DerivedPageDataUpdater.php
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DerivedPageDataUpdater.php
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	<?php
	/**
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, write to the Free Software Foundation, Inc.,
	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	* http://www.gnu.org/copyleft/gpl.html
	*
	* @file
	*/

	namespace MediaWiki\Storage;

	use InvalidArgumentException;
	use LogicException;
	use MediaWiki\ChangeTags\ChangeTags;
	use MediaWiki\ChangeTags\ChangeTagsStore;
	use MediaWiki\Config\ServiceOptions;
	use MediaWiki\Content\Content;
	use MediaWiki\Content\IContentHandlerFactory;
	use MediaWiki\Content\Transform\ContentTransformer;
	use MediaWiki\Deferred\DeferrableUpdate;
	use MediaWiki\Deferred\DeferredUpdates;
	use MediaWiki\Deferred\LinksUpdate\LinksUpdate;
	use MediaWiki\Deferred\RefreshSecondaryDataUpdate;
	use MediaWiki\Deferred\SiteStatsUpdate;
	use MediaWiki\DomainEvent\DomainEventDispatcher;
	use MediaWiki\Edit\PreparedEdit;
	use MediaWiki\HookContainer\HookContainer;
	use MediaWiki\HookContainer\HookRunner;
	use MediaWiki\JobQueue\JobQueueGroup;
	use MediaWiki\JobQueue\Jobs\ParsoidCachePrewarmJob;
	use MediaWiki\Language\Language;
	use MediaWiki\Logging\LogPage;
	use MediaWiki\MainConfigNames;
	use MediaWiki\Page\Event\PageRevisionUpdatedEvent;
	use MediaWiki\Page\PageIdentity;
	use MediaWiki\Page\ParserOutputAccess;
	use MediaWiki\Page\ProperPageIdentity;
	use MediaWiki\Page\WikiPage;
	use MediaWiki\Page\WikiPageFactory;
	use MediaWiki\Parser\ParserCache;
	use MediaWiki\Parser\ParserOptions;
	use MediaWiki\Parser\ParserOutput;
	use MediaWiki\Revision\MutableRevisionRecord;
	use MediaWiki\Revision\RenderedRevision;
	use MediaWiki\Revision\RevisionRecord;
	use MediaWiki\Revision\RevisionRenderer;
	use MediaWiki\Revision\RevisionSlots;
	use MediaWiki\Revision\RevisionStore;
	use MediaWiki\Revision\SlotRecord;
	use MediaWiki\Revision\SlotRoleRegistry;
	use MediaWiki\Title\Title;
	use MediaWiki\User\UserIdentity;
	use MediaWiki\Utils\MWTimestamp;
	use Psr\Log\LoggerAwareInterface;
	use Psr\Log\LoggerInterface;
	use Psr\Log\NullLogger;
	use Wikimedia\Assert\Assert;
	use Wikimedia\ObjectCache\WANObjectCache;
	use Wikimedia\Rdbms\IDBAccessObject;
	use Wikimedia\Rdbms\ILBFactory;

	/**
	* A handle for managing updates for derived page data on edit, import, purge, etc.
	*
	* @note Avoid direct usage of DerivedPageDataUpdater.
	*
	* @todo Define interfaces for the different use cases of DerivedPageDataUpdater, particularly
	* providing access to post-PST content and ParserOutput to callbacks during revision creation,
	* which currently use WikiPage::prepareContentForEdit, and allowing updates to be triggered on
	* purge, import, and undeletion, which currently use WikiPage::doEditUpdates() and
	* Content::getSecondaryDataUpdates().
	*
	* DerivedPageDataUpdater instances are designed to be cached inside a WikiPage instance,
	* and re-used by callback code over the course of an update operation. It's a stepping stone
	* on the way to a more complete refactoring of WikiPage.
	*
	* When using a DerivedPageDataUpdater, the following life cycle must be observed:
	* grabCurrentRevision (optional), prepareContent (optional), prepareUpdate (required
	* for doUpdates). getCanonicalParserOutput, getSlots, and getSecondaryDataUpdates
	* require prepareContent or prepareUpdate to have been called first, to initialize the
	* DerivedPageDataUpdater.
	*
	* MCR migration note: this replaces the relevant methods in WikiPage, and covers the use cases
	* of PreparedEdit.
	*
	* @see docs/pageupdater.md for more information.
	*
	* @internal
	* @since 1.32
	* @ingroup Page
	*/
	class DerivedPageDataUpdater implements LoggerAwareInterface, PreparedUpdate {

	/**
	* @var UserIdentity\|null
	*/
	private $user = null;

	/**
	* @var WikiPage
	*/
	private $wikiPage;

