1 files changed, 264 insertions, 0 deletions
diff --git a/chromium/third_party/blink/renderer/modules/accessibility/testing/accessibility_selection_test.cc b/chromium/third_party/blink/renderer/modules/accessibility/testing/accessibility_selection_test.cc
new file mode 100644
index 00000000000..9a91e8f4d82
--- /dev/null
+++ b/chromium/third_party/blink/renderer/modules/accessibility/testing/accessibility_selection_test.cc
@@ -0,0 +1,264 @@
+// Copyright 2018 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 "third_party/blink/renderer/modules/accessibility/testing/accessibility_selection_test.h"
+
+#include "third_party/blink/renderer/core/dom/node.h"
+#include "third_party/blink/renderer/core/html/html_element.h"
+#include "third_party/blink/renderer/modules/accessibility/ax_object.h"
+#include "third_party/blink/renderer/modules/accessibility/ax_object_cache_impl.h"
+#include "third_party/blink/renderer/modules/accessibility/ax_position.h"
+#include "third_party/blink/renderer/modules/accessibility/ax_selection.h"
+#include "third_party/blink/renderer/platform/heap/handle.h"
+#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
+#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
+
+namespace blink {
+
+namespace {
+
+// Serialize accessibility subtree to selection text.
+// Adds a '^' at the selection anchor offset and a '|' at the focus offset.
+class AXSelectionSerializer final {
+  STACK_ALLOCATED();
+
+ public:
+  explicit AXSelectionSerializer(const AXSelection& selection)
+      : selection_(selection) {}
+
+  std::string Serialize(const AXObject& subtree) {
+    if (!selection_.IsValid())
+      return {};
+    SerializeSubtree(subtree);
+    return builder_.ToString().Utf8().data();
+  }
+
+ private:
+  void HandleTextObject(const AXObject& text_object) {
+    builder_.Append('<');
+    builder_.Append(AXObject::InternalRoleName(text_object.RoleValue()));
+    builder_.Append(": ");
+    const String name = text_object.ComputedName() + '>';
+    const AXObject& base_container = *selection_.Base().ContainerObject();
+    const AXObject& extent_container = *selection_.Extent().ContainerObject();
+
+    if (base_container == text_object && extent_container == text_object) {
+      DCHECK(selection_.Base().IsTextPosition() &&
+             selection_.Extent().IsTextPosition());
+      const int base_offset = selection_.Base().TextOffset();
+      const int extent_offset = selection_.Extent().TextOffset();
+
+      if (base_offset == extent_offset) {
+        builder_.Append(name.Left(base_offset));
+        builder_.Append('|');
+        builder_.Append(name.Substring(base_offset));
+        return;
+      }
+
+      if (base_offset < extent_offset) {
+        builder_.Append(name.Left(base_offset));
+        builder_.Append('^');
+        builder_.Append(
+            name.Substring(base_offset, extent_offset - base_offset));
+        builder_.Append('|');
+        builder_.Append(name.Substring(extent_offset));
+        return;
+      }
+
+      builder_.Append(name.Left(extent_offset));
+      builder_.Append('|');
+      builder_.Append(
+          name.Substring(extent_offset, base_offset - extent_offset));
+      builder_.Append('^');
+      builder_.Append(name.Substring(base_offset));
+      return;
+    }
+
+    if (base_container == text_object) {
+      DCHECK(selection_.Base().IsTextPosition());
+      const int base_offset = selection_.Base().TextOffset();
+
+      builder_.Append(name.Left(base_offset));
+      builder_.Append('^');
+      builder_.Append(name.Substring(base_offset));
+      return;
+    }
+
+    if (extent_container == text_object) {
+      DCHECK(selection_.Extent().IsTextPosition());
+      const int extent_offset = selection_.Extent().TextOffset();
+
+      builder_.Append(name.Left(extent_offset));
+      builder_.Append('|');
+      builder_.Append(name.Substring(extent_offset));
+      return;
+    }
+
+    builder_.Append(name);
+  }
+
+  void HandleObject(const AXObject& object) {
+    builder_.Append('<');
+    builder_.Append(AXObject::InternalRoleName(object.RoleValue()));
+    builder_.Append(": ");
+    builder_.Append(object.ComputedName());
+    builder_.Append('>');
+    SerializeSubtree(object);
+  }
+
+  void HandleSelection(const AXPosition& position) {
+    if (!position.IsValid())
+      return;
+
+    if (selection_.Extent() == position) {
+      builder_.Append('|');
+      return;
+    }
+
+    if (selection_.Base() != position)
+      return;
+
+    builder_.Append('^');
+  }
+
+  void SerializeSubtree(const AXObject& subtree) {
+    for (const Member<AXObject>& child : subtree.Children()) {
+      if (!child)
+        continue;
+      const auto position = AXPosition::CreatePositionBeforeObject(*child);
+      HandleSelection(position);
+      if (position.IsTextPosition()) {
+        HandleTextObject(*child);
+      } else {
+        HandleObject(*child);
+      }
+    }
+    HandleSelection(AXPosition::CreateLastPositionInObject(subtree));
+  }
+
+  StringBuilder builder_;
+  AXSelection selection_;
+};
+
+// Deserializes an HTML snippet with or without selection markers to an
+// accessibility tree. A '^' could be present at the selection anchor offset and
+// a '|' at the focus offset. If multiple markers are present, the deserializer
+// will DCHECK. If there are no markers, no selection will be made.
