[ruby/reline] Add tests for top-level dialog color APIs

https://github.com/ruby/reline/commit/347a468c59

test/reline/test_reline.rb

@@ -46,6 +46,23 @@ class Reline::Test < Reline::TestCase
     Reline.completion_append_character = completion_append_character
   end
 
+  def test_dialog_color_configuration
+    # defaults
+    assert_equal(46, Reline.dialog_default_bg_color)
+    assert_equal(37, Reline.dialog_default_fg_color)
+    assert_equal(45, Reline.dialog_pointer_bg_color)
+    assert_equal(37, Reline.dialog_pointer_fg_color)
+
+    Reline.dialog_default_bg_color = 40
+    assert_equal(40, Reline.dialog_default_bg_color)
+    Reline.dialog_default_fg_color = 47
+    assert_equal(47, Reline.dialog_default_fg_color)
+    Reline.dialog_pointer_bg_color = 37
+    assert_equal(37, Reline.dialog_pointer_bg_color)
+    Reline.dialog_pointer_fg_color = 30
+    assert_equal(30, Reline.dialog_pointer_fg_color)
+  end
+
   def test_basic_word_break_characters
     basic_word_break_characters = Reline.basic_word_break_characters