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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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 "FragmentDirective.h"
#include <cstdint>
#include "RangeBoundary.h"
#include "mozilla/Assertions.h"
#include "Document.h"
#include "mozilla/dom/FragmentDirectiveBinding.h"
#include "mozilla/dom/FragmentOrElement.h"
#include "mozilla/dom/NodeBinding.h"
#include "mozilla/dom/Text.h"
#include "mozilla/intl/WordBreaker.h"
#include "nsComputedDOMStyle.h"
#include "nsContentUtils.h"
#include "nsDOMAttributeMap.h"
#include "nsGkAtoms.h"
#include "nsICSSDeclaration.h"
#include "nsIFrame.h"
#include "nsINode.h"
#include "nsIURIMutator.h"
#include "nsRange.h"
#include "nsString.h"
namespace mozilla::dom {
static LazyLogModule sFragmentDirectiveLog("FragmentDirective");
/** Converts a `TextDirective` into a percent-encoded string. */
nsCString ToString(const TextDirective& aTextDirective) {
nsCString str;
create_text_directive(&aTextDirective, &str);
return str;
}
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(FragmentDirective, mDocument)
NS_IMPL_CYCLE_COLLECTING_ADDREF(FragmentDirective)
NS_IMPL_CYCLE_COLLECTING_RELEASE(FragmentDirective)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(FragmentDirective)
NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
FragmentDirective::FragmentDirective(Document* aDocument)
: mDocument(aDocument) {}
JSObject* FragmentDirective::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return FragmentDirective_Binding::Wrap(aCx, this, aGivenProto);
}
bool FragmentDirective::ParseAndRemoveFragmentDirectiveFromFragmentString(
nsCString& aFragment, nsTArray<TextDirective>* aTextDirectives) {
ParsedFragmentDirectiveResult fragmentDirective;
const bool hasRemovedFragmentDirective =
StaticPrefs::dom_text_fragments_enabled() &&
parse_fragment_directive(&aFragment, &fragmentDirective);
if (hasRemovedFragmentDirective) {
aFragment = fragmentDirective.url_without_fragment_directive;
if (aTextDirectives) {
aTextDirectives->SwapElements(fragmentDirective.text_directives);
}
}
return hasRemovedFragmentDirective;
}
void FragmentDirective::ParseAndRemoveFragmentDirectiveFromFragment(
nsCOMPtr<nsIURI>& aURI, nsTArray<TextDirective>* aTextDirectives) {
if (!aURI || !StaticPrefs::dom_text_fragments_enabled()) {
return;
}
bool hasRef = false;
aURI->GetHasRef(&hasRef);
if (!hasRef) {
return;
}
nsAutoCString hash;
aURI->GetRef(hash);
const bool hasRemovedFragmentDirective =
ParseAndRemoveFragmentDirectiveFromFragmentString(hash, aTextDirectives);
if (!hasRemovedFragmentDirective) {
return;
}
Unused << NS_MutateURI(aURI).SetRef(hash).Finalize(aURI);
}
nsTArray<RefPtr<nsRange>> FragmentDirective::FindTextFragmentsInDocument() {
MOZ_ASSERT(mDocument);
mDocument->FlushPendingNotifications(FlushType::Frames);
nsTArray<RefPtr<nsRange>> textDirectiveRanges;
for (const TextDirective& textDirective : mUninvokedTextDirectives) {
if (RefPtr<nsRange> range = FindRangeForTextDirective(textDirective)) {
textDirectiveRanges.AppendElement(range);
}
}
return textDirectiveRanges;
}
/**
* @brief Determine if `aNode` should be considered when traversing the DOM.
*
* A node is "search invisible" if it is an element in the HTML namespace and
* 1. The computed value of its `display` property is `none`
* 2. It serializes as void
* 3. It is one of the following types:
* - HTMLIFrameElement
* - HTMLImageElement
* - HTMLMeterElement
* - HTMLObjectElement
* - HTMLProgressElement
* - HTMLStyleElement
* - HTMLScriptElement
* - HTMLVideoElement
* - HTMLAudioElement
* 4. It is a `select` element whose `multiple` content attribute is absent
*
*/
bool NodeIsSearchInvisible(nsINode& aNode) {
if (!aNode.IsElement()) {
return false;
}
// 2. If the node serializes as void.
