[perl-Cairo] Make t/CairoPath.t more robust

[Torsten SchÃnfeld <tsch src gnome org>]

commit a1cd2e45b4ee49a724ae5d7e854ad9829eebf00d
Author: Torsten SchÃnfeld <kaffeetisch gmx de>
Date:   Sat Apr 7 20:01:31 2012 +0200

    Make t/CairoPath.t more robust
    
    The end of a path that took a round trip into cairo and back might differ
    for different versions of cairo.  Hence, compare only the beginning with
    the expected path.

 t/CairoPath.t |   42 ++++++++++++++++++++++--------------------
 1 files changed, 22 insertions(+), 20 deletions(-)
---
diff --git a/t/CairoPath.t b/t/CairoPath.t
index 770e464..27a3aad 100644
--- a/t/CairoPath.t
+++ b/t/CairoPath.t
@@ -11,17 +11,11 @@ use strict;
 use warnings;
 use Cairo;
 
-use Test::More;
+use Test::More tests => 18;
 
 use constant IMG_WIDTH => 256;
 use constant IMG_HEIGHT => 256;
 
-if (Cairo::VERSION >= Cairo::VERSION_ENCODE (1, 4, 0)) {
-  plan tests => 6;
-} else {
-  plan skip_all => 'path behavior not predictable on cairo < 1.4';
-}
-
 my $surf = Cairo::ImageSurface->create ('rgb24', IMG_WIDTH, IMG_HEIGHT);
 my $cr = Cairo::Context->create ($surf);
 
@@ -40,14 +34,7 @@ my $expected_path = [
 ];
 
 my $path = $cr->copy_path;
-is_deeply ($path, $expected_path);
-
-sub paths_agree {
-  my ($cr, $path, $expected_path) = @_;
-  $cr->new_path;
-  $cr->append_path ($path);
-  is_deeply ($cr->copy_path, $expected_path);
-}
+paths_agree ($path, $expected_path);
 
 # Modifying single point values.
 foreach ($path, $expected_path) {
@@ -57,21 +44,21 @@ foreach ($path, $expected_path) {
   $_->[2]{points}[2][0] = 99;
   $_->[2]{points}[2][1] = 1010;
 }
-paths_agree ($cr, $path, $expected_path);
+path_round_trip_ok ($cr, $path, $expected_path);
 
 # Modifying single points.
 foreach ($path, $expected_path) {
   $_->[1]{points}[0] = [333, 444];
   $_->[2]{points}[2] = [77, 88];
 }
-paths_agree ($cr, $path, $expected_path);
+path_round_trip_ok ($cr, $path, $expected_path);
 
 # Replacing all points.
 foreach ($path, $expected_path) {
   $_->[1]{points} = [[3333, 4444]];
   $_->[2]{points} = [[55, 66], [77, 88], [99, 1010]];
 }
-paths_agree ($cr, $path, $expected_path);
+path_round_trip_ok ($cr, $path, $expected_path);
 
 # Replacing and adding path segments.
 my @cloned_path = @{$path};
@@ -86,9 +73,24 @@ foreach (\ cloned_path, $expected_path) {
     type => 'line-to',
     points => [[23, 42]] };
 }
-paths_agree ($cr, \ cloned_path, $expected_path);
+path_round_trip_ok ($cr, \ cloned_path, $expected_path);
 
 # Passing bare arrays into Cairo.
 $cr->new_path;
 $cr->append_path ($expected_path);
-is_deeply ($cr->copy_path, $expected_path);
+paths_agree ($cr->copy_path, $expected_path);
+
+sub path_round_trip_ok {
+  my ($cr, $path, $expected_path) = @_;
+  $cr->new_path;
+  $cr->append_path ($path);
+  paths_agree ($cr->copy_path, $expected_path);
+}
+
+sub paths_agree {
+  my ($path, $expected_path) = @_;
+  # Only the first three entries seem to be reliable across cairo versions.
+  for (0..2) {
+    is_deeply ($path->[$_], $expected_path->[$_]);
+  }
+}