scss";
+			next if $path eq "t/specs/spec/extend-tests/226_test_nested_selector_with_child_selector_hack_extender_and_extendee/input.scss";
+			push @dirs, $path if -d $path;
+			push @tests, [$dir, $ent] if $ent =~ m/^input/;
+		}
+		closedir($dh);
+	}
+
+	# warn join(", ", map { $_->[0] } @tests), "\n";
+
+}
+
+use Test::More tests => scalar(@tests) * 2;
+
+use CSS::Sass;
+use File::Slurp;
+use Data::Dumper;
+
+my $sass;
+my ($r, $err);
+my ($src, $expect);
+my $ignore_whitespace = 1;
+
+foreach my $test (@tests)
+{
+	my $input_file = join("/", @{$test});
+	my $expected_file = join("/", $test->[0], 'expected_output.css');
+
+	$sass = CSS::Sass->new(include_paths => ['t/inc'], output_style => SASS_STYLE_NESTED);
+	$r = eval { $sass->compile_file($input_file) };
+	$expect = read_file($expected_file);
+	$expect =~ s/[\r\n]+/\n/g if $ignore_whitespace;
+	$r =~ s/[\r\n]+/\n/g if $ignore_whitespace;
+	chomp($expect) if $ignore_whitespace;
+	chomp($r) if $ignore_whitespace;
+
+	is    ($r, $expect,                                    "sass-spec " . $input_file);
+	is    ($err, undef,                                    "sass-spec " . $input_file);
+
+}