nsAtom* nodeNameAtom = aNode.NodeInfo()->NameAtom();
if (FragmentOrElement::IsHTMLVoid(nodeNameAtom)) {
return true;
}
// 3. Is any of the following types: HTMLIFrameElement, HTMLImageElement,
// HTMLMeterElement, HTMLObjectElement, HTMLProgressElement, HTMLStyleElement,
// HTMLScriptElement, HTMLVideoElement, HTMLAudioElement
if (aNode.IsAnyOfHTMLElements(
nsGkAtoms::iframe, nsGkAtoms::image, nsGkAtoms::meter,
nsGkAtoms::object, nsGkAtoms::progress, nsGkAtoms::style,
nsGkAtoms::script, nsGkAtoms::video, nsGkAtoms::audio)) {
return true;
}
// 4. Is a select element whose multiple content attribute is absent.
if (aNode.IsHTMLElement(nsGkAtoms::select)) {
return aNode.GetAttributes()->GetNamedItem(u"multiple"_ns) == nullptr;
}
// This is tested last because it's the most expensive check.
// 1. The computed value of its 'display' property is 'none'.
const Element* nodeAsElement = Element::FromNode(aNode);
const RefPtr<const ComputedStyle> computedStyle =
nsComputedDOMStyle::GetComputedStyleNoFlush(nodeAsElement);
return !computedStyle ||
computedStyle->StyleDisplay()->mDisplay == StyleDisplay::None;
}
/**
* @brief Returns true if `aNode` has block-level display.
* A node has block-level display if it is an element and the computed value
* of its display property is any of
* - block
* - table
* - flow-root
* - grid
* - flex
* - list-item
*
*/
bool NodeHasBlockLevelDisplay(nsINode& aNode) {
if (!aNode.IsElement()) {
return false;
}
const Element* nodeAsElement = Element::FromNode(aNode);
const RefPtr<const ComputedStyle> computedStyle =
nsComputedDOMStyle::GetComputedStyleNoFlush(nodeAsElement);
if (!computedStyle) {
return false;
}
const StyleDisplay& styleDisplay = computedStyle->StyleDisplay()->mDisplay;
return styleDisplay == StyleDisplay::Block ||
styleDisplay == StyleDisplay::Table ||
styleDisplay == StyleDisplay::FlowRoot ||
styleDisplay == StyleDisplay::Grid ||
styleDisplay == StyleDisplay::Flex || styleDisplay.IsListItem();
}
/**
* @brief Get the Block Ancestor For `aNode`.
*
*/
nsINode* GetBlockAncestorForNode(nsINode* aNode) {
// 1. Let curNode be node.
RefPtr<nsINode> curNode = aNode;
// 2. While curNode is non-null
while (curNode) {
// 2.1. If curNode is not a Text node and it has block-level display then
// return curNode.
if (!curNode->IsText() && NodeHasBlockLevelDisplay(*curNode)) {
return curNode;
}
// 2.2. Otherwise, set curNode to curNode’s parent.
curNode = curNode->GetParentNode();
}
// 3.Return node’s node document's document element.
return aNode->GetOwnerDocument();
}
/**
* @brief Returns true if `aNode` is part of a non-searchable subtree.
*
* A node is part of a non-searchable subtree if it is or has a shadow-including
* ancestor that is search invisible.
*
*/
bool NodeIsPartOfNonSearchableSubTree(nsINode& aNode) {
nsINode* node = &aNode;
do {
if (NodeIsSearchInvisible(*node)) {
return true;
}
} while ((node = node->GetParentOrShadowHostNode()));
return false;
}
/**
* @brief Return true if `aNode` is a visible Text node.
*
* A node is a visible text node if it is a Text node, the computed value of
* its parent element's visibility property is visible, and it is being
* rendered.
*
*/
bool NodeIsVisibleTextNode(const nsINode& aNode) {
const Text* text = Text::FromNode(aNode);
if (!text) {
return false;
}
const nsIFrame* frame = text->GetPrimaryFrame();
return frame && frame->StyleVisibility()->IsVisible();
}
enum class TextScanDirection { Left = -1, Right = 1 };
/**
* @brief Tests if there is whitespace at the given position and direction.
*
* This algorithm tests for whitespaces and `&nbsp;` at `aPos`.
