Fix focus navigation for nested slot case

third_party/WebKit/Source/core/dom/shadow/SlotScopedTraversalTest.cpp

Index: third_party/WebKit/Source/core/dom/shadow/SlotScopedTraversalTest.cpp
diff --git a/third_party/WebKit/Source/core/dom/shadow/SlotScopedTraversalTest.cpp b/third_party/WebKit/Source/core/dom/shadow/SlotScopedTraversalTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..fa3e4d6703ac0bf92e00b35f47242cd65ea13d5b
--- /dev/null
+++ b/third_party/WebKit/Source/core/dom/shadow/SlotScopedTraversalTest.cpp
@@ -0,0 +1,411 @@
+// Copyright 2016 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 "core/dom/shadow/SlotScopedTraversal.h"
+
+#include "bindings/core/v8/ExceptionStatePlaceholder.h"
+#include "core/dom/Document.h"
+#include "core/dom/Element.h"
+#include "core/dom/Node.h"
+#include "core/dom/NodeTraversal.h"
+#include "core/dom/shadow/ShadowRoot.h"
+#include "core/html/HTMLElement.h"
+#include "core/html/HTMLSlotElement.h"
+#include "core/testing/DummyPageHolder.h"
+#include "platform/geometry/IntSize.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "wtf/Vector.h"
+#include <memory>
+
+namespace blink {
+
+class SlotScopedTraversalTest : public ::testing::Test {
+ protected:
+  Document& document() const;
+
+  void setupSampleHTML(const char* mainHTML, const char* shadowHTML, unsigned);
+  void attachOpenShadowRoot(Element& shadowHost, const char* shadowInnerHTML);
+  void testExpectedSequence(const Vector<Element*>& list);
+
+ private:
+  void SetUp() override;
+
+  Persistent<Document> m_document;
+  std::unique_ptr<DummyPageHolder> m_dummyPageHolder;
+};
+
+void SlotScopedTraversalTest::SetUp() {
+  m_dummyPageHolder = DummyPageHolder::create(IntSize(800, 600));
+  m_document = &m_dummyPageHolder->document();
+  DCHECK(m_document);
+}
+
+Document& SlotScopedTraversalTest::document() const {
+  return *m_document;
+}
+
+void SlotScopedTraversalTest::setupSampleHTML(const char* mainHTML,
+                                              const char* shadowHTML,
+                                              unsigned index) {
+  Element* body = document().body();
+  body->setInnerHTML(String::fromUTF8(mainHTML), ASSERT_NO_EXCEPTION);
+  if (shadowHTML) {
+    Element* shadowHost = toElement(NodeTraversal::childAt(*body, index));
+    attachOpenShadowRoot(*shadowHost, shadowHTML);
+  }
+}
+
+void SlotScopedTraversalTest::attachOpenShadowRoot(
+    Element& shadowHost,
+    const char* shadowInnerHTML) {
+  ShadowRoot* shadowRoot = shadowHost.createShadowRootInternal(
+      ShadowRootType::Open, ASSERT_NO_EXCEPTION);
+  shadowRoot->setInnerHTML(String::fromUTF8(shadowInnerHTML),
+                           ASSERT_NO_EXCEPTION);
+  document().body()->updateDistribution();
+}
+
+TEST_F(SlotScopedTraversalTest, emptySlot) {
+  const char* mainHTML = "<div id='host'></div>";
+  const char* shadowHTML = "<slot></slot>";
+  setupSampleHTML(mainHTML, shadowHTML, 0);
+
+  Element* host = document().querySelector("#host");
+  ShadowRoot* shadowRoot = host->openShadowRoot();
+  Element* slotElement = shadowRoot->querySelector("slot");
+  DCHECK(isHTMLSlotElement(slotElement));
+  HTMLSlotElement* slot = toHTMLSlotElement(slotElement);
+
+  EXPECT_EQ(nullptr, SlotScopedTraversal::firstAssignedToSlot(*slot));
+  EXPECT_EQ(nullptr, SlotScopedTraversal::lastAssignedToSlot(*slot));
+}
+
+void SlotScopedTraversalTest::testExpectedSequence(
+    const Vector<Element*>& list) {
+  for (size_t i = 0; i < list.size(); ++i) {
+    const Element* expected = i == list.size() - 1 ? nullptr : list[i + 1];
+    EXPECT_EQ(expected, SlotScopedTraversal::next(*list[i]));
