Prevent the IME candidate window from flickering on Chrome OS

ui/views/controls/textfield/textfield_model_unittest.cc

 // 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 "ui/views/controls/textfield/textfield_model.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <vector>
@@ skipping 875 matching lines @@
   composition.selection = gfx::Range(3, 3);
   model.SetCompositionText(composition);
   EXPECT_TRUE(model.HasCompositionText());
   EXPECT_FALSE(model.HasSelection());
 
   // Cancel the composition.
   model.CancelCompositionText();
   composition_text_confirmed_or_cleared_ = false;
 
   // Restart composition with targeting "67" in "678".
-  composition.selection = gfx::Range(0, 2);
+  composition.selection = gfx::Range(1, 3);

[Yusuke Sato, 2017/05/18 17:14:31]

Changed to (1, 3) to make sure L898 has the precedence.

   composition.underlines.clear();
   composition.underlines.push_back(ui::CompositionUnderline(0, 2, 0, true));
   composition.underlines.push_back(ui::CompositionUnderline(2, 3, 0, false));
   model.SetCompositionText(composition);
   EXPECT_TRUE(model.HasCompositionText());
   EXPECT_TRUE(model.HasSelection());
+#if !defined(OS_CHROMEOS)
+  // |composition.selection| is ignored because SetCompositionText checks
+  // if a bold underline exists first.
   EXPECT_EQ(gfx::Range(5, 7), model.render_text()->selection());
+  EXPECT_EQ(7U, model.render_text()->cursor_position());
+#else
+  // See SelectRangeInCompositionText().
+  EXPECT_EQ(gfx::Range(7, 5), model.render_text()->selection());
+  EXPECT_EQ(5U, model.render_text()->cursor_position());
+#endif
 
   model.GetTextRange(&range);
   EXPECT_EQ(10U, range.end());
   EXPECT_STR_EQ("1234567890", model.text());
 
   model.GetCompositionTextRange(&range);
   EXPECT_EQ(gfx::Range(5, 8), range);
   // Check the composition text.
   EXPECT_STR_EQ("456", model.GetTextFromRange(gfx::Range(3, 6)));
-  EXPECT_EQ(gfx::Range(5, 7), model.render_text()->selection());

[Yusuke Sato, 2017/05/18 17:14:31]

Removed as this line looked just redundant.

 
   EXPECT_FALSE(composition_text_confirmed_or_cleared_);
   model.CancelCompositionText();
   EXPECT_TRUE(composition_text_confirmed_or_cleared_);
   composition_text_confirmed_or_cleared_ = false;
   EXPECT_FALSE(model.HasCompositionText());
   EXPECT_FALSE(model.HasSelection());
   EXPECT_EQ(5U, model.GetCursorPosition());
 
   model.SetCompositionText(composition);
   EXPECT_STR_EQ("1234567890", model.text());
   EXPECT_TRUE(model.SetText(base::ASCIIToUTF16("1234567890")));
   EXPECT_TRUE(composition_text_confirmed_or_cleared_);
   composition_text_confirmed_or_cleared_ = false;
   model.MoveCursor(gfx::LINE_BREAK, gfx::CURSOR_RIGHT, gfx::SELECTION_NONE);
 
+  composition.selection = gfx::Range(0, 1);

[Yusuke Sato, 2017/05/18 17:14:31]

Added a case where composition.selection exists but a (bold) underline doesn't.

[Shu Chen, 2017/05/21 03:54:30]

nit: pls put this as a code comment.

[Yusuke Sato, 2017/05/22 05:49:00]

Done.

+  composition.underlines.clear();
   model.SetCompositionText(composition);
   EXPECT_STR_EQ("1234567890678", model.text());
+  EXPECT_TRUE(model.HasSelection());
+#if !defined(OS_CHROMEOS)
+  EXPECT_EQ(gfx::Range(10, 11), model.render_text()->selection());
+  EXPECT_EQ(11U, model.render_text()->cursor_position());
+#else
+  // See SelectRangeInCompositionText().
+  EXPECT_EQ(gfx::Range(11, 10), model.render_text()->selection());
+  EXPECT_EQ(10U, model.render_text()->cursor_position());
+#endif
 
   model.InsertText(base::UTF8ToUTF16("-"));
   EXPECT_TRUE(composition_text_confirmed_or_cleared_);
   composition_text_confirmed_or_cleared_ = false;
   EXPECT_STR_EQ("1234567890-", model.text());
   EXPECT_FALSE(model.HasCompositionText());
   EXPECT_FALSE(model.HasSelection());
 
   model.MoveCursor(gfx::CHARACTER_BREAK, gfx::CURSOR_LEFT,
                    gfx::SELECTION_RETAIN);
@@ skipping 807 matching lines @@
   model.Backspace(true);
   model.Backspace(true);
   EXPECT_STR_EQ("aa", model.text());
 
   // Ensure yanking inserts the modified kill buffer text.
   model.Yank();
   EXPECT_STR_EQ("aad", model.text());
 }
 
 }  // namespace views