t0021/rot13-filter: fix list comparison

Since edcc858 ("convert: add filter.<driver>.process
option", 2016-10-16) when t0021/rot13-filter.pl was created, list
comparison in this perl script have been quite broken.

packet_txt_read() returns a 2-element list, and the right hand
side of "eq" also has a list with (two, elements), but "eq" takes
the last element of the list on each side, and compares them. The
first elements (0 or 1) on the right hand side lists do not matter,
which means we do not require to see a flush at the end of the
version -- a simple empty string or an EOF would do, which is
definitely not what we want.

Signed-off-by: Christian Couder <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: chriscool

t/t0021/rot13-filter.pl

@@ -55,6 +55,20 @@ sub rot13 {
 	return $str;
 }
 
+sub packet_compare_lists {
+	my ($expect, @result) = @_;
+	my $ix;
+	if (scalar @$expect != scalar @result) {
+		return undef;
+	}
+	for ($ix = 0; $ix < $#result; $ix++) {
+		if ($expect->[$ix] ne $result[$ix]) {
+			return undef;
+		}
+	}
+	return 1;
+}
+
 sub packet_bin_read {
 	my $buffer;
 	my $bytes_read = read STDIN, $buffer, 4;
@@ -110,18 +124,25 @@ sub packet_flush {
 print $debug "START\n";
 $debug->flush();
 
-( packet_txt_read() eq ( 0, "git-filter-client" ) ) || die "bad initialize";
-( packet_txt_read() eq ( 0, "version=2" ) )         || die "bad version";
-( packet_bin_read() eq ( 1, "" ) )                  || die "bad version end";
+packet_compare_lists([0, "git-filter-client"], packet_txt_read()) ||
+	die "bad initialize";
+packet_compare_lists([0, "version=2"], packet_txt_read()) ||
+	die "bad version";
+packet_compare_lists([1, ""], packet_bin_read()) ||
+	die "bad version end";
 
 packet_txt_write("git-filter-server");
 packet_txt_write("version=2");
 packet_flush();
 
-( packet_txt_read() eq ( 0, "capability=clean" ) )  || die "bad capability";
-( packet_txt_read() eq ( 0, "capability=smudge" ) ) || die "bad capability";
-( packet_txt_read() eq ( 0, "capability=delay" ) )  || die "bad capability";
-( packet_bin_read() eq ( 1, "" ) )                  || die "bad capability end";
+packet_compare_lists([0, "capability=clean"], packet_txt_read()) ||
+	die "bad capability";
+packet_compare_lists([0, "capability=smudge"], packet_txt_read()) ||
+	die "bad capability";
+packet_compare_lists([0, "capability=delay"], packet_txt_read()) ||
+	die "bad capability";
+packet_compare_lists([1, ""], packet_bin_read()) ||
+	die "bad capability end";
 
 foreach (@capabilities) {
 	packet_txt_write( "capability=" . $_ );