Invalidate the previous caret even if the parent text node is removed.

third_party/WebKit/Source/core/editing/FrameSelectionTest.cpp

Index: third_party/WebKit/Source/core/editing/FrameSelectionTest.cpp
diff --git a/third_party/WebKit/Source/core/editing/FrameSelectionTest.cpp b/third_party/WebKit/Source/core/editing/FrameSelectionTest.cpp
index 639f888434cb57c6257d7c74c33b1d97adaaab07..9d46a31abd1d5aca647228f9699df8db815be791 100644
--- a/third_party/WebKit/Source/core/editing/FrameSelectionTest.cpp
+++ b/third_party/WebKit/Source/core/editing/FrameSelectionTest.cpp
@@ -14,6 +14,7 @@
 #include "core/html/HTMLDocument.h"
 #include "core/layout/LayoutView.h"
 #include "core/paint/PaintInfo.h"
+#include "core/paint/PaintLayer.h"
 #include "core/testing/DummyPageHolder.h"
 #include "platform/graphics/paint/DrawingRecorder.h"
 #include "platform/graphics/paint/PaintController.h"
@@ -35,6 +36,9 @@ protected:
     PassRefPtrWillBeRawPtr<Text> appendTextNode(const String& data);
     int layoutCount() const { return dummyPageHolder().frameView().layoutCount(); }
 
+    bool ShouldPaintCaretForTesting() const { return selection().ShouldPaintCaretForTesting(); }
+    bool isPreviousCaretDirtyForTesting() const { return selection().isPreviousCaretDirtyForTesting(); }
+
 private:
     RefPtrWillBePersistent<Text> m_textNode;
 };
@@ -117,7 +121,7 @@ TEST_F(FrameSelectionTest, PaintCaretShouldNotLayout)
     selection().setCaretVisible(true);
     setSelection(validSelection);
     EXPECT_TRUE(selection().isCaret());
-    EXPECT_TRUE(selection().ShouldPaintCaretForTesting());
+    EXPECT_TRUE(ShouldPaintCaretForTesting());
 
     int startCount = layoutCount();
     {
@@ -135,6 +139,54 @@ TEST_F(FrameSelectionTest, PaintCaretShouldNotLayout)
     EXPECT_EQ(startCount, layoutCount());
 }
 
+TEST_F(FrameSelectionTest, InvalidatePreviousCaretAfterRemovingLastCharacter)
+{
+    RefPtrWillBeRawPtr<Text> text = appendTextNode("Hello, World!");
+    document().view()->updateAllLifecyclePhases();
+
+    document().body()->setContentEditable("true", ASSERT_NO_EXCEPTION);
+    document().body()->focus();
+    EXPECT_TRUE(document().body()->focused());
+
+    selection().setCaretVisible(true);
+    EXPECT_TRUE(selection().isCaret());
+    EXPECT_TRUE(ShouldPaintCaretForTesting());
+
+    // Simulate to type "Hello, World!".
+    DisableCompositingQueryAsserts disabler;
+    selection().moveTo(createVisiblePosition(selection().end(), selection().affinity()), NotUserTriggered);
+    selection().setCaretRectNeedsUpdate();
+    EXPECT_TRUE(selection().isCaretBoundsDirty());
+    EXPECT_FALSE(isPreviousCaretDirtyForTesting());
+    selection().invalidateCaretRect();
+    EXPECT_FALSE(selection().isCaretBoundsDirty());
+    EXPECT_TRUE(isPreviousCaretDirtyForTesting());
+
+    // Simulate to remove all except for "H".
+    text->replaceWholeText("H");
+    selection().moveTo(createVisiblePosition(selection().end(), selection().affinity()), NotUserTriggered);
+    selection().setCaretRectNeedsUpdate();
+    EXPECT_TRUE(selection().isCaretBoundsDirty());
+    // "H" remains so early previousCaret invalidation isn't needed.
+    EXPECT_TRUE(isPreviousCaretDirtyForTesting());
+    selection().invalidateCaretRect();
+    EXPECT_FALSE(selection().isCaretBoundsDirty());
+    EXPECT_TRUE(isPreviousCaretDirtyForTesting());
+
+    // Simulate to remove the last character.
+    document().body()->removeChild(text);
+    // This line is the objective of this test.
+    // As removing the last character, early previousCaret invalidation is executed.
+    EXPECT_FALSE(isPreviousCaretDirtyForTesting());
+    document().updateLayoutIgnorePendingStylesheets();
+    selection().setCaretRectNeedsUpdate();
+    EXPECT_TRUE(selection().isCaretBoundsDirty());
+    EXPECT_FALSE(isPreviousCaretDirtyForTesting());
+    selection().invalidateCaretRect();
+    EXPECT_FALSE(selection().isCaretBoundsDirty());
+    EXPECT_TRUE(isPreviousCaretDirtyForTesting());
+}
+
 #define EXPECT_EQ_SELECTED_TEXT(text) \
     EXPECT_EQ(text, WebString(selection().selectedText()).utf8())