* It returns the size of the whitespace found at the position, i.e. 5/6 for
* `&nbsp/;` and 1 otherwise.
*
* This function follows a subsection of this section of the spec, but has been
* adapted to be able to scan in both directions:
*/
uint32_t IsWhitespaceAtPosition(nsString& aText, uint32_t aPos,
TextScanDirection aDirection) {
if (aText.Length() == 0) {
return 0;
}
if (aDirection == TextScanDirection::Right) {
if (aText.Length() > (aPos + 5)) {
if (Substring(aText, aPos, 5).Equals(u"&nbsp")) {
return aText.Length() > (aPos + 6) && aText.CharAt(aPos + 6) == u';'
? 6
: 5;
}
}
} else {
if (aPos > 6 && Substring(aText, aPos - 6, 6).Equals(u"&nbsp;")) {
return 6;
}
if (aPos > 5 && Substring(aText, aPos - 5, 5).Equals(u"&nbsp")) {
return 5;
}
}
return uint32_t(IsSpaceCharacter(aText.CharAt(aPos)));
}
/** Advances the start of `aRange` to the next non-whitespace position.
* The function follows this section of the spec:
*/
void AdvanceStartToNextNonWhitespacePosition(nsRange& aRange) {
// 1. While range is not collapsed:
while (!aRange.Collapsed()) {
// 1.1. Let node be range's start node.
RefPtr<nsINode> node = aRange.GetStartContainer();
MOZ_ASSERT(node);
// 1.2. Let offset be range's start offset.
const uint32_t offset = aRange.StartOffset();
// 1.3. If node is part of a non-searchable subtree or if node is not a
// visible text node or if offset is equal to node's length then:
if (NodeIsPartOfNonSearchableSubTree(*node) ||
!NodeIsVisibleTextNode(*node) || offset == node->Length()) {
// 1.3.1. Set range's start node to the next node, in shadow-including
// tree order.
// 1.3.2. Set range's start offset to 0.
if (NS_FAILED(aRange.SetStart(node->GetNextNode(), 0))) {
return;
}
// 1.3.3. Continue.
continue;
}
const Text* text = Text::FromNode(node);
nsAutoString textData;
text->GetData(textData);
// These steps are moved to `IsWhitespaceAtPosition()`.
// 1.4. If the substring data of node at offset offset and count 6 is equal
// to the string "&nbsp;" then:
// 1.4.1. Add 6 to range’s start offset.
// 1.5. Otherwise, if the substring data of node at offset offset and count
// 5 is equal to the string "&nbsp" then:
// 1.5.1. Add 5 to range’s start offset.
// 1.6. Otherwise:
// 1.6.1 Let cp be the code point at the offset index in node’s data.
// 1.6.2 If cp does not have the White_Space property set, return.
// 1.6.3 Add 1 to range’s start offset.
const uint32_t whitespace =
IsWhitespaceAtPosition(textData, offset, TextScanDirection::Right);
if (whitespace == 0) {
return;
}
aRange.SetStart(node, offset + whitespace);
}
}
/**
* @brief Moves `aRangeBoundary` one word in `aDirection`.
*
* Word boundaries are determined using `intl::WordBreaker::FindWord()`.
*
*
* @param aRangeBoundary[in] The range boundary that should be moved.
* Must be set and valid.
* @param aDirection[in] The direction into which to move.
* @return A new `RangeBoundary` which is moved to the next word.
*/
RangeBoundary MoveRangeBoundaryOneWord(const RangeBoundary& aRangeBoundary,
TextScanDirection aDirection) {
MOZ_ASSERT(aRangeBoundary.IsSetAndValid());
RefPtr<nsINode> curNode = aRangeBoundary.Container();
uint32_t offset = *aRangeBoundary.Offset(
RangeBoundary::OffsetFilter::kValidOrInvalidOffsets);
const int offsetIncrement = int(aDirection);
// Get the text node of the start of the range and the offset.
