fune/layout/base/ContainStyleScopeManager.cpp
Martin Robinson f85b73bf84 Bug 1463600 - Implement CSS 'contain: style' r=emilio
Add an implementation of CSS `contain: style`. This introduces two new
data structures, the ContainStyleScope and ContainStyleScopeManager.

ContainStyleScope manages one `contain: style` "world" which has its own
counter and quote lists. The contents of these lists depend on their
parent scopes, but are not affected by their children.
ContainStyleScopeManager manages a tree of scopes starting at a root
scope which is outside of any `contain: style` element.

Scopes are stored in a hash table that is keyed off of the nsIContent
which establishes the `contain: style` scope. When modifying quote or
content lists, the ContainStyleScopeManager is responsible for finding
the appropriate `contain: style` scope to modify.

Perhaps the most complex part of this is that counters and quotes have
read access to the state of counters and quotes that are in ancestor
`contain: style` scopes. In the case of counters, USE nodes that are at
the beginning of counter lists might have a counter scope that starts in
an ancestor `contain: style` scope. When nsCounterNode::SetScope() is
called, the code may look upward in the `contain: style` scope tree to
find the start of the counter scope. In the case of quotes, the first
node in the quote list must look for the state of quotes in ancestor
`contain: style` scopes.

Differential Revision: https://phabricator.services.mozilla.com/D149508
2022-06-22 16:16:59 +00:00

