Only allow one shadowRoot.

sky/engine/core/dom/TreeScopeTest.cpp

 // Copyright 2014 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 "sky/engine/config.h"
 #include "sky/engine/core/dom/TreeScope.h"
 
 #include <gtest/gtest.h>
 #include "sky/engine/core/dom/Document.h"
 #include "sky/engine/core/dom/Element.h"
 #include "sky/engine/core/dom/shadow/ShadowRoot.h"
 
 using namespace blink;
 
 namespace {
 
 TEST(TreeScopeTest, CommonAncestorOfSameTrees)
 {
     RefPtr<Document> document = Document::create();
     EXPECT_EQ(document.get(), document->commonAncestorTreeScope(*document));
 
     RefPtr<Element> html = document->createElement("html", nullAtom, ASSERT_NO_EXCEPTION);
     document->appendChild(html, ASSERT_NO_EXCEPTION);
-    RefPtr<ShadowRoot> shadowRoot = html->createShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRoot = html->ensureShadowRoot(ASSERT_NO_EXCEPTION);
     EXPECT_EQ(shadowRoot.get(), shadowRoot->commonAncestorTreeScope(*shadowRoot));
 }
 
 TEST(TreeScopeTest, CommonAncestorOfInclusiveTrees)
 {
     //  document
     //     |      : Common ancestor is document.
     // shadowRoot
 
     RefPtr<Document> document = Document::create();
     RefPtr<Element> html = document->createElement("html", nullAtom, ASSERT_NO_EXCEPTION);
     document->appendChild(html, ASSERT_NO_EXCEPTION);
-    RefPtr<ShadowRoot> shadowRoot = html->createShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRoot = html->ensureShadowRoot(ASSERT_NO_EXCEPTION);
 
     EXPECT_EQ(document.get(), document->commonAncestorTreeScope(*shadowRoot));
     EXPECT_EQ(document.get(), shadowRoot->commonAncestorTreeScope(*document));
 }
 
 TEST(TreeScopeTest, CommonAncestorOfSiblingTrees)
 {
     //  document
     //   /    \  : Common ancestor is document.
     //  A      B
 
     RefPtr<Document> document = Document::create();
     RefPtr<Element> html = document->createElement("html", nullAtom, ASSERT_NO_EXCEPTION);
     document->appendChild(html, ASSERT_NO_EXCEPTION);
     RefPtr<Element> head = document->createElement("head", nullAtom, ASSERT_NO_EXCEPTION);
     html->appendChild(head);
     RefPtr<Element> body = document->createElement("body", nullAtom, ASSERT_NO_EXCEPTION);
     html->appendChild(body);
 
-    RefPtr<ShadowRoot> shadowRootA = head->createShadowRoot(ASSERT_NO_EXCEPTION);
-    RefPtr<ShadowRoot> shadowRootB = body->createShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRootA = head->ensureShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRootB = body->ensureShadowRoot(ASSERT_NO_EXCEPTION);
 
     EXPECT_EQ(document.get(), shadowRootA->commonAncestorTreeScope(*shadowRootB));
     EXPECT_EQ(document.get(), shadowRootB->commonAncestorTreeScope(*shadowRootA));
 }
 
 TEST(TreeScopeTest, CommonAncestorOfTreesAtDifferentDepths)
 {
     //  document
     //    / \    : Common ancestor is document.
     //   Y   B
     //  /
     // A
 
     RefPtr<Document> document = Document::create();
     RefPtr<Element> html = document->createElement("html", nullAtom, ASSERT_NO_EXCEPTION);
     document->appendChild(html, ASSERT_NO_EXCEPTION);
     RefPtr<Element> head = document->createElement("head", nullAtom, ASSERT_NO_EXCEPTION);
     html->appendChild(head);
     RefPtr<Element> body = document->createElement("body", nullAtom, ASSERT_NO_EXCEPTION);
     html->appendChild(body);
 
-    RefPtr<ShadowRoot> shadowRootY = head->createShadowRoot(ASSERT_NO_EXCEPTION);
-    RefPtr<ShadowRoot> shadowRootB = body->createShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRootY = head->ensureShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRootB = body->ensureShadowRoot(ASSERT_NO_EXCEPTION);
 
     RefPtr<Element> divInY = document->createElement("div", nullAtom, ASSERT_NO_EXCEPTION);
     shadowRootY->appendChild(divInY);
-    RefPtr<ShadowRoot> shadowRootA = divInY->createShadowRoot(ASSERT_NO_EXCEPTION);
+    RefPtr<ShadowRoot> shadowRootA = divInY->ensureShadowRoot(ASSERT_NO_EXCEPTION);
 
     EXPECT_EQ(document.get(), shadowRootA->commonAncestorTreeScope(*shadowRootB));
     EXPECT_EQ(document.get(), shadowRootB->commonAncestorTreeScope(*shadowRootA));
 }
 
 TEST(TreeScopeTest, CommonAncestorOfTreesInDifferentDocuments)
 {
     RefPtr<Document> document1 = Document::create();
     RefPtr<Document> document2 = Document::create();
     EXPECT_EQ(0, document1->commonAncestorTreeScope(*document2));
     EXPECT_EQ(0, document2->commonAncestorTreeScope(*document1));
 }
 
 } // namespace