// This is the current position of the start of the range.
nsAutoString text;
if (NodeIsVisibleTextNode(*curNode)) {
const Text* textNode = Text::FromNode(curNode);
textNode->GetData(text);
// Assuming that the current position might not be at a word boundary,
// advance to the word boundary at word begin/end.
if (!IsWhitespaceAtPosition(text, offset, aDirection)) {
const intl::WordRange wordRange =
intl::WordBreaker::FindWord(text, offset);
if (aDirection == TextScanDirection::Right &&
offset != wordRange.mBegin) {
offset = wordRange.mEnd;
} else if (aDirection == TextScanDirection::Left &&
offset != wordRange.mEnd) {
// The additional -1 is necessary to move to offset to *before* the
// start of the word.
offset = wordRange.mBegin - 1;
}
}
}
// Now, skip any whitespace, so that `offset` points to the word boundary of
// the next word (which is the one this algorithm actually aims to move over).
while (curNode) {
if (!NodeIsVisibleTextNode(*curNode) || NodeIsSearchInvisible(*curNode) ||
offset >= curNode->Length()) {
curNode = aDirection == TextScanDirection::Left ? curNode->GetPrevNode()
: curNode->GetNextNode();
if (!curNode) {
break;
}
offset =
aDirection == TextScanDirection::Left ? curNode->Length() - 1 : 0;
if (const Text* textNode = Text::FromNode(curNode)) {
textNode->GetData(text);
}
continue;
}
if (const uint32_t whitespace =
IsWhitespaceAtPosition(text, offset, aDirection)) {
offset += offsetIncrement * whitespace;
continue;
}
// At this point, the caret has been moved to the next non-whitespace
// position.
// find word boundaries at the current position
const intl::WordRange wordRange = intl::WordBreaker::FindWord(text, offset);
offset = aDirection == TextScanDirection::Left ? wordRange.mBegin
: wordRange.mEnd;
return {curNode, offset};
}
return {};
}
RefPtr<nsRange> FragmentDirective::FindRangeForTextDirective(
const TextDirective& aTextDirective) {
MOZ_LOG(sFragmentDirectiveLog, LogLevel::Info,
("FragmentDirective::%s(): Find range for text directive '%s'.",
__FUNCTION__, ToString(aTextDirective).Data()));
// 1. Let searchRange be a range with start (document, 0) and end (document,
// document’s length)
ErrorResult rv;
RefPtr<nsRange> searchRange =
nsRange::Create(mDocument, 0, mDocument, mDocument->Length(), rv);
if (rv.Failed()) {
return nullptr;
}
// 2. While searchRange is not collapsed:
while (!searchRange->Collapsed()) {
// 2.1. Let potentialMatch be null.
RefPtr<nsRange> potentialMatch;
// 2.2. If parsedValues’s prefix is not null:
if (!aTextDirective.prefix.IsEmpty()) {
// 2.2.1. Let prefixMatch be the the result of running the find a string
// in range steps with query parsedValues’s prefix, searchRange
// searchRange, wordStartBounded true and wordEndBounded false.
RefPtr<nsRange> prefixMatch =
FindStringInRange(searchRange, aTextDirective.prefix, true, false);
// 2.2.2. If prefixMatch is null, return null.
if (!prefixMatch) {
return nullptr;
}
// 2.2.3. Set searchRange’s start to the first boundary point after
// prefixMatch’s start
const RangeBoundary boundaryPoint = MoveRangeBoundaryOneWord(
{prefixMatch->GetStartContainer(), prefixMatch->StartOffset()},
TextScanDirection::Right);
if (!boundaryPoint.IsSetAndValid()) {
return nullptr;
}
searchRange->SetStart(boundaryPoint.AsRaw(), rv);
if (rv.Failed()) {
return nullptr;
}
// 2.2.4. Let matchRange be a range whose start is prefixMatch’s end and
// end is searchRange’s end.
RefPtr<nsRange> matchRange = nsRange::Create(
prefixMatch->GetEndContainer(), prefixMatch->EndOffset(),
searchRange->GetEndContainer(), searchRange->EndOffset(), rv);
if (rv.Failed()) {
return nullptr;
}
// 2.2.5. Advance matchRange’s start to the next non-whitespace position.
AdvanceStartToNextNonWhitespacePosition(*matchRange);
// 2.2.6. If matchRange is collapsed return null.
// (This can happen if prefixMatch’s end or its subsequent non-whitespace
// position is at the end of the document.)
if (matchRange->Collapsed()) {
return nullptr;
}
// 2.2.7. Assert: matchRange’s start node is a Text node.
// (matchRange’s start now points to the next non-whitespace text data
// following a matched prefix.)