242 lines
7 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/. */
#include "ContainStyleScopeManager.h"
#include "mozilla/ComputedStyle.h"
#include "mozilla/ServoStyleSet.h"
#include "CounterStyleManager.h"
#include "nsCounterManager.h"
#include "nsIContent.h"
#include "nsIContentInlines.h"
#include "nsIFrame.h"
#include "nsLayoutUtils.h"
#include "nsQuoteList.h"
namespace mozilla {
nsGenConNode* ContainStyleScope::GetPrecedingElementInGenConList(
nsGenConList* aList) {
auto IsAfter = [this](nsGenConNode* aNode) {
return nsLayoutUtils::CompareTreePosition(
mContent, aNode->mPseudoFrame->GetContent()) > 0;
};
return aList->BinarySearch(IsAfter);
}
void ContainStyleScope::RecalcAllCounters() {
GetCounterManager().RecalcAll();
for (auto* child : mChildren) {
child->RecalcAllCounters();
}
}
void ContainStyleScope::RecalcAllQuotes() {
GetQuoteList().RecalcAll();
for (auto* child : mChildren) {
child->RecalcAllQuotes();
}
}
ContainStyleScope& ContainStyleScopeManager::GetOrCreateScopeForContent(
nsIContent* aContent) {
for (; aContent; aContent = aContent->GetFlattenedTreeParent()) {
auto* element = dom::Element::FromNode(*aContent);
if (!element) {
continue;
}
// Do not allow elements which have `display: contents` to create style
// boundaries. See https://github.com/w3c/csswg-drafts/issues/7392.
if (element->IsDisplayContents()) {
continue;
}
const auto* style = Servo_Element_GetMaybeOutOfDateStyle(element);
if (!style) {
continue;
}
if (!style->SelfOrAncestorHasContainStyle()) {
return GetRootScope();
}
if (!style->StyleDisplay()->IsContainStyle()) {
continue;
}
if (auto* scope = mScopes.Get(aContent)) {
return *scope;
}
auto& parentScope =
GetOrCreateScopeForContent(aContent->GetFlattenedTreeParent());
return *mScopes.InsertOrUpdate(
aContent, MakeUnique<ContainStyleScope>(this, &parentScope, aContent));
}
return GetRootScope();
}
ContainStyleScope& ContainStyleScopeManager::GetScopeForContent(
nsIContent* aContent) {
MOZ_ASSERT(aContent);
if (auto* element = dom::Element::FromNode(*aContent)) {
if (const auto* style = Servo_Element_GetMaybeOutOfDateStyle(element)) {
if (!style->SelfOrAncestorHasContainStyle()) {
return GetRootScope();
}
}
}
for (; aContent; aContent = aContent->GetFlattenedTreeParent()) {
if (auto* scope = mScopes.Get(aContent)) {
return *scope;
}
}
return GetRootScope();
}
void ContainStyleScopeManager::Clear() {
GetRootScope().GetQuoteList().Clear();
GetRootScope().GetCounterManager().Clear();
DestroyScope(&GetRootScope());
MOZ_DIAGNOSTIC_ASSERT(mScopes.IsEmpty(),
"Destroying the root scope should destroy all scopes.");
}
void ContainStyleScopeManager::DestroyScopesFor(nsIFrame* aFrame) {
if (auto* scope = mScopes.Get(aFrame->GetContent())) {
DestroyScope(scope);
}
}
void ContainStyleScopeManager::DestroyScope(ContainStyleScope* aScope) {
// Deleting a scope modifies the array of children in its parent, so we don't
// use an iterator here.
while (!aScope->GetChildren().IsEmpty()) {
DestroyScope(aScope->GetChildren().ElementAt(0));
}
mScopes.Remove(aScope->GetContent());
}
bool ContainStyleScopeManager::DestroyCounterNodesFor(nsIFrame* aFrame) {
bool result = false;
for (auto* scope = &GetScopeForContent(aFrame->GetContent()); scope;
scope = scope->GetParent()) {
result |= scope->GetCounterManager().DestroyNodesFor(aFrame);
}
return result;
}
bool ContainStyleScopeManager::AddCounterChanges(nsIFrame* aNewFrame) {
return GetOrCreateScopeForContent(
aNewFrame->GetContent()->GetFlattenedTreeParent())
.GetCounterManager()
.AddCounterChanges(aNewFrame);
}
nsCounterList* ContainStyleScopeManager::GetOrCreateCounterList(
dom::Element& aElement, nsAtom* aCounterName) {
return GetOrCreateScopeForContent(&aElement)
.GetCounterManager()
.GetOrCreateCounterList(aCounterName);
}
bool ContainStyleScopeManager::CounterDirty(nsAtom* aCounterName) {
return mDirtyCounters.Contains(aCounterName);
}
void ContainStyleScopeManager::SetCounterDirty(nsAtom* aCounterName) {
mDirtyCounters.Insert(aCounterName);
}
void ContainStyleScopeManager::RecalcAllCounters() {
GetRootScope().RecalcAllCounters();
mDirtyCounters.Clear();
}
#if defined(DEBUG) || defined(MOZ_LAYOUT_DEBUGGER)
void ContainStyleScopeManager::DumpCounters() {
GetRootScope().GetCounterManager().Dump();
for (auto& entry : mScopes) {
entry.GetWeak()->GetCounterManager().Dump();
}
}
#endif
#ifdef ACCESSIBILITY
static bool GetFirstCounterValueForScopeAndFrame(ContainStyleScope* aScope,
nsIFrame* aFrame,
CounterValue& aOrdinal) {
if (aScope->GetCounterManager().GetFirstCounterValueForFrame(aFrame,
aOrdinal)) {
return true;
}
for (auto* child : aScope->GetChildren()) {
if (GetFirstCounterValueForScopeAndFrame(child, aFrame, aOrdinal)) {
return true;
}
}
return false;
}
void ContainStyleScopeManager::GetSpokenCounterText(nsIFrame* aFrame,
nsAString& aText) {
CounterValue ordinal = 1;
GetFirstCounterValueForScopeAndFrame(&GetRootScope(), aFrame, ordinal);
CounterStyle* counterStyle =
aFrame->PresContext()->CounterStyleManager()->ResolveCounterStyle(
aFrame->StyleList()->mCounterStyle);
nsAutoString text;
bool isBullet;
counterStyle->GetSpokenCounterText(ordinal, aFrame->GetWritingMode(), text,
isBullet);
if (isBullet) {
aText = text;
if (!counterStyle->IsNone()) {
aText.Append(' ');
}
} else {
counterStyle->GetPrefix(aText);
aText += text;
nsAutoString suffix;
counterStyle->GetSuffix(suffix);
aText += suffix;
}
}
#endif
void ContainStyleScopeManager::SetAllCountersDirty() {
GetRootScope().GetCounterManager().SetAllDirty();
for (auto& entry : mScopes) {
entry.GetWeak()->GetCounterManager().SetAllDirty();
}
}
bool ContainStyleScopeManager::DestroyQuoteNodesFor(nsIFrame* aFrame) {
bool result = false;
for (auto* scope = &GetScopeForContent(aFrame->GetContent()); scope;
scope = scope->GetParent()) {
result |= scope->GetQuoteList().DestroyNodesFor(aFrame);
}
return result;
}
nsQuoteList* ContainStyleScopeManager::QuoteListFor(dom::Element& aElement) {
return &GetOrCreateScopeForContent(&aElement).GetQuoteList();
}
void ContainStyleScopeManager::RecalcAllQuotes() {
GetRootScope().RecalcAllQuotes();
}
} // namespace mozilla