Introduce Position::IsEquivalent()

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

 // Copyright 2015 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/Position.h"
 
 #include "core/editing/EditingTestBase.h"
 
 namespace blink {
 
 class PositionTest : public EditingTestBase {};
 
+TEST_F(PositionTest, IsEquivalent) {
+  SetBodyContent("<a id=sample>0<b>1</b>2</a>");
+
+  Element* sample = GetDocument().getElementById("sample");
+
+  EXPECT_TRUE(Position(sample, 0).IsEquivalent(Position(sample, 0)));
+
+  EXPECT_TRUE(
+      Position(sample, 0).IsEquivalent(Position::FirstPositionInNode(sample)));
+  EXPECT_TRUE(Position(sample, 0).IsEquivalent(
+      Position::BeforeNode(sample->firstChild())));
+  EXPECT_TRUE(Position(sample, 1).IsEquivalent(
+      Position::AfterNode(sample->firstChild())));
+  EXPECT_TRUE(Position(sample, 1).IsEquivalent(
+      Position::BeforeNode(sample->firstChild()->nextSibling())));
+  EXPECT_TRUE(Position(sample, 2).IsEquivalent(
+      Position::BeforeNode(sample->lastChild())));
+  EXPECT_TRUE(Position(sample, 3).IsEquivalent(
+      Position::AfterNode(sample->lastChild())));
+  EXPECT_TRUE(
+      Position(sample, 3).IsEquivalent(Position::LastPositionInNode(sample)));
+
+  EXPECT_FALSE(Position(sample, 0).IsEquivalent(Position(sample, 1)));
+  EXPECT_FALSE(
+      Position(sample, 0).IsEquivalent(Position::LastPositionInNode(sample)));
+}
+
 TEST_F(PositionTest, NodeAsRangeLastNodeNull) {
   EXPECT_EQ(nullptr, Position().NodeAsRangeLastNode());
   EXPECT_EQ(nullptr, PositionInFlatTree().NodeAsRangeLastNode());
 }
 
 TEST_F(PositionTest, editingPositionOfWithEditingIgnoresContent) {
   const char* body_content =
       "<textarea id=textarea></textarea><a id=child1>1</a><b id=child2>2</b>";
   SetBodyContent(body_content);
   Node* textarea = GetDocument().getElementById("textarea");
@@ skipping 172 matching lines @@
   const char* shadow_content = "";
   SetBodyContent(body_content);
   ShadowRoot* shadow_root = SetShadowContent(shadow_content, "host");
   Element* host = GetDocument().getElementById("host");
 
   EXPECT_EQ(PositionInFlatTree(host, PositionAnchorType::kAfterChildren),
             ToPositionInFlatTree(Position(shadow_root, 0)));
 }
 
 }  // namespace blink