gecko-dev/layout/base/nsQuoteList.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

166 lines
5.2 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/. */
/* implementation of quotes for the CSS 'content' property */
#include "nsQuoteList.h"
#include "nsReadableUtils.h"
#include "nsIContent.h"
#include "nsIFrame.h"
#include "nsIFrameInlines.h"
#include "nsContainerFrame.h"
#include "mozilla/ContainStyleScopeManager.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/dom/Text.h"
#include "mozilla/intl/Quotes.h"
using namespace mozilla;
bool nsQuoteNode::InitTextFrame(nsGenConList* aList, nsIFrame* aPseudoFrame,
nsIFrame* aTextFrame) {
nsGenConNode::InitTextFrame(aList, aPseudoFrame, aTextFrame);
nsQuoteList* quoteList = static_cast<nsQuoteList*>(aList);
bool dirty = false;
quoteList->Insert(this);
if (quoteList->IsLast(this))
quoteList->Calc(this);
else
dirty = true;
// Don't set up text for 'no-open-quote' and 'no-close-quote'.
if (IsRealQuote()) {
aTextFrame->GetContent()->AsText()->SetText(Text(), false);
}
return dirty;
}
nsString nsQuoteNode::Text() {
NS_ASSERTION(mType == StyleContentType::OpenQuote ||
mType == StyleContentType::CloseQuote,
"should only be called when mText should be non-null");
nsString result;
int32_t depth = Depth();
MOZ_ASSERT(depth >= -1);
if (depth < 0) {
return result;
}
const auto& quotesProp = mPseudoFrame->StyleList()->mQuotes;
if (quotesProp.IsAuto()) {
// Look up CLDR-derived quotation marks for the language of the context.
const nsIFrame* frame = mPseudoFrame->GetInFlowParent();
// Parent of the pseudo is the element around which the quotes are applied;
// we want lang from *its* parent, unless it is the root.
// XXX Are there other cases where we shouldn't look up to the parent?
if (!frame->Style()->IsRootElementStyle()) {
if (const nsIFrame* parent = frame->GetInFlowParent()) {
frame = parent;
}
}
const intl::Quotes* quotes =
intl::QuotesForLang(frame->StyleFont()->mLanguage);
// If we don't have quote-mark data for the language, use built-in
// defaults.
if (!quotes) {
static const intl::Quotes sDefaultQuotes = {
{0x201c, 0x201d, 0x2018, 0x2019}};
quotes = &sDefaultQuotes;
}
size_t index = (depth == 0 ? 0 : 2); // select first or second pair
index += (mType == StyleContentType::OpenQuote ? 0 : 1); // open or close
result.Append(quotes->mChars[index]);
return result;
}
MOZ_ASSERT(quotesProp.IsQuoteList());
const Span<const StyleQuotePair> quotes = quotesProp.AsQuoteList().AsSpan();
// Reuse the last pair when the depth is greater than the number of
// pairs of quotes. (Also make 'quotes: none' and close-quote from
// a depth of 0 equivalent for the next test.)
if (depth >= static_cast<int32_t>(quotes.Length())) {
depth = static_cast<int32_t>(quotes.Length()) - 1;
}
if (depth == -1) {
// close-quote from a depth of 0 or 'quotes: none'
return result;
}
const StyleQuotePair& pair = quotes[depth];
const StyleOwnedStr& quote =
mType == StyleContentType::OpenQuote ? pair.opening : pair.closing;
result.Assign(NS_ConvertUTF8toUTF16(quote.AsString()));
return result;
}
static int32_t GetDepthBeforeFirstQuoteNode(ContainStyleScope* aScope) {
for (auto* ancestor = aScope->GetParent(); ancestor;
ancestor = ancestor->GetParent()) {
auto& quoteList = ancestor->GetQuoteList();
if (auto* node = static_cast<nsQuoteNode*>(
aScope->GetPrecedingElementInGenConList(&quoteList))) {
return node->DepthAfter();
}
}
return 0;
}
void nsQuoteList::Calc(nsQuoteNode* aNode) {
if (aNode == FirstNode()) {
aNode->mDepthBefore = GetDepthBeforeFirstQuoteNode(mScope);
} else {
aNode->mDepthBefore = Prev(aNode)->DepthAfter();
}
}
void nsQuoteList::RecalcAll() {
for (nsQuoteNode* node = FirstNode(); node; node = Next(node)) {
int32_t oldDepth = node->mDepthBefore;
Calc(node);
if (node->mDepthBefore != oldDepth && node->mText && node->IsRealQuote())
node->mText->SetData(node->Text(), IgnoreErrors());
}
}
#ifdef DEBUG
void nsQuoteList::PrintChain() {
using StyleContentType = nsQuoteNode::StyleContentType;
printf("Chain: \n");
for (nsQuoteNode* node = FirstNode(); node; node = Next(node)) {
printf(" %p %d - ", static_cast<void*>(node), node->mDepthBefore);
switch (node->mType) {
case StyleContentType::OpenQuote:
printf("open");
break;
case StyleContentType::NoOpenQuote:
printf("noOpen");
break;
case StyleContentType::CloseQuote:
printf("close");
break;
case StyleContentType::NoCloseQuote:
printf("noClose");
break;
default:
printf("unknown!!!");
}
printf(" %d - %d,", node->Depth(), node->DepthAfter());
if (node->mText) {
nsAutoString data;
node->mText->GetData(data);
printf(" \"%s\",", NS_ConvertUTF16toUTF8(data).get());
}
printf("\n");
}
}
#endif