Update references to use new class method

1 files changed, 3 insertions, 2 deletions

diff --git a/test/stylesheet/tc_styles.rb b/test/stylesheet/tc_styles.rb
index c46b6bdb..1c04abd7 100644
--- a/test/stylesheet/tc_styles.rb
+++ b/test/stylesheet/tc_styles.rb
@@ -136,12 +136,13 @@ class TestStyles < Test::Unit::TestCase
     original = @styles.fonts.first
     @styles.add_style :b => 1, :sz => 99
     created = @styles.fonts.last
-    original_attributes = original.instance_values
+    original_attributes = Axlsx.instance_values(original)
     assert_equal(1, created.b)
     assert_equal(99, created.sz)
     copied = original_attributes.reject{ |key, value| %w(b sz).include? key }
+    instance_vals = Axlsx.instance_values(created)
     copied.each do |key, value|
-      assert_equal(created.instance_values[key], value)
+      assert_equal(instance_vals[key], value)
     end
   end