mediawiki-extensions-Discus.../includes/CommentModifier.php
Bartosz Dziewoński af68c835bb Update exception handling for new code conventions
Change code to match the documented consensus formed on T321683:
https://www.mediawiki.org/wiki/Manual:Coding_conventions/PHP#Exception_handling

* Do not directly throw Exception, Error or MWException
* Document checked exceptions with @throws
* Do not document unchecked exceptions

For this extension, I think it makes sense to consider DOMException an
unchecked exception too (in addition to the usual LogicException and
RuntimeException).

Depends-On: Id07e301c3f20afa135e5469ee234a27354485652
Depends-On: I869af06896b9757af18488b916211c5a41a8c563
Depends-On: I42d9b7465d1406a22ef1b3f6d8de426c60c90e2c
Change-Id: Ic9d9efd031a87fa5a93143f714f0adb20f0dd956
2023-01-22 18:17:11 +00:00

700 lines
24 KiB
PHP

<?php
namespace MediaWiki\Extension\DiscussionTools;
use InvalidArgumentException;
use LogicException;
use MediaWiki\Extension\DiscussionTools\ThreadItem\ContentCommentItem;
use MediaWiki\Extension\DiscussionTools\ThreadItem\ContentThreadItem;
use MediaWiki\MediaWikiServices;
use UnexpectedValueException;
use Wikimedia\Assert\Assert;
use Wikimedia\Parsoid\DOM\Document;
use Wikimedia\Parsoid\DOM\DocumentFragment;
use Wikimedia\Parsoid\DOM\Element;
use Wikimedia\Parsoid\DOM\Node;
use Wikimedia\Parsoid\DOM\Text;
use Wikimedia\Parsoid\Utils\DOMCompat;
use Wikimedia\Parsoid\Utils\DOMUtils;
class CommentModifier {
private function __construct() {
}
/**
* Add an attribute to a list item to remove pre-whitespace in Parsoid
*
* @param Element $listItem
*/
private static function whitespaceParsoidHack( Element $listItem ): void {
// HACK: Setting data-parsoid removes the whitespace after the list item,
// which makes nested lists work.
// This is undocumented behaviour and probably very fragile.
$listItem->setAttribute( 'data-parsoid', '{}' );
}
/**
* Remove extra linebreaks from a wikitext string
*
* @param string $wikitext
* @return string
*/
public static function sanitizeWikitextLinebreaks( string $wikitext ): string {
$wikitext = CommentUtils::htmlTrim( $wikitext );
$wikitext = preg_replace( "/\r/", "\n", $wikitext );
$wikitext = preg_replace( "/\n+/", "\n", $wikitext );
return $wikitext;
}
/**
* Given a comment and a reply link, add the reply link to its document's DOM tree, at the end of
* the comment.
*
* @param ContentCommentItem $comment
* @param Node $linkNode Reply link
*/
public static function addReplyLink( ContentCommentItem $comment, Node $linkNode ): void {
$target = $comment->getRange()->endContainer;
// Insert the link before trailing whitespace.
// In the MediaWiki parser output, <ul>/<dl> nodes are preceded by a newline. Normally it isn't
// visible on the page. But if we insert an inline element (the reply link) after it, it becomes
// meaningful and gets rendered, which results in additional spacing before some reply links.
// Split the text node, so that we can insert the link before the trailing whitespace.
if ( $target instanceof Text ) {
preg_match( '/\s*$/', $target->nodeValue ?? '', $matches, PREG_OFFSET_CAPTURE );
$byteOffset = $matches[0][1];
$charOffset = mb_strlen(
substr( $target->nodeValue ?? '', 0, $byteOffset )
);
$target->splitText( $charOffset );
}
$target->parentNode->insertBefore( $linkNode, $target->nextSibling );
}
/**
* Given a comment, add a list item to its document's DOM tree, inside of which a reply to said
* comment can be added.
*
* The DOM tree is suitably rearranged to ensure correct indentation level of the reply (wrapper
* nodes are added, and other nodes may be moved around).
