Use text affinity to return correct accessible line boundaries.

content/browser/accessibility/browser_accessibility_manager_unittest.cc

Index: content/browser/accessibility/browser_accessibility_manager_unittest.cc
diff --git a/content/browser/accessibility/browser_accessibility_manager_unittest.cc b/content/browser/accessibility/browser_accessibility_manager_unittest.cc
index 75342b4edfa565b4714efa2897e9e339576452c4..805edf830ff263f921ea139d475bfbe5ebd68650 100644
--- a/content/browser/accessibility/browser_accessibility_manager_unittest.cc
+++ b/content/browser/accessibility/browser_accessibility_manager_unittest.cc
@@ -1494,4 +1494,51 @@ TEST(BrowserAccessibilityManagerTest, DeletingFocusedNodeDoesNotCrash2) {
   ASSERT_EQ(3, manager->GetFocus()->GetId());
 }
 
+TEST(BrowserAccessibilityManagerTest, LineStartBoundary) {
+  ui::AXNodeData root;
+  root.id = 1;
+  root.role = ui::AX_ROLE_ROOT_WEB_AREA;
+
+  ui::AXNodeData static_text;
+  static_text.id = 2;
+  static_text.SetName("1-2-3-4");
+  static_text.role = ui::AX_ROLE_STATIC_TEXT;
+  root.child_ids.push_back(2);
+
+  ui::AXNodeData inline_text1;
+  inline_text1.id = 3;
+  inline_text1.SetName("1-2-");
+  inline_text1.role = ui::AX_ROLE_INLINE_TEXT_BOX;
+  static_text.child_ids.push_back(3);
+
+  ui::AXNodeData inline_text2;
+  inline_text2.id = 4;
+  inline_text2.SetName("3-4");
+  inline_text2.role = ui::AX_ROLE_INLINE_TEXT_BOX;
+  static_text.child_ids.push_back(4);
+
+  std::unique_ptr<BrowserAccessibilityManager> manager(
+      BrowserAccessibilityManager::Create(
+          MakeAXTreeUpdate(root, static_text, inline_text1, inline_text2),
+          nullptr, new CountedBrowserAccessibilityFactory()));
+
+  BrowserAccessibility* root_accessible = manager->GetRoot();
+  ASSERT_NE(nullptr, root_accessible);
+  BrowserAccessibility* static_text_accessible =
+      root_accessible->PlatformGetChild(0);
+  ASSERT_NE(nullptr, static_text_accessible);
+
+  // If the affinity is downstream, check that we get the second line.
+  ASSERT_EQ(4, static_text_accessible->GetLineStartBoundary(
+      4, ui::BACKWARDS_DIRECTION, ui::AX_TEXT_AFFINITY_DOWNSTREAM));
+  ASSERT_EQ(7, static_text_accessible->GetLineStartBoundary(
+      4, ui::FORWARDS_DIRECTION, ui::AX_TEXT_AFFINITY_DOWNSTREAM));
+
+  // If the affinity is upstream, check that we get the second line.
+  ASSERT_EQ(0, static_text_accessible->GetLineStartBoundary(
+      4, ui::BACKWARDS_DIRECTION, ui::AX_TEXT_AFFINITY_UPSTREAM));
+  ASSERT_EQ(4, static_text_accessible->GetLineStartBoundary(
+      4, ui::FORWARDS_DIRECTION, ui::AX_TEXT_AFFINITY_UPSTREAM));
+}
+
 }  // namespace content