+  }
+
+  for (size_t i = list.size(); i > 0; --i) {
+    const Element* expected = i == 1 ? nullptr : list[i - 2];
+    EXPECT_EQ(expected, SlotScopedTraversal::previous(*list[i - 1]));
+  }
+}
+
+TEST_F(SlotScopedTraversalTest, simpleSlot) {
+  const char* mainHTML =
+      "<div id='host'>"
+      "<div id='inner1'></div>"
+      "<div id='inner2'></div>"
+      "</div>";
+
+  const char* shadowHTML = "<slot></slot>";
+
+  setupSampleHTML(mainHTML, shadowHTML, 0);
+
+  Element* host = document().querySelector("#host");
+  Element* inner1 = document().querySelector("#inner1");
+  Element* inner2 = document().querySelector("#inner2");
+  ShadowRoot* shadowRoot = host->openShadowRoot();
+  Element* slotElement = shadowRoot->querySelector("slot");
+  DCHECK(isHTMLSlotElement(slotElement));
+  HTMLSlotElement* slot = toHTMLSlotElement(slotElement);
+
+  EXPECT_EQ(inner1, SlotScopedTraversal::firstAssignedToSlot(*slot));
+  EXPECT_EQ(inner2, SlotScopedTraversal::lastAssignedToSlot(*slot));
+  EXPECT_FALSE(SlotScopedTraversal::isSlotScoped(*host));
+  EXPECT_FALSE(SlotScopedTraversal::isSlotScoped(*slot));
+  EXPECT_TRUE(SlotScopedTraversal::isSlotScoped(*inner1));
+  EXPECT_TRUE(SlotScopedTraversal::isSlotScoped(*inner2));
+  EXPECT_EQ(inner1, SlotScopedTraversal::nearestInclusiveAncestorAssignedToSlot(
+                        *inner1));
+  EXPECT_EQ(inner2, SlotScopedTraversal::nearestInclusiveAncestorAssignedToSlot(
+                        *inner2));
+  EXPECT_EQ(slot, SlotScopedTraversal::findScopeOwnerSlot(*inner1));
+  EXPECT_EQ(slot, SlotScopedTraversal::findScopeOwnerSlot(*inner2));
+
+  Vector<Element*> expectedSequence({inner1, inner2});
+  testExpectedSequence(expectedSequence);
+}
+
+TEST_F(SlotScopedTraversalTest, multipleSlots) {
+  const char* mainHTML =
+      "<div id='host'>"
+      "<div id='inner0' slot='slot0'></div>"
+      "<div id='inner1' slot='slot1'></div>"
+      "<div id='inner2'></div>"
+      "<div id='inner3' slot='slot1'></div>"
+      "<div id='inner4' slot='slot0'></div>"
+      "<div id='inner5'></div>"
+      "</div>";
+
+  const char* shadowHTML =
+      "<slot id='unnamedslot'></slot>"
+      "<slot id='slot0' name='slot0'></slot>"
+      "<slot id='slot1' name='slot1'></slot>";
+
+  setupSampleHTML(mainHTML, shadowHTML, 0);
+
+  Element* host = document().querySelector("#host");
+  Element* inner[6];
+  inner[0] = document().querySelector("#inner0");
+  inner[1] = document().querySelector("#inner1");
+  inner[2] = document().querySelector("#inner2");
+  inner[3] = document().querySelector("#inner3");
+  inner[4] = document().querySelector("#inner4");
+  inner[5] = document().querySelector("#inner5");
+
+  ShadowRoot* shadowRoot = host->openShadowRoot();
+  Element* slotElement[3];
+  slotElement[0] = shadowRoot->querySelector("#slot0");
+  slotElement[1] = shadowRoot->querySelector("#slot1");
+  slotElement[2] = shadowRoot->querySelector("#unnamedslot");
+
+  HTMLSlotElement* slot[3];
+  slot[0] = toHTMLSlotElement(slotElement[0]);
+  slot[1] = toHTMLSlotElement(slotElement[1]);
+  slot[2] = toHTMLSlotElement(slotElement[2]);
+
+  {
+    // <slot id='slot0'> : Expected assigned nodes: inner0, inner4
+    EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot[0]));
+    EXPECT_EQ(inner[4], SlotScopedTraversal::lastAssignedToSlot(*slot[0]));
+    Vector<Element*> expectedSequence({inner[0], inner[4]});
+    testExpectedSequence(expectedSequence);
+  }
+
+  {
+    // <slot name='slot1'> : Expected assigned nodes: inner1, inner3
+    EXPECT_EQ(inner[1], SlotScopedTraversal::firstAssignedToSlot(*slot[1]));