*
* @param ContentThreadItem $comment
* @param string $replyIndentation Reply indentation syntax to use, one of:
* - 'invisible' (use `<dl><dd>` tags to output `:` in wikitext)
* - 'bullet' (use `<ul><li>` tags to output `*` in wikitext)
* @return Element
*/
public static function addListItem( ContentThreadItem $comment, string $replyIndentation ): Element {
$listTypeMap = [
'li' => 'ul',
'dd' => 'dl'
];
// 1. Start at given comment
// 2. Skip past all comments with level greater than the given
// (or in other words, all replies, and replies to replies, and so on)
// 3. Add comment with level of the given comment plus 1
$curComment = $comment;
while ( count( $curComment->getReplies() ) ) {
$replies = $curComment->getReplies();
$curComment = end( $replies );
}
// Tag names for lists and items we're going to insert
if ( $replyIndentation === 'invisible' ) {
$itemType = 'dd';
} elseif ( $replyIndentation === 'bullet' ) {
$itemType = 'li';
} else {
throw new InvalidArgumentException( "Invalid reply indentation syntax '$replyIndentation'" );
}
$listType = $listTypeMap[ $itemType ];
$desiredLevel = $comment->getLevel() + 1;
$target = $curComment->getRange()->endContainer;
// target is a text node or an inline element at the end of a "paragraph"
// (not necessarily paragraph node).
// First, we need to find a block-level parent that we can mess with.
// If we can't find a surrounding list item or paragraph (e.g. maybe we're inside a table cell
// or something), take the parent node and hope for the best.
$parent = CommentUtils::closestElement( $target, [ 'li', 'dd', 'p' ] ) ??
$target->parentNode;
while ( $target->parentNode !== $parent ) {
$target = $target->parentNode;
}
// parent is a list item or paragraph (hopefully)
// target is an inline node within it
// If the comment is fully covered by some wrapper element, insert replies outside that wrapper.
// This will often just be a paragraph node (<p>), but it can be a <div> or <table> that serves
// as some kind of a fancy frame, which are often used for barnstars and announcements.
// @phan-suppress-next-line PhanTypeMismatchArgumentNullable
$excludedWrapper = CommentUtils::closestElement( $target, [ 'section' ] ) ?:
$curComment->getRootNode();
$covered = CommentUtils::getFullyCoveredSiblings( $curComment, $excludedWrapper );
if ( $curComment->getLevel() === 1 && $covered ) {
$target = end( $covered );
$parent = $target->parentNode;
}
// If the comment is in a transclusion, insert replies after the transclusion. (T313100)
// This method should never be called in cases where that would be a bad idea.
// @phan-suppress-next-line PhanTypeMismatchArgumentNullable
$transclusionNode = CommentUtils::getTranscludedFromElement( $target );
if ( $transclusionNode ) {
while (
( $nextSibling = $transclusionNode->nextSibling ) &&
$nextSibling instanceof Element &&
$nextSibling->getAttribute( 'about' ) === $transclusionNode->getAttribute( 'about' )
) {
$transclusionNode = $nextSibling;
}
$target = $transclusionNode;
$parent = $target->parentNode;
}
// If we can't insert a list directly inside this element, insert after it.
// The covered wrapper check above handles most cases, but we still need this sometimes, such as:
// * If the comment starts in the middle of a list, then ends with an unindented p/pre, the
// wrapper check doesn't adjust the parent
// * If the comment consists of multiple list items (starting with a <dt>, so that the comment is
// considered to be unindented, that is level === 1), but not all of them, the wrapper check
// adjusts the parent to be the list, and the rest of the algorithm doesn't handle that well
if (
strtolower( $parent->tagName ) === 'p' ||
strtolower( $parent->tagName ) === 'pre' ||
strtolower( $parent->tagName ) === 'ul' ||
strtolower( $parent->tagName ) === 'dl'
) {
$parent = $parent->parentNode;
$target = $target->parentNode;
}
Assert::precondition( $target !== null, 'We have not stepped outside the document' );
// Instead of just using $curComment->getLevel(), consider indentation of lists within the
// comment (T252702)
$curLevel = CommentUtils::getIndentLevel( $target, $curComment->getRootNode() ) + 1;
$item = null;
if ( $desiredLevel === 1 ) {
// Special handling for top-level comments
// We use section=new API for adding them in PHP, so this should never happen
throw new UnexpectedValueException( "Can't add a top-level comment" );
} elseif ( $curLevel < $desiredLevel ) {
// Insert more lists after the target to increase nesting.
