Introduce Position::IsEquivalent()

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

Index: third_party/WebKit/Source/core/editing/PositionTest.cpp
diff --git a/third_party/WebKit/Source/core/editing/PositionTest.cpp b/third_party/WebKit/Source/core/editing/PositionTest.cpp
index 2d947238f576820d96a6b3c037613b1eb98b87ff..220bb434e5386b4a4d8e753ce79e4b329950a9bb 100644
--- a/third_party/WebKit/Source/core/editing/PositionTest.cpp
+++ b/third_party/WebKit/Source/core/editing/PositionTest.cpp
@@ -10,6 +10,33 @@ namespace blink {
 
 class PositionTest : public EditingTestBase {};
 
+TEST_F(PositionTest, IsEquivalent) {
+  SetBodyContent("<a id=sample>0<b>1</b>2</b>");

[hugoh_UTC2, 2017/05/12 14:12:14]

<b>2</b> ?

Missing </a> ?

[yosin_UTC9, 2017/05/15 04:08:15]

Good catch. It should be "</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());