+    EXPECT_EQ(inner[3], SlotScopedTraversal::lastAssignedToSlot(*slot[1]));
+    Vector<Element*> expectedSequence({inner[1], inner[3]});
+    testExpectedSequence(expectedSequence);
+  }
+
+  {
+    // <slot id='unnamedslot'> : Expected assigned nodes: inner2, inner5
+    EXPECT_EQ(inner[2], SlotScopedTraversal::firstAssignedToSlot(*slot[2]));
+    EXPECT_EQ(inner[5], SlotScopedTraversal::lastAssignedToSlot(*slot[2]));
+    Vector<Element*> expectedSequence({inner[2], inner[5]});
+    testExpectedSequence(expectedSequence);
+  }
+}
+
+TEST_F(SlotScopedTraversalTest, shadowHostAtTopLevel) {
+  // This covers a shadow host is directly assigned to a slot.
+  //
+  // We build the following tree:
+  //         host
+  //           |
+  //       ShadowRoot
+  //           |
+  //     ____<slot>____
+  //     |      |      |
+  //   inner0 inner1 inner2
+  //     |      |      |
+  //   child0 child1 child2
+  //
+  // And iterate on inner0, inner1, and inner2 to attach shadow on each of
+  // them, and check if elements that are slotted to another slot are skipped
+  // in traversal.
+
+  const char* mainHTML =
+      "<div id='host'>"
+      "<div id='inner0'><div id='child0'></div></div>"
+      "<div id='inner1'><div id='child1'></div></div>"
+      "<div id='inner2'><div id='child2'></div></div>"
+      "</div>";
+
+  const char* shadowHTML = "<slot></slot>";
+
+  for (int i = 0; i < 3; ++i) {
+    setupSampleHTML(mainHTML, shadowHTML, 0);
+
+    Element* host = document().querySelector("#host");
+    Element* inner[3];
+    inner[0] = document().querySelector("#inner0");
+    inner[1] = document().querySelector("#inner1");
+    inner[2] = document().querySelector("#inner2");
+    Element* child[3];
+    child[0] = document().querySelector("#child0");
+    child[1] = document().querySelector("#child1");
+    child[2] = document().querySelector("#child2");
+
+    attachOpenShadowRoot(*inner[i], shadowHTML);
+
+    ShadowRoot* shadowRoot = host->openShadowRoot();
+    Element* slotElement = shadowRoot->querySelector("slot");
+    DCHECK(isHTMLSlotElement(slotElement));
+    HTMLSlotElement* slot = toHTMLSlotElement(slotElement);
+
+    switch (i) {
+      case 0: {
+        // inner0 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(child[2], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*child[0]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*child[0]));
+
+        Vector<Element*> expectedSequence(
+            {inner[0], inner[1], child[1], inner[2], child[2]});
+        testExpectedSequence(expectedSequence);
+      } break;
+
+      case 1: {
+        // inner1 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(child[2], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*child[1]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*child[1]));
+
+        Vector<Element*> expectedSequence(
+            {inner[0], child[0], inner[1], inner[2], child[2]});
+        testExpectedSequence(expectedSequence);
+      } break;
+
+      case 2: {
+        // inner2 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(inner[2], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*child[2]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*child[2]));
+
+        Vector<Element*> expectedSequence(
+            {inner[0], child[0], inner[1], child[1], inner[2]});
+        testExpectedSequence(expectedSequence);
+      } break;
+    }
+  }
+}
+
+TEST_F(SlotScopedTraversalTest, shadowHostAtSecondLevel) {
+  // This covers cases where a shadow host exists in a child of a slotted
+  // element.