// Parsoid puts HTML comments (and other "rendering-transparent nodes", e.g. category links)
// which appear at the end of the line in wikitext outside the paragraph,
// but we usually shouldn't insert replies between the paragraph and such comments. (T257651)
// Skip over comments and whitespace, but only update target when skipping past comments.
$pointer = $target;
while (
$pointer->nextSibling && (
CommentUtils::isRenderingTransparentNode( $pointer->nextSibling ) ||
(
$pointer->nextSibling instanceof Text &&
CommentUtils::htmlTrim( $pointer->nextSibling->nodeValue ?? '' ) === '' &&
// If more that two lines of whitespace are detected, the following HTML
// comments are not considered to be part of the reply (T264026)
!preg_match( '/(\r?\n){2,}/', $pointer->nextSibling->nodeValue ?? '' )
)
)
) {
$pointer = $pointer->nextSibling;
if ( CommentUtils::isRenderingTransparentNode( $pointer ) ) {
$target = $pointer;
}
}
// Insert required number of wrappers
while ( $curLevel < $desiredLevel ) {
$list = $target->ownerDocument->createElement( $listType );
// Setting modified would only be needed for removeAddedListItem,
// which isn't needed on the server
// $list->setAttribute( 'dt-modified', 'new' );
$item = $target->ownerDocument->createElement( $itemType );
// $item->setAttribute( 'dt-modified', 'new' );
$parent->insertBefore( $list, $target->nextSibling );
$list->appendChild( $item );
$target = $item;
$parent = $list;
$curLevel++;
}
} else {
// Split the ancestor nodes after the target to decrease nesting.
do {
if ( !$target || !$parent ) {
throw new LogicException( 'Can not decrease nesting any more' );
}
// If target is the last child of its parent, no need to split it
if ( $target->nextSibling ) {
// Create new identical node after the parent
$newNode = $parent->cloneNode( false );
// $parent->setAttribute( 'dt-modified', 'split' );
$parent->parentNode->insertBefore( $newNode, $parent->nextSibling );
// Move nodes following target to the new node
while ( $target->nextSibling ) {
$newNode->appendChild( $target->nextSibling );
}
}
$target = $parent;
$parent = $parent->parentNode;
// Decrease nesting level if we escaped outside of a list
if ( isset( $listTypeMap[ strtolower( $target->tagName ) ] ) ) {
$curLevel--;
}
} while ( $curLevel >= $desiredLevel );
// parent is now a list, target is a list item
if ( $itemType === strtolower( $target->tagName ) ) {
$item = $target->ownerDocument->createElement( $itemType );
// $item->setAttribute( 'dt-modified', 'new' );
$parent->insertBefore( $item, $target->nextSibling );
} else {
// This is the wrong type of list, split it one more time
// If target is the last child of its parent, no need to split it
if ( $target->nextSibling ) {
// Create new identical node after the parent
$newNode = $parent->cloneNode( false );
// $parent->setAttribute( 'dt-modified', 'split' );
$parent->parentNode->insertBefore( $newNode, $parent->nextSibling );
// Move nodes following target to the new node
while ( $target->nextSibling ) {
$newNode->appendChild( $target->nextSibling );
}
}
$target = $parent;
$parent = $parent->parentNode;
// Insert a list of the right type in the middle
$list = $target->ownerDocument->createElement( $listType );
// Setting modified would only be needed for removeAddedListItem,
// which isn't needed on the server
// $list->setAttribute( 'dt-modified', 'new' );
$item = $target->ownerDocument->createElement( $itemType );
// $item->setAttribute( 'dt-modified', 'new' );
$parent->insertBefore( $list, $target->nextSibling );
$list->appendChild( $item );
}
}
if ( $item === null ) {
throw new LogicException( 'No item found' );
}
return $item;
}
/**
* Check all elements in a node list are of a given type
*
* Also returns false if there are no elements in the list
*
* @param iterable<Node> $nodes Node list
* @param string $type Element type
* @return bool
*/
private static function allOfType( iterable $nodes, string $type ): bool {
$hasElements = false;
foreach ( $nodes as $node ) {
if ( $node instanceof Element ) {
if ( strtolower( $node->tagName ) !== strtolower( $type ) ) {
return false;
