Fix style_range_.erase() which caused style range not deleted completely and dcheck error.

BUG=99923
TEST=start chrome with new profile and --no-first-run --use-pure-view. type in  http://sites.google.com/a/google.com/ several times until autocomplete kicks in. continue typing while with autocomplete, browser should not crash.
Review URL: http://codereview.chromium.org/8252001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@105547 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 106 insertions, 5 deletions

diff --git a/ui/gfx/render_text.cc b/ui/gfx/render_text.cc
index 6d360b7..f8e58e7 100644
--- a/ui/gfx/render_text.cc
+++ b/ui/gfx/render_text.cc
@@ -105,13 +105,14 @@ void RenderText::SetText(const string16& text) {
     StyleRanges::iterator i;
     for (i = style_ranges_.begin(); i != style_ranges_.end(); i++) {
       if (i->range.start() >= text_.length()) {
-        i = style_ranges_.erase(i);
-        if (i == style_ranges_.end())
-          break;
-      } else if (i->range.end() > text_.length()) {
-        i->range.set_end(text_.length());
+        // Style ranges are sorted and non-overlapping, so all the subsequent
+        // style ranges should be out of text_.length() as well.
+        style_ranges_.erase(i, style_ranges_.end());
+        break;
       }
     }
+    // Since style ranges are sorted and non-overlapping, if there is a style
+    // range ends beyond text_.length, it must be the last one.
     style_ranges_.back().range.set_end(text_.length());
   }
 #ifndef NDEBUG
diff --git a/ui/gfx/render_text_unittest.cc b/ui/gfx/render_text_unittest.cc
index b66ac2d..c564c60 100644
--- a/ui/gfx/render_text_unittest.cc
+++ b/ui/gfx/render_text_unittest.cc
@@ -140,6 +140,65 @@ TEST_F(RenderTextTest, ApplyStyleRange) {
   EXPECT_EQ(ui::Range(0, 5), render_text->style_ranges()[0].range);
   EXPECT_FALSE(render_text->style_ranges()[0].underline);
   EXPECT_FALSE(render_text->style_ranges()[0].strike);
+
+  // Apply new style range that contains the 2nd last old style range.
+  render_text->SetText(ASCIIToUTF16("abcdefghi"));
+  underline.range = ui::Range(0, 3);
+  render_text->ApplyStyleRange(underline);
+  color.range = ui::Range(3, 6);
+  render_text->ApplyStyleRange(color);
+  strike.range = ui::Range(6, 9);
+  render_text->ApplyStyleRange(strike);
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+
+  color.foreground = SK_ColorRED;
+  color.range = ui::Range(2, 8);
+  render_text->ApplyStyleRange(color);
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 2), render_text->style_ranges()[0].range);
+  EXPECT_TRUE(render_text->style_ranges()[0].underline);
+  EXPECT_EQ(ui::Range(2, 8), render_text->style_ranges()[1].range);
+  EXPECT_EQ(SK_ColorRED, render_text->style_ranges()[1].foreground);
+  EXPECT_EQ(ui::Range(8, 9), render_text->style_ranges()[2].range);
+  EXPECT_TRUE(render_text->style_ranges()[2].strike);
+
+  // Apply new style range that contains multiple old style ranges.
+  render_text->SetText(ASCIIToUTF16("abcdefghiopq"));
+  underline.range = ui::Range(0, 3);
+  render_text->ApplyStyleRange(underline);
+  color.range = ui::Range(3, 6);
+  render_text->ApplyStyleRange(color);
+  strike.range = ui::Range(6, 9);
+  render_text->ApplyStyleRange(strike);
+  strike_underline.range = ui::Range(9, 12);
+  render_text->ApplyStyleRange(strike_underline);
+  EXPECT_EQ(4U, render_text->style_ranges().size());
+
+  color.foreground = SK_ColorRED;
+  color.range = ui::Range(2, 10);
+  render_text->ApplyStyleRange(color);
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 2), render_text->style_ranges()[0].range);
+  EXPECT_TRUE(render_text->style_ranges()[0].underline);
+  EXPECT_EQ(ui::Range(2, 10), render_text->style_ranges()[1].range);
+  EXPECT_EQ(SK_ColorRED, render_text->style_ranges()[1].foreground);
+  EXPECT_EQ(ui::Range(10, 12), render_text->style_ranges()[2].range);
+  EXPECT_TRUE(render_text->style_ranges()[2].underline);
+  EXPECT_TRUE(render_text->style_ranges()[2].strike);
+}
+
+static void SetTextWith2ExtraStyles(RenderText* render_text) {
+  render_text->SetText(ASCIIToUTF16("abcdefghi"));
+
+  gfx::StyleRange strike;
+  strike.strike = true;
+  strike.range = ui::Range(0, 3);
+  render_text->ApplyStyleRange(strike);
+
+  gfx::StyleRange underline;
+  underline.underline = true;
+  underline.range = ui::Range(3, 6);
+  render_text->ApplyStyleRange(underline);
 }
 
 TEST_F(RenderTextTest, StyleRangesAdjust) {
@@ -176,6 +235,47 @@ TEST_F(RenderTextTest, StyleRangesAdjust) {
   EXPECT_EQ(1U, render_text->style_ranges().size());
   EXPECT_EQ(ui::Range(0, 6), render_text->style_ranges()[0].range);
   EXPECT_FALSE(render_text->style_ranges()[0].strike);
+
+  // Test that ranges are removed correctly if they are outside the range of
+  // shorter text.
+  SetTextWith2ExtraStyles(render_text.get());
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+
+  render_text->SetText(ASCIIToUTF16("abcdefg"));
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 3), render_text->style_ranges()[0].range);
+  EXPECT_EQ(ui::Range(3, 6), render_text->style_ranges()[1].range);
+  EXPECT_EQ(ui::Range(6, 7), render_text->style_ranges()[2].range);
+
+  SetTextWith2ExtraStyles(render_text.get());
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+
+  render_text->SetText(ASCIIToUTF16("abcdef"));
+  EXPECT_EQ(2U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 3), render_text->style_ranges()[0].range);
+  EXPECT_EQ(ui::Range(3, 6), render_text->style_ranges()[1].range);
+
+  SetTextWith2ExtraStyles(render_text.get());
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+
+  render_text->SetText(ASCIIToUTF16("abcde"));
+  EXPECT_EQ(2U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 3), render_text->style_ranges()[0].range);
+  EXPECT_EQ(ui::Range(3, 5), render_text->style_ranges()[1].range);
+
+  SetTextWith2ExtraStyles(render_text.get());
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+
+  render_text->SetText(ASCIIToUTF16("abc"));
+  EXPECT_EQ(1U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 3), render_text->style_ranges()[0].range);
+
+  SetTextWith2ExtraStyles(render_text.get());
+  EXPECT_EQ(3U, render_text->style_ranges().size());
+
+  render_text->SetText(ASCIIToUTF16("a"));
+  EXPECT_EQ(1U, render_text->style_ranges().size());
+  EXPECT_EQ(ui::Range(0, 1), render_text->style_ranges()[0].range);
 }
 
 void RunMoveCursorLeftRightTest(RenderText* render_text,