[PDF Ink Signatures] Add EraseStrokesAcrossTwoPages test

Add PdfInkModuleStrokeTest.EraseStrokesAcrossTwoPages to check an eraser
stroke across two pages erases strokes on both pages.

Bug: 352720912
Change-Id: I377c18509ebabb498d71b25d7e3b03e746ccf812
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5787686
Reviewed-by: Andy Phan <andyphan@chromium.org>
Reviewed-by: Alan Screen <awscreen@chromium.org>
Code-Coverage: findit-for-me@appspot.gserviceaccount.com <findit-for-me@appspot.gserviceaccount.com>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1343087}

pdf/pdf_ink_module_unittest.cc

@@ -38,6 +38,7 @@ using testing::ElementsAre;
 using testing::ElementsAreArray;
 using testing::InSequence;
 using testing::Pair;
+using testing::SizeIs;
 
 namespace chrome_pdf {
 
@@ -598,7 +599,7 @@ TEST_F(PdfInkModuleStrokeTest, StrokeInsidePages) {
       base::span_from_ref(kTwoPageVerticalLayoutPoint2InsidePage0),
       kTwoPageVerticalLayoutPoint3InsidePage0);
 
-  EXPECT_THAT(StrokeInputPositions(), ElementsAre(Pair(0, testing::SizeIs(1))));
+  EXPECT_THAT(StrokeInputPositions(), ElementsAre(Pair(0, SizeIs(1))));
 
   // A stroke in the second page generates a stroke only for that page.
   ApplyStrokeWithMouseAtPoints(
@@ -606,8 +607,8 @@ TEST_F(PdfInkModuleStrokeTest, StrokeInsidePages) {
       base::span_from_ref(kTwoPageVerticalLayoutPoint2InsidePage1),
       kTwoPageVerticalLayoutPoint3InsidePage1);
 
-  EXPECT_THAT(StrokeInputPositions(), ElementsAre(Pair(0, testing::SizeIs(1)),
-                                                  Pair(1, testing::SizeIs(1))));
+  EXPECT_THAT(StrokeInputPositions(),
+              ElementsAre(Pair(0, SizeIs(1)), Pair(1, SizeIs(1))));
 }
 
 TEST_F(PdfInkModuleStrokeTest, StrokeAcrossPages) {
@@ -624,7 +625,7 @@ TEST_F(PdfInkModuleStrokeTest, StrokeAcrossPages) {
       base::span_from_ref(kTwoPageVerticalLayoutPoint2InsidePage1),
       kTwoPageVerticalLayoutPoint3InsidePage1);
 
-  EXPECT_THAT(StrokeInputPositions(), ElementsAre(Pair(0, testing::SizeIs(1))));
+  EXPECT_THAT(StrokeInputPositions(), ElementsAre(Pair(0, SizeIs(1))));
 }
 
 TEST_F(PdfInkModuleStrokeTest, StrokePageExitAndReentry) {
@@ -777,6 +778,42 @@ TEST_F(PdfInkModuleStrokeTest, EraseStrokeErasesTwoStrokes) {
   EXPECT_EQ(3, client().stroke_finished_count());
 }
 
+TEST_F(PdfInkModuleStrokeTest, EraseStrokesAcrossTwoPages) {
+  EnableAnnotationMode();
+  InitializeVerticalTwoPageLayout();
+
+  // Start out without any strokes.
+  EXPECT_TRUE(StrokeInputPositions().empty());
+  EXPECT_EQ(0, client().stroke_finished_count());
+
+  // A stroke in the first page generates a stroke only for that page.
+  ApplyStrokeWithMouseAtPoints(
+      kTwoPageVerticalLayoutPoint1InsidePage0,
+      base::span_from_ref(kTwoPageVerticalLayoutPoint2InsidePage0),
+      kTwoPageVerticalLayoutPoint3InsidePage0);
+  EXPECT_THAT(StrokeInputPositions(), ElementsAre(Pair(0, SizeIs(1))));
+  EXPECT_EQ(1, client().stroke_finished_count());
+
+  // A stroke in the second page generates a stroke only for that page.
+  ApplyStrokeWithMouseAtPoints(
+      kTwoPageVerticalLayoutPoint1InsidePage1,
+      base::span_from_ref(kTwoPageVerticalLayoutPoint2InsidePage1),
+      kTwoPageVerticalLayoutPoint3InsidePage1);
+  EXPECT_THAT(StrokeInputPositions(),
+              ElementsAre(Pair(0, SizeIs(1)), Pair(1, SizeIs(1))));
+  EXPECT_EQ(2, client().stroke_finished_count());
+
+  // Erasing across the two pages should erase everything.
+  SelectEraserTool();
+  ApplyStrokeWithMouseAtPoints(
+      kTwoPageVerticalLayoutPoint1InsidePage0,
+      std::vector<gfx::PointF>{kTwoPageVerticalLayoutPoint2InsidePage0,
+                               kTwoPageVerticalLayoutPoint1InsidePage1},
+      kTwoPageVerticalLayoutPoint3InsidePage1);
+  EXPECT_TRUE(VisibleStrokeInputPositions().empty());
+  EXPECT_EQ(3, client().stroke_finished_count());
+}
+
 TEST_F(PdfInkModuleStrokeTest, EraseStrokePageExitAndReentry) {
   EnableAnnotationMode();
   InitializeVerticalTwoPageLayout();