gecko-dev/dom/base/BindContext.h

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/* -*- 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/. */
/* State that is passed down to BindToTree. */
#ifndef mozilla_dom_BindContext_h__
#define mozilla_dom_BindContext_h__
#include "mozilla/Attributes.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/ShadowRoot.h"
#include "nsINode.h"
namespace mozilla {
namespace dom {
class Document;
struct MOZ_STACK_CLASS BindContext final {
// The document that owns the tree we're getting bound to.
//
// This is mostly an optimization to avoid silly pointer-chases to get the
// OwnerDoc().
Document& OwnerDoc() const { return mDoc; }
// Whether we're getting connected.
//
// https://dom.spec.whatwg.org/#connected
bool InComposedDoc() const { return mInComposedDoc; }
// Whether we're getting bound to the document tree.
//
// https://dom.spec.whatwg.org/#in-a-document-tree
bool InUncomposedDoc() const { return mInUncomposedDoc; }
Document* GetComposedDoc() const { return mInComposedDoc ? &mDoc : nullptr; }
Document* GetUncomposedDoc() const {
return mInUncomposedDoc ? &mDoc : nullptr;
}
// Whether our subtree root is changing as a result of this operation.
bool SubtreeRootChanges() const { return mSubtreeRootChanges; }
// Autofocus is allowed only if the is in the same origin as the top level
// document.
// https://html.spec.whatwg.org/multipage/interaction.html#the-autofocus-attribute:same-origin
// In addition, the document should not be already loaded and the
// "browser.autofocus" preference should be 'true'.
bool AllowsAutoFocus() const;
// This constructor should be used for regular appends to content.
explicit BindContext(nsINode& aParent)
: mDoc(*aParent.OwnerDoc()),
mInComposedDoc(aParent.IsInComposedDoc()),
mInUncomposedDoc(aParent.IsInUncomposedDoc()),
mSubtreeRootChanges(true) {}
// When re-binding a shadow host into a tree, we re-bind all the shadow tree
// from the root. In that case, the shadow tree contents remain within the
// same subtree root. So children should avoid doing silly things like adding
// themselves to the ShadowRoot's id table twice or what not.
//
// This constructor is only meant to be used in that situation.
explicit BindContext(ShadowRoot& aShadowRoot)
: mDoc(*aShadowRoot.OwnerDoc()),
mInComposedDoc(aShadowRoot.IsInComposedDoc()),
mInUncomposedDoc(false),
mSubtreeRootChanges(false) {}
// This constructor is meant to be used when inserting native-anonymous
// children into a subtree.
enum ForNativeAnonymous { ForNativeAnonymous };
BindContext(Element& aParentElement, enum ForNativeAnonymous)
: mDoc(*aParentElement.OwnerDoc()),
mInComposedDoc(aParentElement.IsInComposedDoc()),
mInUncomposedDoc(aParentElement.IsInUncomposedDoc()),
mSubtreeRootChanges(true) {
MOZ_ASSERT(mInComposedDoc, "Binding NAC in a disconnected subtree?");
}
private:
// Returns true iff the document is in the same origin as the top level
// document.
bool IsSameOriginAsTop() const;
Document& mDoc;
const bool mInComposedDoc;
const bool mInUncomposedDoc;
// Whether the bind operation will change the subtree root of the content
// we're binding.
const bool mSubtreeRootChanges;
};
} // namespace dom
} // namespace mozilla
#endif