MOZ_ASSERT(matchRange->GetStartContainer()->IsText());
// 2.2.8. Let mustEndAtWordBoundary be true if parsedValues’s end is
// non-null or parsedValues’s suffix is null, false otherwise.
const bool mustEndAtWordBoundary =
!aTextDirective.end.IsEmpty() || aTextDirective.suffix.IsEmpty();
// 2.2.9. Set potentialMatch to the result of running the find a string in
// range steps with query parsedValues’s start, searchRange matchRange,
// wordStartBounded false, and wordEndBounded mustEndAtWordBoundary.
potentialMatch = FindStringInRange(matchRange, aTextDirective.start,
false, mustEndAtWordBoundary);
// 2.2.10. If potentialMatch is null, return null.
if (!potentialMatch) {
return nullptr;
}
// 2.2.11. If potentialMatch’s start is not matchRange’s start, then
// continue.
// (In this case, we found a prefix but it was followed by something other
// than a matching text so we’ll continue searching for the next instance
// of prefix.)
if (potentialMatch->GetStartContainer() !=
matchRange->GetStartContainer()) {
continue;
}
}
// 2.3. Otherwise:
else {
// 2.3.1. Let mustEndAtWordBoundary be true if parsedValues’s end is
// non-null or parsedValues’s suffix is null, false otherwise.
const bool mustEndAtWordBoundary =
!aTextDirective.end.IsEmpty() || aTextDirective.suffix.IsEmpty();
// 2.3.2. Set potentialMatch to the result of running the find a string in
// range steps with query parsedValues’s start, searchRange searchRange,
// wordStartBounded true, and wordEndBounded mustEndAtWordBoundary.
potentialMatch = FindStringInRange(searchRange, aTextDirective.start,
true, mustEndAtWordBoundary);
// 2.3.3. If potentialMatch is null, return null.
if (!potentialMatch) {
return nullptr;
}
// 2.3.4. Set searchRange’s start to the first boundary point after
// potentialMatch’s start
RangeBoundary newRangeBoundary = MoveRangeBoundaryOneWord(
{potentialMatch->GetStartContainer(), potentialMatch->StartOffset()},
TextScanDirection::Right);
if (!newRangeBoundary.IsSetAndValid()) {
return nullptr;
}
searchRange->SetStart(newRangeBoundary.AsRaw(), rv);
if (rv.Failed()) {
return nullptr;
}
}
// 2.4. Let rangeEndSearchRange be a range whose start is potentialMatch’s
// end and whose end is searchRange’s end.
RefPtr<nsRange> rangeEndSearchRange = nsRange::Create(
potentialMatch->GetEndContainer(), potentialMatch->EndOffset(),
searchRange->GetEndContainer(), searchRange->EndOffset(), rv);
if (rv.Failed()) {
return nullptr;
}
// 2.5. While rangeEndSearchRange is not collapsed:
while (!rangeEndSearchRange->Collapsed()) {
// 2.5.1. If parsedValues’s end item is non-null, then:
if (!aTextDirective.end.IsEmpty()) {
// 2.5.1.1. Let mustEndAtWordBoundary be true if parsedValues’s suffix
// is null, false otherwise.
const bool mustEndAtWordBoundary = aTextDirective.suffix.IsEmpty();
// 2.5.1.2. Let endMatch be the result of running the find a string in
// range steps with query parsedValues’s end, searchRange
// rangeEndSearchRange, wordStartBounded true, and wordEndBounded
// mustEndAtWordBoundary.
RefPtr<nsRange> endMatch =
FindStringInRange(rangeEndSearchRange, aTextDirective.end, true,
mustEndAtWordBoundary);
// 2.5.1.3. If endMatch is null then return null.
if (!endMatch) {
return nullptr;
}
// 2.5.1.4. Set potentialMatch’s end to endMatch’s end.
potentialMatch->SetEnd(endMatch->GetEndContainer(),
endMatch->EndOffset());
}
// 2.5.2. Assert: potentialMatch is non-null, not collapsed and represents
// a range exactly containing an instance of matching text.
MOZ_ASSERT(potentialMatch && !potentialMatch->Collapsed());
// 2.5.3. If parsedValues’s suffix is null, return potentialMatch.
if (aTextDirective.suffix.IsEmpty()) {
return potentialMatch;
}
// 2.5.4. Let suffixRange be a range with start equal to potentialMatch’s
// end and end equal to searchRange’s end.