}
$hasElements = true;
}
}
return $hasElements;
}
/**
* Remove unnecessary list wrappers from a comment fragment
*
* TODO: Implement this in JS if required
*
* @param DocumentFragment $fragment Fragment
*/
public static function unwrapFragment( DocumentFragment $fragment ): void {
// Wrap orphaned list items
$list = null;
if ( static::allOfType( $fragment->childNodes, 'dd' ) ) {
$list = $fragment->ownerDocument->createElement( 'dl' );
} elseif ( static::allOfType( $fragment->childNodes, 'li' ) ) {
$list = $fragment->ownerDocument->createElement( 'ul' );
}
if ( $list ) {
while ( $fragment->firstChild ) {
$list->appendChild( $fragment->firstChild );
}
$fragment->appendChild( $list );
}
// If all child nodes are lists of the same type, unwrap them
while (
static::allOfType( $fragment->childNodes, 'dl' ) ||
static::allOfType( $fragment->childNodes, 'ul' ) ||
static::allOfType( $fragment->childNodes, 'ol' )
) {
// Do not iterate over childNodes while we're modifying it
$childNodeList = iterator_to_array( $fragment->childNodes );
foreach ( $childNodeList as $node ) {
static::unwrapList( $node, $fragment );
}
}
}
// removeAddedListItem is only needed in the client
/**
* Unwrap a top level list, converting list item text to paragraphs
*
* Assumes that the list has a parent node, or is a root child in the provided
* document fragment.
*
* @param Node $list DOM node, will be wrapped if it is a list element (dl/ol/ul)
* @param DocumentFragment|null $fragment Containing document fragment if list has no parent
*/
public static function unwrapList( Node $list, ?DocumentFragment $fragment = null ): void {
$doc = $list->ownerDocument;
$container = $fragment ?: $list->parentNode;
$referenceNode = $list;
if ( !(
$list instanceof Element && (
strtolower( $list->tagName ) === 'dl' ||
strtolower( $list->tagName ) === 'ol' ||
strtolower( $list->tagName ) === 'ul'
)
) ) {
// Not a list, leave alone (e.g. auto-generated ref block)
return;
}
// If the whole list is a template return it unmodified (T253150)
if ( CommentUtils::getTranscludedFromElement( $list ) ) {
return;
}
while ( $list->firstChild ) {
if ( $list->firstChild instanceof Element ) {
// Move <dd> contents to <p>
$p = $doc->createElement( 'p' );
while ( $list->firstChild->firstChild ) {
// If contents is a block element, place outside the paragraph
// and start a new paragraph after
if ( CommentUtils::isBlockElement( $list->firstChild->firstChild ) ) {
if ( $p->firstChild ) {
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $p;
$container->insertBefore( $p, $insertBefore );
}
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $list->firstChild->firstChild;
$container->insertBefore( $list->firstChild->firstChild, $insertBefore );
$p = $doc->createElement( 'p' );
} else {
$p->appendChild( $list->firstChild->firstChild );
}
}
if ( $p->firstChild ) {
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $p;
$container->insertBefore( $p, $insertBefore );
}
$list->removeChild( $list->firstChild );
} else {
// Text node / comment node, probably empty
$insertBefore = $referenceNode->nextSibling;
$referenceNode = $list->firstChild;
$container->insertBefore( $list->firstChild, $insertBefore );
}
}
$container->removeChild( $list );
}
/**
* Add another list item after the given one.
*
* @param Element $previousItem
* @return Element
*/
public static function addSiblingListItem( Element $previousItem ): Element {
$listItem = $previousItem->ownerDocument->createElement( $previousItem->tagName );
$previousItem->parentNode->insertBefore( $listItem, $previousItem->nextSibling );
return $listItem;
}
/**
* Create an element that will convert to the provided wikitext
*
* @param Document $doc
* @param string $wikitext
* @return Element
*/
public static function createWikitextNode( Document $doc, string $wikitext ): Element {
$span = $doc->createElement( 'span' );
$span->setAttribute( 'typeof', 'mw:Transclusion' );
$span->setAttribute( 'data-mw', json_encode( [ 'parts' => [ $wikitext ] ] ) );
return $span;
}
/**
* Check if an element created by ::createWikitextNode() starts with list item markup.