	/**
	* @var ParserCache
	*/
	private $parserCache;

	/**
	* @var RevisionStore
	*/
	private $revisionStore;

	/**
	* @var Language
	*/
	private $contLang;

	/**
	* @var JobQueueGroup
	*/
	private $jobQueueGroup;

	/**
	* @var ILBFactory
	*/
	private $loadbalancerFactory;

	/**
	* @var HookRunner
	*/
	private $hookRunner;

	/**
	* @var DomainEventDispatcher
	*/
	private $eventDispatcher;

	/**
	* @var LoggerInterface
	*/
	private $logger;

	/**
	* @var string see $wgArticleCountMethod
	*/
	private $articleCountMethod;

	/**
	* Stores (most of) the $options parameter of prepareUpdate().
	* @see prepareUpdate()
	*
	* @var array
	* @phpcs:ignore Generic.Files.LineLength
	* @phan-var array{changed:bool,created:bool,moved:bool,cause:string,oldrevision:null\|RevisionRecord,triggeringUser:null\|UserIdentity,oldredirect:bool\|null\|string,oldcountable:bool\|null\|string,causeAction:null\|string,causeAgent:null\|string,editResult:null\|EditResult}
	*/
	private $options = [
	'changed' => true,
	// newrev is true if prepareUpdate is handling the creation of a new revision,
	// as opposed to a null edit or a forced update.
	'newrev' => false,
	'created' => false,
	'oldtitle' => null,
	'oldrevision' => null,
	'oldcountable' => null,
	'oldredirect' => null,
	'triggeringUser' => null,
	// causeAction/causeAgent default to 'unknown' but that's handled where it's read,
	// to make the life of prepareUpdate() callers easier.
	'causeAction' => null,
	'causeAgent' => null,
	'editResult' => null,
	'rcPatrolStatus' => 0,
	'tags' => [],
	'cause' => 'edit',
	'emitEvents' => true,
	] + PageRevisionUpdatedEvent::DEFAULT_FLAGS;

	/**
	* The state of the relevant row in page table before the edit.
	* This is determined by the first call to grabCurrentRevision, prepareContent,
	* or prepareUpdate (so it is only accessible in 'knows-current' or a later stage).
	* If pageState was not initialized when prepareUpdate() is called, prepareUpdate() will
	* attempt to emulate the state of the page table before the edit.
	*
	* Contains the following fields:
	* - oldRevision (RevisionRecord\|null): the revision that was current before the change
	* associated with this update. Might not be set, use getParentRevision().
	* - oldId (int\|null): the id of the above revision. 0 if there is no such revision (the change
	* was about creating a new page); null if not known (that should not happen).
	* - oldIsRedirect (bool\|null): whether the page was a redirect before the change. Lazy-loaded,
	* can be null; use wasRedirect() instead of direct access.
	* - oldCountable (bool\|null): whether the page was countable before the change (or null
	* if we don't have that information)
	* - oldRecord (ExistingPageRecord\|null): the page record before the update (or null
	* if the page didn't exist)
	*
	* @var array
	*/
	private $pageState = null;

	/**
	* @var RevisionSlotsUpdate\|null
	*/
	private $slotsUpdate = null;

	/**
	* @var RevisionRecord\|null
	*/
	private $parentRevision = null;

	/**
	* @var RevisionRecord\|null
	*/
	private $revision = null;

	/**
	* @var RenderedRevision
	*/
	private $renderedRevision = null;

	/** @var ?PageRevisionUpdatedEvent */
	private $pageRevisionUpdatedEvent = null;

	/**
	* @var RevisionRenderer
	*/
	private $revisionRenderer;

	/** @var SlotRoleRegistry */
	private $slotRoleRegistry;

	/**
	* @var bool Whether null-edits create a revision.
	*/
	private $forceEmptyRevision = false;

	/**
	* A stage identifier for managing the life cycle of this instance.
	* Possible stages are 'new', 'knows-current', 'has-content', 'has-revision', and 'done'.
	*
	* @see docs/pageupdater.md for documentation of the life cycle.
	*
	* @var string
	*/
	private $stage = 'new';

	/**
	* Transition table for managing the life cycle of DerivedPageDateUpdater instances.
	*
	* XXX: Overkill. This is a linear order, we could just count. Names are nice though,
	* and constants are also overkill...
	*
	* @see docs/pageupdater.md for documentation of the life cycle.
	*/
	private const TRANSITIONS = [
	'new' => [
	'new' => true,
	'knows-current' => true,
	'has-content' => true,
	'has-revision' => true,
	],
	'knows-current' => [
	'knows-current' => true,
	'has-content' => true,
	'has-revision' => true,
	],
	'has-content' => [
	'has-content' => true,
	'has-revision' => true,
	],
	'has-revision' => [
	'has-revision' => true,
	'done' => true,
	],
	];