+  //
+  // We build the following tree:
+  //            host
+  //              |
+  //          ShadowRoot
+  //              |
+  //        ____<slot>____
+  //        |             |
+  //     _inner0_      _inner1_
+  //     |      |      |      |
+  //   child0 child1 child2 child3
+  //     |      |      |      |
+  //    span0  span1  span2  span3
+  //
+  // And iterate on child0, child1, child2, and child3 to attach shadow on each
+  // of them, and check if elements that are slotted to another slot are skipped
+  // in traversal.
+
+  const char* mainHTML =
+      "<div id='host'>"
+      "<div id='inner0'>"
+      "<div id='child0'><span id='span0'></span></div>"
+      "<div id='child1'><span id='span1'></span></div>"
+      "</div>"
+      "<div id='inner1'>"
+      "<div id='child2'><span id='span2'></span></div>"
+      "<div id='child3'><span id='span3'></span></div>"
+      "</div>"
+      "</div>";
+
+  const char* shadowHTML = "<slot></slot>";
+
+  for (int i = 0; i < 4; ++i) {
+    setupSampleHTML(mainHTML, shadowHTML, 0);
+
+    Element* host = document().querySelector("#host");
+    Element* inner[2];
+    inner[0] = document().querySelector("#inner0");
+    inner[1] = document().querySelector("#inner1");
+    Element* child[4];
+    child[0] = document().querySelector("#child0");
+    child[1] = document().querySelector("#child1");
+    child[2] = document().querySelector("#child2");
+    child[3] = document().querySelector("#child3");
+    Element* span[4];
+    span[0] = document().querySelector("#span0");
+    span[1] = document().querySelector("#span1");
+    span[2] = document().querySelector("#span2");
+    span[3] = document().querySelector("#span3");
+
+    attachOpenShadowRoot(*child[i], shadowHTML);
+
+    for (int j = 0; j < 4; ++j) {
+      DCHECK(child[i]);
+      DCHECK(span[i]);
+    }
+
+    ShadowRoot* shadowRoot = host->openShadowRoot();
+    Element* slotElement = shadowRoot->querySelector("slot");
+    DCHECK(isHTMLSlotElement(slotElement));
+    HTMLSlotElement* slot = toHTMLSlotElement(slotElement);
+
+    switch (i) {
+      case 0: {
+        // child0 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(span[3], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*span[0]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*span[0]));
+
+        const Vector<Element*> expectedSequence({inner[0], child[0], child[1],
+                                                 span[1], inner[1], child[2],
+                                                 span[2], child[3], span[3]});
+        testExpectedSequence(expectedSequence);
+      } break;
+
+      case 1: {
+        // child1 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(span[3], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*span[1]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*span[1]));
+
+        const Vector<Element*> expectedSequence({inner[0], child[0], span[0],
+                                                 child[1], inner[1], child[2],
+                                                 span[2], child[3], span[3]});
+        testExpectedSequence(expectedSequence);
+      } break;
+
+      case 2: {
+        // child2 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(span[3], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*span[2]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*span[2]));
+
+        const Vector<Element*> expectedSequence({inner[0], child[0], span[0],
+                                                 child[1], span[1], inner[1],
+                                                 child[2], child[3], span[3]});
+        testExpectedSequence(expectedSequence);
+      } break;
+
+      case 3: {
+        // child3 is a shadow host.
+        EXPECT_EQ(inner[0], SlotScopedTraversal::firstAssignedToSlot(*slot));
+        EXPECT_EQ(child[3], SlotScopedTraversal::lastAssignedToSlot(*slot));
+
+        EXPECT_EQ(nullptr, SlotScopedTraversal::next(*span[3]));
+        EXPECT_EQ(nullptr, SlotScopedTraversal::previous(*span[3]));
+
+        const Vector<Element*> expectedSequence({inner[0], child[0], span[0],
+                                                 child[1], span[1], inner[1],
+                                                 child[2], span[2], child[3]});
+        testExpectedSequence(expectedSequence);
+      } break;
+    }
+  }
+}
+
+}  // namespace blink