gecko-dev/layout/base/nsStyleChangeList.cpp

82 строки
3.4 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/. */
/*
* a list of the recomputation that needs to be done in response to a
* style change
*/
#include "nsStyleChangeList.h"
#include "nsCSSFrameConstructor.h"
#include "nsIContent.h"
#include "nsIFrame.h"
void
nsStyleChangeList::AppendChange(nsIFrame* aFrame, nsIContent* aContent, nsChangeHint aHint)
{
MOZ_ASSERT(aFrame || (aHint & nsChangeHint_ReconstructFrame),
"must have frame");
MOZ_ASSERT(aHint, "No hint to process?");
MOZ_ASSERT(!(aHint & nsChangeHint_NeutralChange),
"Neutral changes do not need extra processing, "
"and should be stripped out");
MOZ_ASSERT(aContent || !(aHint & nsChangeHint_ReconstructFrame),
"must have content");
// XXXbz we should make this take Element instead of nsIContent
MOZ_ASSERT(!aContent || aContent->IsElement() ||
// display:contents elements posts the changes for their children:
(aFrame && aContent->GetParent() &&
aFrame->PresContext()->FrameConstructor()->
GetDisplayContentsStyleFor(aContent->GetParent())) ||
(aContent->IsNodeOfType(nsINode::eTEXT) &&
aContent->IsStyledByServo() &&
aContent->HasFlag(NODE_NEEDS_FRAME) &&
aHint & nsChangeHint_ReconstructFrame),
"Shouldn't be trying to restyle non-elements directly, "
"except if it's a display:contents child or a text node "
"doing lazy frame construction");
MOZ_ASSERT(!(aHint & nsChangeHint_AllReflowHints) ||
(aHint & nsChangeHint_NeedReflow),
"Reflow hint bits set without actually asking for a reflow");
if (aHint & nsChangeHint_ReconstructFrame) {
// If Servo fires reconstruct at a node, it is the only change hint fired at
// that node.
if (IsServo()) {
// Note: Because we check whether |aHint| is a reconstruct above (which is
// necessary to avoid debug test timeouts on certain crashtests), this check
// will not find bugs where we add a non-reconstruct hint for an element after
// adding a reconstruct. This is ok though, since ProcessRestyledFrames will
// handle that case via mDestroyedFrames.
#ifdef DEBUG
for (size_t i = 0; i < Length(); ++i) {
MOZ_ASSERT(aContent != (*this)[i].mContent ||
!((*this)[i].mHint & nsChangeHint_ReconstructFrame),
"Should not append a non-ReconstructFrame hint after \
appending a ReconstructFrame hint for the same \
content.");
}
#endif
} else {
// Filter out all other changes for same content for Gecko (Servo asserts against this
// case above).
// NOTE: This is captured by reference to please static analysis.
// Capturing it by value as a pointer should be fine in this case.
RemoveElementsBy([&](const nsStyleChangeData& aData) {
return aData.mContent == aContent;
});
}
}
if (!IsEmpty() && aFrame && aFrame == LastElement().mFrame) {
LastElement().mHint |= aHint;
return;
}
AppendElement(nsStyleChangeData { aFrame, aContent, aHint });
}