Index: libcaca/trunk/ruby/t/tc_display.rb
===================================================================
--- libcaca/trunk/ruby/t/tc_display.rb	(revision 2297)
+++ libcaca/trunk/ruby/t/tc_display.rb	(revision 2298)
@@ -4,16 +4,23 @@
 class TC_Canvas < Test::Unit::TestCase
     def test_create
-	d = Caca::Display.new
+        d = Caca::Display.new
         assert_not_nil(d, 'Display creation failed')
     end
     def test_create_with_driver
-	d = Caca::Display.new(nil, Caca::Display.driver_list[0])
+        d = Caca::Display.new(Caca::Display.driver_list[0])
         assert_not_nil(d, 'Display creation failed')
+    end
+    def test_create_wrong_args
+        assert_raise(RuntimeError){Caca::Display.new("plop")}
+        driver = Caca::Display.driver_list[0]
+        assert_raise(ArgumentError){Caca::Display.new(driver, driver)}
+        c = Cucul::Canvas.new(3, 3)
+        assert_raise(ArgumentError){Caca::Display.new(c, c)}
     end
     def test_create_from_canvas
         c = Cucul::Canvas.new(3, 3)
-	d = Caca::Display.new(c)
+        d = Caca::Display.new(c)
         assert_not_nil(d, 'Display creation failed')
-	assert_equal(d.canvas, c, 'Wrong canvas')
+        assert_equal(d.canvas, c, 'Wrong canvas')
     end
     def test_set_title