gecko-dev/dom/html/HTMLContentElement.h
Kirk Steuber 7fdb378650 Bug 1359556 - Optimize cloneNode by preinitializing attribute and child arrays r=bz
Currently, attribute and child arrays (implemented in dom/base/nsAttrAndChildArray.h) start out empty. When cloning, the array ends up being resized multiple times in order to add the attributes and children that are being cloned from the original node. This would be quicker if the array was initialized to the correct size in the first place so that resizes are not necessary.

However, preallocating space for children is only necessary when performing a deep clone. Therefore, an additional parameter is being added to the Clone, CopyInnerTo, and CloneDocHelper methods to indicate whether preallocation of children should happen. Attributes are copied either way, so that part of the array is preallocated in both cases.

MozReview-Commit-ID: 3iVezeAKXnI

--HG--
extra : rebase_source : 9c3deec6d7aafd6411044d623d4863637b45fd58
2017-04-20 12:57:48 -07:00

137 lines
4.2 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_HTMLContentElement_h__
#define mozilla_dom_HTMLContentElement_h__
#include "nsAutoPtr.h"
#include "nsINodeList.h"
#include "nsGenericHTMLElement.h"
struct nsCSSSelectorList;
namespace mozilla {
namespace dom {
class DistributedContentList;
class HTMLContentElement final : public nsGenericHTMLElement
{
public:
explicit HTMLContentElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo);
// nsISupports
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(HTMLContentElement,
nsGenericHTMLElement)
static HTMLContentElement* FromContent(nsIContent* aContent)
{
if (aContent->IsHTMLContentElement()) {
return static_cast<HTMLContentElement*>(aContent);
}
return nullptr;
}
virtual bool IsHTMLContentElement() const override { return true; }
virtual nsresult Clone(mozilla::dom::NodeInfo *aNodeInfo, nsINode **aResult,
bool aPreallocateChildren) const override;
virtual nsIDOMNode* AsDOMNode() override { return this; }
virtual nsresult BindToTree(nsIDocument* aDocument, nsIContent* aParent,
nsIContent* aBindingParent,
bool aCompileEventHandlers) override;
virtual void UnbindFromTree(bool aDeep = true,
bool aNullParent = true) override;
/**
* Returns whether if the selector of this insertion point
* matches the provided content.
*/
bool Match(nsIContent* aContent);
bool IsInsertionPoint() const { return mIsInsertionPoint; }
nsCOMArray<nsIContent>& MatchedNodes() { return mMatchedNodes; }
void AppendMatchedNode(nsIContent* aContent);
void RemoveMatchedNode(nsIContent* aContent);
void InsertMatchedNode(uint32_t aIndex, nsIContent* aContent);
void ClearMatchedNodes();
virtual nsresult SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
nsIAtom* aPrefix, const nsAString& aValue,
bool aNotify) override;
virtual nsresult UnsetAttr(int32_t aNameSpaceID, nsIAtom* aAttribute,
bool aNotify) override;
// WebIDL methods.
already_AddRefed<DistributedContentList> GetDistributedNodes();
void GetSelect(nsAString& aSelect)
{
Element::GetAttr(kNameSpaceID_None, nsGkAtoms::select, aSelect);
}
void SetSelect(const nsAString& aSelect)
{
Element::SetAttr(kNameSpaceID_None, nsGkAtoms::select, aSelect, true);
}
protected:
virtual ~HTMLContentElement();
virtual JSObject* WrapNode(JSContext *aCx, JS::Handle<JSObject*> aGivenProto) override;
/**
* Updates the destination insertion points of the fallback
* content of this insertion point. If there are nodes matched
* to this insertion point, then destination insertion points
* of fallback are cleared, otherwise, this insertion point
* is a destination insertion point.
*/
void UpdateFallbackDistribution();
/**
* An array of nodes from the ShadowRoot host that match the
* content insertion selector.
*/
nsCOMArray<nsIContent> mMatchedNodes;
nsAutoPtr<nsCSSSelectorList> mSelectorList;
bool mValidSelector;
bool mIsInsertionPoint;
};
class DistributedContentList : public nsINodeList
{
public:
explicit DistributedContentList(HTMLContentElement* aHostElement);
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(DistributedContentList)
// nsIDOMNodeList
NS_DECL_NSIDOMNODELIST
// nsINodeList
virtual nsIContent* Item(uint32_t aIndex) override;
virtual int32_t IndexOf(nsIContent* aContent) override;
virtual nsINode* GetParentObject() override { return mParent; }
virtual JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;
protected:
virtual ~DistributedContentList();
RefPtr<HTMLContentElement> mParent;
nsCOMArray<nsIContent> mDistributedNodes;
};
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_HTMLContentElement_h__