RefPtr<nsRange> suffixRange = nsRange::Create(
potentialMatch->GetEndContainer(), potentialMatch->EndOffset(),
searchRange->GetEndContainer(), searchRange->EndOffset(), rv);
if (rv.Failed()) {
return nullptr;
}
// 2.5.5. Advance suffixRange's start to the next non-whitespace position.
AdvanceStartToNextNonWhitespacePosition(*suffixRange);
// 2.5.6. Let suffixMatch be result of running the find a string in range
// steps with query parsedValue's suffix, searchRange suffixRange,
// wordStartBounded false, and wordEndBounded true.
RefPtr<nsRange> suffixMatch =
FindStringInRange(suffixRange, aTextDirective.suffix, false, true);
// 2.5.7. If suffixMatch is null, return null.
// (If the suffix doesn't appear in the remaining text of the document,
// there's no possible way to make a match.)
if (!suffixMatch) {
return nullptr;
}
// 2.5.8. If suffixMatch's start is suffixRange's start, return
// potentialMatch.
if (suffixMatch->GetStartContainer() ==
suffixRange->GetStartContainer() &&
suffixMatch->StartOffset() == suffixRange->StartOffset()) {
return potentialMatch;
}
// 2.5.9. If parsedValue's end item is null then break;
// (If this is an exact match and the suffix doesn’t match, start
// searching for the next range start by breaking out of this loop without
// rangeEndSearchRange being collapsed. If we’re looking for a range
// match, we’ll continue iterating this inner loop since the range start
// will already be correct.)
if (aTextDirective.end.IsEmpty()) {
break;
}
// 2.5.10. Set rangeEndSearchRange's start to potentialMatch's end.
// (Otherwise, it is possible that we found the correct range start, but
// not the correct range end. Continue the inner loop to keep searching
// for another matching instance of rangeEnd.)
rangeEndSearchRange->SetStart(potentialMatch->GetEndContainer(),
potentialMatch->EndOffset());
}
// 2.6. If rangeEndSearchRange is collapsed then:
if (rangeEndSearchRange->Collapsed()) {
// 2.6.1. Assert parsedValue's end item is non-null.
// (This can only happen for range matches due to the break for exact
// matches in step 9 of the above loop. If we couldn’t find a valid
// rangeEnd+suffix pair anywhere in the doc then there’s no possible way
// to make a match.)
// XXX(:jjaschke): should this really assert?
MOZ_ASSERT(!aTextDirective.end.IsEmpty());
}
}
// 3. Return null.
return nullptr;
}
/**
* @brief Convenience function that returns true if the given position in a
* string is a word boundary.
*
* This is a thin wrapper around the `WordBreaker::FindWord()` function.
*
* @param aText The text input.
* @param aPosition The position to check.
* @return true if there is a word boundary at `aPosition`.
* @return false otherwise.
*/
bool IsAtWordBoundary(const nsAString& aText, uint32_t aPosition) {
const intl::WordRange wordRange =
intl::WordBreaker::FindWord(aText, aPosition);
return wordRange.mBegin == aPosition || wordRange.mEnd == aPosition;
}
enum class IsEndIndex : bool { No, Yes };
RangeBoundary GetBoundaryPointAtIndex(
uint32_t aIndex, const nsTArray<RefPtr<Text>>& aTextNodeList,
IsEndIndex aIsEndIndex) {
// 1. Let counted be 0.
uint32_t counted = 0;
// 2. For each curNode of nodes:
for (Text* curNode : aTextNodeList) {
// 2.1. Let nodeEnd be counted + curNode’s length.
uint32_t nodeEnd = counted + curNode->Length();
// 2.2. If isEnd is true, add 1 to nodeEnd.
if (aIsEndIndex == IsEndIndex::Yes) {
++nodeEnd;
}
// 2.3. If nodeEnd is greater than index then:
if (nodeEnd > aIndex) {
// 2.3.1. Return the boundary point (curNode, index − counted).
return RangeBoundary(curNode->AsNode(), aIndex - counted);
}
// 2.4. Increment counted by curNode’s length.
counted += curNode->Length();
}
return {};
}
RefPtr<nsRange> FindRangeFromNodeList(
nsRange* aSearchRange, const nsAString& aQuery,
const nsTArray<RefPtr<Text>>& aTextNodeList, bool aWordStartBounded,
bool aWordEndBounded) {
// 1. Let searchBuffer be the concatenation of the data of each item in nodes.
