Improve how DocumentMarkerController updates markers in response to text edits

third_party/WebKit/Source/core/editing/markers/DocumentMarkerTest.cpp

Index: third_party/WebKit/Source/core/editing/markers/DocumentMarkerTest.cpp
diff --git a/third_party/WebKit/Source/core/editing/markers/DocumentMarkerTest.cpp b/third_party/WebKit/Source/core/editing/markers/DocumentMarkerTest.cpp
index 6d3f23b8318c17df233ef239c26ab56e6d172e39..c9684a639544927fe56b334090d1c915f92c1b0e 100644
--- a/third_party/WebKit/Source/core/editing/markers/DocumentMarkerTest.cpp
+++ b/third_party/WebKit/Source/core/editing/markers/DocumentMarkerTest.cpp
@@ -8,7 +8,15 @@
 
 namespace blink {
 
-class DocumentMarkerTest : public ::testing::Test {};
+using MarkerOffsets = DocumentMarker::MarkerOffsets;
+
+class DocumentMarkerTest : public ::testing::Test {
+ protected:
+  DocumentMarker* CreateMarker(unsigned startOffset, unsigned endOffset) {
+    return new DocumentMarker(startOffset, endOffset,
+                              DocumentMarker::MatchStatus::kInactive);
+  }
+};
 
 TEST_F(DocumentMarkerTest, MarkerTypeIteratorEmpty) {
   DocumentMarker::MarkerTypes types(0);
@@ -45,4 +53,166 @@ TEST_F(DocumentMarkerTest, MarkerTypeIteratorDistributed) {
   ++it;
   EXPECT_TRUE(it == types.end());
 }
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteAfter) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 0);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(5u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteEndAndAfter) {
+  DocumentMarker* marker = CreateMarker(10, 15);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 0);
+  EXPECT_EQ(10u, result.value().start_offset);
+  EXPECT_EQ(13u, result.value().end_offset);
 }
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteBeforeAndAfter) {
+  DocumentMarker* marker = CreateMarker(20, 25);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 0);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteBeforeAndBeginning) {
+  DocumentMarker* marker = CreateMarker(30, 35);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 0);
+  EXPECT_EQ(13u, result.value().start_offset);
+  EXPECT_EQ(16u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteBefore) {
+  DocumentMarker* marker = CreateMarker(40, 45);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 0);
+  EXPECT_EQ(21u, result.value().start_offset);
+  EXPECT_EQ(26u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteStartAndAfter) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 10, 0);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteBeforeAndEnd) {
+  DocumentMarker* marker = CreateMarker(5, 10);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 10, 0);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteMarkerExactly) {
+  DocumentMarker* marker = CreateMarker(5, 10);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(5, 5, 0);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_DeleteMiddleOfMarker) {
+  DocumentMarker* marker = CreateMarker(5, 10);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(6, 3, 0);
+  EXPECT_EQ(5u, result.value().start_offset);
+  EXPECT_EQ(7u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_InsertAfter) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(10, 0, 5);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(5u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_InsertImmediatelyAfter) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(5, 0, 5);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(5u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_InsertInMiddle) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(2, 0, 5);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(10u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_InsertImmediatelyBefore) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 0, 5);
+  EXPECT_EQ(5u, result.value().start_offset);
+  EXPECT_EQ(10u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_InsertBefore) {
+  DocumentMarker* marker = CreateMarker(5, 10);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 0, 5);
+  EXPECT_EQ(10u, result.value().start_offset);
+  EXPECT_EQ(15u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceAfter) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 1);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(5u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceEndAndAfter) {
+  DocumentMarker* marker = CreateMarker(10, 15);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 1);
+  EXPECT_EQ(10u, result.value().start_offset);
+  EXPECT_EQ(13u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceBeforeAndAfter) {
+  DocumentMarker* marker = CreateMarker(20, 25);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 1);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceBeforeAndBeginning) {
+  DocumentMarker* marker = CreateMarker(30, 35);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 1);
+  EXPECT_EQ(14u, result.value().start_offset);
+  EXPECT_EQ(17u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceBefore) {
+  DocumentMarker* marker = CreateMarker(40, 45);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(13, 19, 1);
+  EXPECT_EQ(22u, result.value().start_offset);
+  EXPECT_EQ(27u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceBeginning) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 2, 1);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(4u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceEnd) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(3, 2, 1);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(4u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceExactly) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 5, 1);
+  EXPECT_EQ(0u, result.value().start_offset);
+  EXPECT_EQ(1u, result.value().end_offset);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceBeginningAndAfter) {
+  DocumentMarker* marker = CreateMarker(0, 5);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(0, 6, 1);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+TEST_F(DocumentMarkerTest, GetShiftedMarkerPosition_ReplaceBeforeAndEnd) {
+  DocumentMarker* marker = CreateMarker(5, 10);
+  Optional<MarkerOffsets> result = marker->ComputeOffsetsAfterShift(4, 6, 1);
+  EXPECT_EQ(WTF::kNullopt, result);
+}
+
+}  // namespace blink