*
* @param Element $node
* @return bool
*/
private static function isWikitextNodeListItem( Element $node ): bool {
$dataMw = json_decode( $node->getAttribute( 'data-mw' ) ?? '', true );
$wikitextLine = $dataMw['parts'][0] ?? null;
return $wikitextLine && is_string( $wikitextLine ) &&
in_array( $wikitextLine[0], [ '*', '#', ':', ';' ] );
}
/**
* Append a user signature to the comment in the container.
*
* @param DocumentFragment $container
* @param string $signature
*/
public static function appendSignature( DocumentFragment $container, string $signature ): void {
$doc = $container->ownerDocument;
// If the last node isn't a paragraph (e.g. it's a list created in visual mode),
// or looks like a list item created in wikitext mode (T263217),
// then add another paragraph to contain the signature.
$wrapperNode = $container->lastChild;
if (
!( $wrapperNode instanceof Element ) ||
strtolower( $wrapperNode->tagName ) !== 'p' ||
(
// This would be easier to check in prepareWikitextReply(), but that would result
// in an empty list item being added at the end if we don't need to add a signature.
( $wtNode = $wrapperNode->lastChild ) &&
$wtNode instanceof Element &&
static::isWikitextNodeListItem( $wtNode )
)
) {
$container->appendChild( $doc->createElement( 'p' ) );
}
// If the last node is empty, trim the signature to prevent leading whitespace triggering
// preformatted text (T269188, T276612)
if ( !$container->lastChild->firstChild ) {
$signature = ltrim( $signature, ' ' );
}
// Sign the last line
$container->lastChild->appendChild(
static::createWikitextNode(
$doc,
$signature
)
);
}
/**
* Append a user signature to the comment in the provided wikitext.
*
* @param string $wikitext
* @param string $signature
* @return string
*/
public static function appendSignatureWikitext( string $wikitext, string $signature ): string {
$wikitext = CommentUtils::htmlTrim( $wikitext );
$lines = explode( "\n", $wikitext );
$lastLine = end( $lines );
// If last line looks like a list item, add an empty line afterwards for the signature (T263217)
if ( $lastLine && in_array( $lastLine[0], [ '*', '#', ':', ';' ] ) ) {
$wikitext .= "\n";
// Trim the signature to prevent leading whitespace triggering preformatted text (T269188, T276612)
$signature = ltrim( $signature, ' ' );
}
return $wikitext . $signature;
}
/**
* Add a reply to a specific comment
*
* @param ContentThreadItem $comment Comment being replied to
* @param DocumentFragment $container Container of comment DOM nodes
*/
public static function addReply( ContentThreadItem $comment, DocumentFragment $container ): void {
$services = MediaWikiServices::getInstance();
$dtConfig = $services->getConfigFactory()->makeConfig( 'discussiontools' );
$replyIndentation = $dtConfig->get( 'DiscussionToolsReplyIndentation' );
$newParsoidItem = null;
// Transfer comment DOM to Parsoid DOM
// Wrap every root node of the document in a new list item (dd/li).
// In wikitext mode every root node is a paragraph.
// In visual mode the editor takes care of preventing problematic nodes
// like <table> or <h2> from ever occurring in the comment.
while ( $container->childNodes->length ) {
if ( !$newParsoidItem ) {
$newParsoidItem = static::addListItem( $comment, $replyIndentation );
} else {
$newParsoidItem = static::addSiblingListItem( $newParsoidItem );
}
// Suppress space after the indentation character to support nested lists (T238218).
// By request from the community, avoid this if possible after bullet indentation (T259864).
if ( !(
$replyIndentation === 'bullet' &&
( $wtNode = $container->firstChild->lastChild ) &&
$wtNode instanceof Element &&
!static::isWikitextNodeListItem( $wtNode )
) ) {
static::whitespaceParsoidHack( $newParsoidItem );
}
$newParsoidItem->appendChild( $container->firstChild );
}
}
/**
* Transfer comment DOM nodes into a list node, as if adding a reply, but without requiring a
* ThreadItem.