+class AXSelectionDeserializer final {
+  STACK_ALLOCATED();
+
+ public:
+  AXSelectionDeserializer(AXObjectCacheImpl& cache)
+      : ax_object_cache_(&cache), base_(), extent_() {}
+  ~AXSelectionDeserializer() = default;
+
+  // Creates an accessibility tree rooted at the given HTML element from the
+  // provided HTML snippet, selects the part of the tree indicated by the
+  // selection markers in the snippet if present, and returns the tree's root.
+  AXObject* Deserialize(const std::string& html_snippet, HTMLElement& element) {
+    element.SetInnerHTMLFromString(String::FromUTF8(html_snippet.c_str()));
+    AXObject* root = ax_object_cache_->GetOrCreate(&element);
+    if (!root)
+      return nullptr;
+
+    FindSelectionMarkers(*root);
+    if (base_ && extent_) {
+      AXSelection::Builder builder;
+      AXSelection ax_selection =
+          builder.SetBase(base_).SetExtent(extent_).Build();
+      ax_selection.Select();
+    }
+
+    return root;
+  }
+
+ private:
+  void HandleCharacterData(const AXObject& text_object) {
+    int base_offset = -1;
+    int extent_offset = -1;
+    String name = text_object.ComputedName();
+    for (unsigned i = 0; i < name.length(); ++i) {
+      const UChar character = name[i];
+      if (character == '^') {
+        DCHECK_EQ(base_offset, -1) << text_object;
+        base_offset = static_cast<int>(i);
+        continue;
+      }
+      if (character == '|') {
+        DCHECK_EQ(extent_offset, -1) << text_object;
+        extent_offset = static_cast<int>(i);
+        continue;
+      }
+    }
+
+    if (base_offset == -1 && extent_offset == -1)
+      return;
+
+    if (base_offset >= 0)
+      base_ = AXPosition::CreatePositionInTextObject(text_object, base_offset);
+    if (extent_offset >= 0) {
+      extent_ =
+          AXPosition::CreatePositionInTextObject(text_object, extent_offset);
+    }
+  }
+
+  void HandleObject(const AXObject& object) {
+    for (const Member<AXObject>& child : object.Children()) {
+      if (!child)
+        continue;
+      FindSelectionMarkers(*child);
+    }
+  }
+
+  void FindSelectionMarkers(const AXObject& root) {
+    const Node* node = root.GetNode();
+    if (node && node->IsCharacterDataNode()) {
+      HandleCharacterData(root);
+      return;
+    }
+    HandleObject(root);
+  }
+
+  Member<AXObjectCacheImpl> const ax_object_cache_;
+  AXPosition base_;
+  AXPosition extent_;
+};
+
+}  // namespace
+
+AccessibilitySelectionTest::AccessibilitySelectionTest(
+    LocalFrameClient* local_frame_client)
+    : AccessibilityTest(local_frame_client) {}
+
+std::string AccessibilitySelectionTest::GetSelectionText(
+    const AXSelection& selection) const {
+  const AXObject* root = GetAXRootObject();
+  if (!root)
+    return {};
+  return AXSelectionSerializer(selection).Serialize(*root);
+}
+
+std::string AccessibilitySelectionTest::GetSelectionText(
+    const AXSelection& selection,
+    const AXObject& subtree) const {
+  return AXSelectionSerializer(selection).Serialize(subtree);
+}
+
+AXObject* AccessibilitySelectionTest::SetSelectionText(
+    const std::string& selection_text) const {
+  HTMLElement* body = GetDocument().body();
+  if (!body)
+    return nullptr;
+  return AXSelectionDeserializer(GetAXObjectCache())
+      .Deserialize(selection_text, *body);
+}
+
+AXObject* AccessibilitySelectionTest::SetSelectionText(
+    const std::string& selection_text,
+    HTMLElement& element) const {
+  return AXSelectionDeserializer(GetAXObjectCache())
+      .Deserialize(selection_text, element);
+}
+
+}  // namespace blink