Workaround for setComposition styling clobber

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

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/editing/InputMethodController.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/dom/Range.h"
 #include "core/editing/Editor.h"
@@ skipping 97 matching lines @@
     underlines.append(CompositionUnderline(0, 5, Color(255, 0, 0), false, 0));
     controller().setCompositionFromExistingText(underlines, 0, 5);
 
     Range* range = controller().compositionRange();
     EXPECT_EQ(0, range->startOffset());
     EXPECT_EQ(5, range->endOffset());
 
     PlainTextRange plainTextRange(PlainTextRange::create(*div, *range));
     EXPECT_EQ(0u, plainTextRange.start());
     EXPECT_EQ(5u, plainTextRange.end());
+
+    controller().setComposition(String("hellobar"), underlines, 8, 8);
+    range = controller().compositionRange();
+    EXPECT_EQ(0, range->startOffset());
+    EXPECT_EQ(8, range->endOffset());
+}
+
+TEST_F(InputMethodControllerTest, SetCompositionKeepingStyle)
+{
+    Element* div = insertHTMLElement(
+        "<div id='sample' contenteditable='true'><b>he</b>llo</div>", "sample");
+
+    Vector<CompositionUnderline> underlines;
+    underlines.append(CompositionUnderline(0, 5, Color(255, 0, 0), false, 0));
+    controller().setCompositionFromExistingText(underlines, 0, 5);
+
+    controller().setComposition(String("hell"), underlines, 4, 4);
+    EXPECT_STREQ("<b>he</b>ll", div->innerHTML().utf8().data());
+
+    controller().setComposition(String("hello"), underlines, 5, 5);
+    EXPECT_STREQ("<b>he</b>llo", div->innerHTML().utf8().data());
+}
+
+TEST_F(InputMethodControllerTest, SetCompositionWithMultiCodeTextKeepingStyle)
+{
+    Element* div = insertHTMLElement(
+        "<div id='sample' contenteditable='true'><i>hello</i>world<b>&#x1f3e0</b></div>", "sample"); // U+1F3E0 = 0xF0 0x9F 0x8F 0xA0 (UTF8)

[Changwan Ryu, 2016/09/27 09:17:11]

could you add some explanation to the UTF8 code you used?

[yabinh, 2016/09/27 12:46:47]

Done.

+
+    Vector<CompositionUnderline> underlines;
+    underlines.append(CompositionUnderline(0, 12, Color(255, 0, 0), false, 0));
+    controller().setCompositionFromExistingText(underlines, 0, 12);
+
+    controller().setComposition(String::fromUTF8("helloworld\xF0\x9F\x8F\xAB"), underlines, 12, 12);
+    EXPECT_STREQ("<i>hello</i>world<b>\xF0\x9F\x8F\xAB</b>", div->innerHTML().utf8().data());
+
+    controller().setComposition(String::fromUTF8("helloworld\xF0\x9F\x8F\xA0"), underlines, 12, 12);
+    EXPECT_STREQ("<i>hello</i>world<b>\xF0\x9F\x8F\xA0</b>", div->innerHTML().utf8().data());
 }
 
 TEST_F(InputMethodControllerTest, SelectionOnConfirmExistingText)
 {
     insertHTMLElement(
         "<div id='sample' contenteditable='true'>hello world</div>", "sample");
 
     Vector<CompositionUnderline> underlines;
     underlines.append(CompositionUnderline(0, 5, Color(255, 0, 0), false, 0));
     controller().setCompositionFromExistingText(underlines, 0, 5);
@@ skipping 350 matching lines @@
     Vector<CompositionUnderline> underlines;
     underlines.append(CompositionUnderline(0, 5, Color(255, 0, 0), false, 0));
     editable->focus();
 
     document().setTitle(emptyString());
     controller().setComposition("n", underlines, 0, 1);
     EXPECT_STREQ("beforeinput.data:n;input.data:n;", document().title().utf8().data());
 
     document().setTitle(emptyString());
     controller().setComposition("ni", underlines, 0, 1);
-    EXPECT_STREQ("beforeinput.data:ni;input.data:ni;", document().title().utf8().data());
+    EXPECT_STREQ("beforeinput.data:i;input.data:i;", document().title().utf8().data());
 
     document().setTitle(emptyString());
     controller().finishComposingText(InputMethodController::KeepSelection);
     EXPECT_STREQ("beforeinput.data:ni;input.data:ni;", document().title().utf8().data());
 }
 
 } // namespace blink