*
* @param DocumentFragment $container Container of comment DOM nodes
* @return Element $node List node
*/
public static function transferReply( DocumentFragment $container ): Element {
$services = MediaWikiServices::getInstance();
$dtConfig = $services->getConfigFactory()->makeConfig( 'discussiontools' );
$replyIndentation = $dtConfig->get( 'DiscussionToolsReplyIndentation' );
$doc = $container->ownerDocument;
// Like addReply(), but we make our own list
$list = $doc->createElement( $replyIndentation === 'invisible' ? 'dl' : 'ul' );
while ( $container->childNodes->length ) {
$item = $doc->createElement( $replyIndentation === 'invisible' ? 'dd' : 'li' );
// Suppress space after the indentation character to support nested lists (T238218).
// By request from the community, avoid this if possible after bullet indentation (T259864).
if ( !(
$replyIndentation === 'bullet' &&
( $wtNode = $container->firstChild->lastChild ) &&
$wtNode instanceof Element &&
!static::isWikitextNodeListItem( $wtNode )
) ) {
static::whitespaceParsoidHack( $item );
}
$item->appendChild( $container->firstChild );
$list->appendChild( $item );
}
return $list;
}
/**
* Create a container of comment DOM nodes from wikitext
*
* @param Document $doc Document where the DOM nodes will be inserted
* @param string $wikitext
* @return DocumentFragment DOM nodes
*/
public static function prepareWikitextReply( Document $doc, string $wikitext ): DocumentFragment {
$container = $doc->createDocumentFragment();
$wikitext = static::sanitizeWikitextLinebreaks( $wikitext );
$lines = explode( "\n", $wikitext );
foreach ( $lines as $line ) {
$p = $doc->createElement( 'p' );
$p->appendChild( static::createWikitextNode( $doc, $line ) );
$container->appendChild( $p );
}
return $container;
}
/**
* Create a container of comment DOM nodes from HTML
*
* @param Document $doc Document where the DOM nodes will be inserted
* @param string $html
* @return DocumentFragment DOM nodes
*/
public static function prepareHtmlReply( Document $doc, string $html ): DocumentFragment {
$container = DOMUtils::parseHTMLToFragment( $doc, $html );
// Remove empty lines
// This should really be anything that serializes to empty string in wikitext,
// (e.g. <h2></h2>) but this will catch most cases
// Create a non-live child node list, so we don't have to worry about it changing
// as nodes are removed.
$childNodeList = iterator_to_array( $container->childNodes );
foreach ( $childNodeList as $node ) {
if ( (
$node instanceof Text &&
CommentUtils::htmlTrim( $node->nodeValue ?? '' ) === ''
) || (
$node instanceof Element &&
strtolower( $node->tagName ) === 'p' &&
CommentUtils::htmlTrim( DOMCompat::getInnerHTML( $node ) ) === ''
) ) {
$container->removeChild( $node );
}
}
return $container;
}
/**
* Add a reply in the DOM to a comment using wikitext.
*
* @param ContentCommentItem $comment Comment being replied to
* @param string $wikitext
* @param string|null $signature
*/
public static function addWikitextReply(
ContentCommentItem $comment, string $wikitext, string $signature = null
): void {
$doc = $comment->getRange()->endContainer->ownerDocument;
$container = static::prepareWikitextReply( $doc, $wikitext );
if ( $signature !== null ) {
static::appendSignature( $container, $signature );
}
static::addReply( $comment, $container );
}
/**
* Add a reply in the DOM to a comment using HTML.
*
* @param ContentCommentItem $comment Comment being replied to
* @param string $html
* @param string|null $signature
*/
public static function addHtmlReply(
ContentCommentItem $comment, string $html, string $signature = null
): void {
$doc = $comment->getRange()->endContainer->ownerDocument;
$container = static::prepareHtmlReply( $doc, $html );
if ( $signature !== null ) {
static::appendSignature( $container, $signature );
}
static::addReply( $comment, $container );
}
}