// XXX(:jjaschke): There's an open issue here that deals with what
// data is supposed to be (text data vs. rendered text)
uint32_t bufferLength = 0;
for (const Text* text : aTextNodeList) {
bufferLength += text->Length();
}
// bail out if the search query is longer than the text data.
if (bufferLength < aQuery.Length()) {
return nullptr;
}
nsAutoString searchBuffer;
searchBuffer.SetCapacity(bufferLength);
for (Text* text : aTextNodeList) {
text->AppendTextTo(searchBuffer);
}
// 2. Let searchStart be 0.
// 3. If the first item in nodes is searchRange’s start node then set
// searchStart to searchRange’s start offset.
uint32_t searchStart =
aTextNodeList.SafeElementAt(0) == aSearchRange->GetStartContainer()
? aSearchRange->StartOffset()
: 0;
// 4. Let start and end be boundary points, initially null.
RangeBoundary start, end;
// 5. Let matchIndex be null.
// "null" here doesn't mean 0, instead "not set". 0 would be a valid index.
// Therefore, "null" is represented by the value -1.
int32_t matchIndex = -1;
// 6. While matchIndex is null
// As explained above, "null" == -1 in this algorithm.
while (matchIndex == -1) {
// 6.1. Set matchIndex to the index of the first instance of queryString in
// searchBuffer, starting at searchStart. The string search must be
// performed using a base character comparison, or the primary level, as
// defined in [UTS10].
// [UTS10]
// Ken Whistler; Markus Scherer.Unicode Collation Algorithm.26 August 2022.
// Unicode Technical Standard #10.
// XXX(:jjaschke): For the initial implementation, a standard case-sensitive
// find-in-string is used.
matchIndex = searchBuffer.Find(aQuery, searchStart);
// 6.2. If matchIndex is null, return null.
if (matchIndex == -1) {
return nullptr;
}
// 6.3. Let endIx be matchIndex + queryString’s length.
// endIx is the index of the last character in the match + 1.
const uint32_t endIx = matchIndex + aQuery.Length();
// 6.4. Set start to the boundary point result of get boundary point at
// index matchIndex run over nodes with isEnd false.
start = GetBoundaryPointAtIndex(matchIndex, aTextNodeList, IsEndIndex::No);
// 6.5. Set end to the boundary point result of get boundary point at index
// endIx run over nodes with isEnd true.
end = GetBoundaryPointAtIndex(endIx, aTextNodeList, IsEndIndex::Yes);
// 6.6. If wordStartBounded is true and matchIndex is not at a word boundary
// in searchBuffer, given the language from start’s node as the locale; or
// wordEndBounded is true and matchIndex + queryString’s length is not at a
// word boundary in searchBuffer, given the language from end’s node as the
// locale:
if ((aWordStartBounded && !IsAtWordBoundary(searchBuffer, matchIndex)) ||
(aWordEndBounded && !IsAtWordBoundary(searchBuffer, endIx))) {
// 6.6.1. Set searchStart to matchIndex + 1.
searchStart = matchIndex + 1;
// 6.6.2. Set matchIndex to null.
matchIndex = -1;
}
}
// 7. Let endInset be 0.
// 8. If the last item in nodes is searchRange’s end node then set endInset
// to (searchRange’s end node's length − searchRange’s end offset)
// (endInset is the offset from the last position in the last node in the
// reverse direction. Alternatively, it is the length of the node that’s not
// included in the range.)
uint32_t endInset =
aTextNodeList.LastElement() == aSearchRange->GetEndContainer()
? aSearchRange->GetEndContainer()->Length() -
aSearchRange->EndOffset()
: 0;
// 9. If matchIndex + queryString’s length is greater than searchBuffer’s
// length − endInset return null.
// (If the match runs past the end of the search range, return null.)
if (matchIndex + aQuery.Length() > searchBuffer.Length() - endInset) {
return nullptr;
}
// 10. Assert: start and end are non-null, valid boundary points in
// searchRange.
MOZ_ASSERT(start.IsSetAndValid());
MOZ_ASSERT(end.IsSetAndValid());
// 11. Return a range with start start and end end.
