Implement eliding/truncating at end in RenderText

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 c8c50d428141cf2be2af4ae08c33b522a9befff6..aa28b2459fe61e5631cb0dac61e3630ef0110ea2 100644
--- a/ui/gfx/render_text_unittest.cc
+++ b/ui/gfx/render_text_unittest.cc
@@ -401,6 +401,92 @@ TEST_F(RenderTextTest, RevealObscuredText) {
   EXPECT_EQ(valid_expect_5_and_6, render_text->GetLayoutText());
 }
 
+TEST_F(RenderTextTest, ElidedText) {
+  // TODO(skanuj) : Add more test cases for following
+  // - RenderText styles.
+  // - Cross interaction of truncate, elide and obscure.
+  // - ElideText tests from text_elider.cc.
+  struct {
+    const wchar_t* text;
+    const wchar_t* layout_text;
+  } cases[] = {
+    // Strings shorter than the elision width should be laid out in full.
+    { L""        , L""        },
+    { kWeak      , kWeak      },
+    { kLtr       , kLtr       },
+    { kLtrRtl    , kLtrRtl    },
+    { kLtrRtlLtr , kLtrRtlLtr },
+    { kRtl       , kRtl       },
+    { kRtlLtr    , kRtlLtr    },
+    { kRtlLtrRtl , kRtlLtrRtl },
+    // Strings as long as the elision width should be laid out in full.
+    { L"012ab",   L"012ab"   },
+    // Long strings should be elided with an ellipsis appended at the end.
+    { L"012" L"abc"                  , L"012a\x2026"               },
+    { L"012" L"ab" L"\x5d0\x5d1"     , L"012a\x2026"               },
+    { L"012" L"a" L"\x5d1" L"b"      , L"012a\x2026"               },
+    // No RLM marker added as digits (012) have weak directionality.
+    { L"01" L"\x5d0\x5d1\x5d2" L"ab" , L"01\x5d0\x5d1\x2026"       },
+    // RLM marker added as "ab" have strong LTR directionality.
+    { L"ab" L"\x5d0\x5d1\x5d2" L"ab" , L"ab\x5d0\x5d1\x2026\x200f" },
+    // Complex script is not handled. In this example, the "\x0915\x093f" is a
+    // compound glyph, but only half of it is elided.
+    { L"0123\x0915\x093f" L"abcd"          , L"0123\x0915\x2026"          },
+    // Surrogate pairs should be elided reasonably enough.
+    { L"0\x05e9\x05bc\x05c1\x05b8"         , L"0\x05e9\x05bc\x05c1\x05b8" },
+    { L"0\x05e9\x05bc\x05c1\x05b8" L"ab"   , L"0\x05e9\x05bc\x2026"       },
+    { L"01\x05e9\x05bc\x05c1\x05b8" L"ab"  , L"01\x05e9\x2026"            },
+    { L"012\x05e9\x05bc\x05c1\x05b8" L"ab" , L"012\x2026"                 },
+    { L"012\xF0\x9D\x84\x9E"               , L"012\xF0\x2026"             },
+  };
+
+  scoped_ptr<RenderText> expected_render_text(RenderText::CreateInstance());
+  expected_render_text->SetFontList(FontList("serif, Sans serif, 12px"));
+  expected_render_text->SetDisplayRect(gfx::Rect(0, 0, 9999, 100));
+
+  scoped_ptr<RenderText> render_text(RenderText::CreateInstance());
+  render_text->SetFontList(FontList("serif, Sans serif, 12px"));
+  render_text->SetElideBehavior(gfx::ELIDE_AT_END);
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(cases); i++) {
+    expected_render_text->SetText(WideToUTF16(cases[i].layout_text));
+    int expected_width = expected_render_text->GetContentWidth();
+    render_text->SetText(WideToUTF16(cases[i].text));
+#if defined(OS_WIN)
+    // TODO(skanuj): It seems in some cases (on Windows XP), the original text
+    // is shorter than the elided text.  Those cases should be modified by
+    // adding extra chars in the end.  Currently this problem happens for the
+    // following test case:
+    // { L"012\xF0\x9D\x84\x9E"               , L"012\xF0\x2026"             },
+    int original_width = render_text->GetContentWidth();
+    if ((base::win::GetVersion() < base::win::VERSION_VISTA) &&
+        (expected_width >= original_width))
+      continue;
+#endif
+    render_text->SetDisplayRect(gfx::Rect(0, 0, expected_width, 100));
+    EXPECT_EQ(WideToUTF16(cases[i].text), render_text->text());
+    EXPECT_EQ(WideToUTF16(cases[i].layout_text), render_text->GetLayoutText())
+        << "->For case " << i << ": " << cases[i].text << "\n";
+    expected_render_text->SetText(base::string16());
+  }
+}
+
+TEST_F(RenderTextTest, ElidedObscuredText) {
+  scoped_ptr<RenderText> expected_render_text(RenderText::CreateInstance());
+  expected_render_text->SetFontList(FontList("serif, Sans serif, 12px"));
+  expected_render_text->SetDisplayRect(gfx::Rect(0, 0, 9999, 100));
+  expected_render_text->SetText(WideToUTF16(L"**\x2026"));
+
+  scoped_ptr<RenderText> render_text(RenderText::CreateInstance());
+  render_text->SetFontList(FontList("serif, Sans serif, 12px"));
+  render_text->SetElideBehavior(gfx::ELIDE_AT_END);
+  render_text->SetDisplayRect(
+      gfx::Rect(0, 0, expected_render_text->GetContentWidth(), 100));
+  render_text->SetObscured(true);
+  render_text->SetText(WideToUTF16(L"abcdef"));
+  EXPECT_EQ(WideToUTF16(L"abcdef"), render_text->text());
+  EXPECT_EQ(WideToUTF16(L"**\x2026"), render_text->GetLayoutText());
+}
+
 TEST_F(RenderTextTest, TruncatedText) {
   struct {
     const wchar_t* text;