[RenderText] added test for AppendText

ui/gfx/render_text_unittest.cc

Index: ui/gfx/render_text_unittest.cc
diff --git a/ui/gfx/render_text_unittest.cc b/ui/gfx/render_text_unittest.cc
index 42825579ec6cb0b68fe701de431a2c1444d5c1f7..aa937ab5b95fbd9f71d0d32aa731babd88daf49b 100644
--- a/ui/gfx/render_text_unittest.cc
+++ b/ui/gfx/render_text_unittest.cc
@@ -216,6 +216,31 @@ class TestRectangleBuffer {
 class RenderTextTest : public testing::Test {
 };
 
+TEST_F(RenderTextTest, AppendText) {

[msw, 2015/03/24 01:47:16]

Move this test below ApplyStyles.

[dschuyler, 2015/03/24 19:37:08]

Done.

+  // Ensure AppendText maintains current text styles.
+  scoped_ptr<RenderText> render_text(RenderText::CreateInstance());
+  const SkColor color = SK_ColorRED;
+  render_text->SetColor(color);

[msw, 2015/03/24 01:47:16]

This test should also ensure ranged values from Apply[Color|Style|BaselineStyle]
aren't lost on AppendText. As is, this test doesn't ensure anything beyond the
SetStyles test, and would pass even if ranged styles were cleared on AppendText.

+  render_text->SetBaselineStyle(SUPERSCRIPT);
+  render_text->SetStyle(BOLD, true);
+  render_text->SetStyle(UNDERLINE, false);
+  const wchar_t* const cases[] = { L"Hello", L"", L" ", L"world" };
+  size_t total_length = 0;
+  for (size_t i = 0; i < arraysize(cases); ++i) {
+    EXPECT_TRUE(render_text->colors().EqualsValueForTesting(color));
+    EXPECT_TRUE(render_text->baselines().EqualsValueForTesting(SUPERSCRIPT));
+    EXPECT_TRUE(render_text->styles()[BOLD].EqualsValueForTesting(true));
+    EXPECT_TRUE(render_text->styles()[UNDERLINE].EqualsValueForTesting(false));
+    EXPECT_EQ(total_length, render_text->GetDisplayText().length());
+    base::string16 str = WideToUTF16(cases[i]);
+    render_text->AppendText(str);
+    total_length += str.length();
+    EXPECT_EQ(total_length, render_text->GetDisplayText().length());
+  }
+  const base::string16 result_string = ASCIIToUTF16("Hello world");
+  EXPECT_EQ(render_text->GetDisplayText(), result_string);
+}
+
 TEST_F(RenderTextTest, DefaultStyles) {
   // Check the default styles applied to new instances and adjusted text.
   scoped_ptr<RenderText> render_text(RenderText::CreateInstance());