ErrorResult rv;
RefPtr<nsRange> range = nsRange::Create(start, end, rv);
if (rv.Failed()) {
return nullptr;
}
return range;
}
RefPtr<nsRange> FragmentDirective::FindStringInRange(nsRange* aSearchRange,
const nsAString& aQuery,
bool aWordStartBounded,
bool aWordEndBounded) {
MOZ_ASSERT(aSearchRange);
RefPtr<nsRange> searchRange = aSearchRange->CloneRange();
// 1. While searchRange is not collapsed
while (searchRange && !searchRange->Collapsed()) {
// 1.1. Let curNode be searchRange’s start node.
RefPtr<nsINode> curNode = searchRange->GetStartContainer();
// 1.2. If curNode is part of a non-searchable subtree:
if (NodeIsPartOfNonSearchableSubTree(*curNode)) {
// 1.2.1. Set searchRange’s start node to the next node, in
// shadow-including tree order, that isn’t a shadow-including descendant
// of curNode.
RefPtr<nsINode> next = curNode;
while ((next = next->GetNextNode())) {
if (!next->IsShadowIncludingInclusiveDescendantOf(curNode)) {
break;
}
}
if (!next) {
return nullptr;
}
// 1.2.2. Set `searchRange`s `start offset` to 0
searchRange->SetStart(next, 0);
// 1.2.3. continue.
continue;
}
// 1.3. If curNode is not a visible TextNode:
if (!NodeIsVisibleTextNode(*curNode)) {
// 1.3.1. Set searchRange’s start node to the next node, in
// shadow-including tree order, that is not a doctype.
RefPtr<nsINode> next = curNode;
while ((next = next->GetNextNode())) {
if (next->NodeType() != Node_Binding::DOCUMENT_TYPE_NODE) {
break;
}
}
if (!next) {
return nullptr;
}
// 1.3.2. Set searchRange’s start offset to 0.
searchRange->SetStart(next, 0);
// 1.3.3. continue.
continue;
}
// 1.4. Let blockAncestor be the nearest block ancestor of `curNode`
RefPtr<nsINode> blockAncestor = GetBlockAncestorForNode(curNode);
// 1.5. Let textNodeList be a list of Text nodes, initially empty.
nsTArray<RefPtr<Text>> textNodeList;
// 1.6. While curNode is a shadow-including descendant of blockAncestor and
// the position of the boundary point (curNode,0) is not after searchRange's
// end:
while (curNode &&
curNode->IsShadowIncludingInclusiveDescendantOf(blockAncestor)) {
Maybe<int32_t> comp = nsContentUtils::ComparePoints(
curNode, 0, searchRange->GetEndContainer(), searchRange->EndOffset());
if (comp) {
if (*comp >= 0) {
break;
}
} else {
// This means that the compared nodes are disconnected.
return nullptr;
}
// 1.6.1. If curNode has block-level display, then break.
if (NodeHasBlockLevelDisplay(*curNode)) {
break;
}
// 1.6.2. If curNode is search invisible:
if (NodeIsSearchInvisible(*curNode)) {
// 1.6.2.1. Set curNode to the next node, in shadow-including tree
// order, that isn't a shadow-including descendant of curNode.
curNode = curNode->GetNextNode();
// 1.6.2.2. Continue.
continue;
}
// 1.6.3. If curNode is a visible text node then append it to
// textNodeList.
if (NodeIsVisibleTextNode(*curNode)) {
textNodeList.AppendElement(curNode->AsText());
}
// 1.6.4. Set curNode to the next node in shadow-including
// tree order.
curNode = curNode->GetNextNode();
}
// 1.7. Run the find a range from a node list steps given
// query, searchRange, textNodeList, wordStartBounded, wordEndBounded as
// input. If the resulting Range is not null, then return it.
if (RefPtr<nsRange> range =
FindRangeFromNodeList(searchRange, aQuery, textNodeList,
aWordStartBounded, aWordEndBounded)) {
return range;
}
// 1.8. If curNode is null, then break.
if (!curNode) {
break;
}
// 1.9. Assert: curNode follows searchRange's start node.
// 1.10. Set searchRange's start to the boundary point (curNode,0).
searchRange->SetStart(curNode, 0);
}
// 2. Return null.
return nullptr;
}
} // namespace mozilla::dom