	/** @var IContentHandlerFactory */
	private $contentHandlerFactory;

	/** @var EditResultCache */
	private $editResultCache;

	/** @var ContentTransformer */
	private $contentTransformer;

	/** @var PageEditStash */
	private $pageEditStash;

	/** @var WANObjectCache */
	private $mainWANObjectCache;

	/** @var bool */
	private $warmParsoidParserCache;

	/** @var bool */
	private $useRcPatrol;

	private ChangeTagsStore $changeTagsStore;

	public function __construct(
	ServiceOptions $options,
	PageIdentity $page,
	RevisionStore $revisionStore,
	RevisionRenderer $revisionRenderer,
	SlotRoleRegistry $slotRoleRegistry,
	ParserCache $parserCache,
	JobQueueGroup $jobQueueGroup,
	Language $contLang,
	ILBFactory $loadbalancerFactory,
	IContentHandlerFactory $contentHandlerFactory,
	HookContainer $hookContainer,
	DomainEventDispatcher $eventDispatcher,
	EditResultCache $editResultCache,
	ContentTransformer $contentTransformer,
	PageEditStash $pageEditStash,
	WANObjectCache $mainWANObjectCache,
	WikiPageFactory $wikiPageFactory,
	ChangeTagsStore $changeTagsStore
	) {
	// TODO: Remove this cast eventually
	$this->wikiPage = $wikiPageFactory->newFromTitle( $page );

	$this->parserCache = $parserCache;
	$this->revisionStore = $revisionStore;
	$this->revisionRenderer = $revisionRenderer;
	$this->slotRoleRegistry = $slotRoleRegistry;
	$this->jobQueueGroup = $jobQueueGroup;
	$this->contLang = $contLang;
	// XXX only needed for waiting for replicas to catch up; there should be a narrower
	// interface for that.
	$this->loadbalancerFactory = $loadbalancerFactory;
	$this->contentHandlerFactory = $contentHandlerFactory;
	$this->hookRunner = new HookRunner( $hookContainer );
	$this->eventDispatcher = $eventDispatcher;
	$this->editResultCache = $editResultCache;
	$this->contentTransformer = $contentTransformer;
	$this->pageEditStash = $pageEditStash;
	$this->mainWANObjectCache = $mainWANObjectCache;
	$this->changeTagsStore = $changeTagsStore;

	$this->logger = new NullLogger();

	$this->warmParsoidParserCache = $options
	->get( MainConfigNames::ParsoidCacheConfig )['WarmParsoidParserCache'];
	$this->useRcPatrol = $options
	->get( MainConfigNames::UseRCPatrol );
	}

	public function setLogger( LoggerInterface $logger ): void {
	$this->logger = $logger;
	}

	/**
	* Set the cause of the update. Will be used for the PageRevisionUpdatedEvent
	* and for tracing/logging in jobs, etc.
	*
	* @param string $cause See PageRevisionUpdatedEvent::CAUSE_XXX
	*
	* @return void
	*/
	public function setCause( string $cause ) {
	// 'cause' is for use in PageRevisionUpdatedEvent, 'causeAction' is for
	// use in tracing in updates, jobs, and RevisionRenderer.
	// Note that PageRevisionUpdatedEvent uses causes like "edit" and "move", but
	// the convention for causeAction is to use "page-edit", etc.
	$this->options['cause'] = $cause;
	$this->options['causeAction'] = 'page-' . $cause;
	}

	/**
	* Set the performer of the action.
	*
	* @return void
	*/
	public function setPerformer( UserIdentity $performer ) {
	$this->options['triggeringUser'] = $performer;
	$this->options['causeAgent'] = $performer->getName();
	}

	/**
	* @return string[] [ $causeAction, $causeAgent ]
	*/
	private function getCauseForTracing(): array {
	return [
	$this->options['causeAction'] ?? 'unknown',
	$this->options['causeAgent']
	?? ( $this->user ? $this->user->getName() : 'unknown' ),
	];
	}

	/**
	* Transition function for managing the life cycle of this instances.
	*
	* @see docs/pageupdater.md for documentation of the life cycle.
	*
	* @param string $newStage
	* @return string the previous stage
	*/
	private function doTransition( $newStage ) {
	$this->assertTransition( $newStage );

	$oldStage = $this->stage;
	$this->stage = $newStage;

	return $oldStage;
	}

	/**
	* Asserts that a transition to the given stage is possible, without performing it.
	*
	* @see docs/pageupdater.md for documentation of the life cycle.
	*
	* @param string $newStage
	*/
	private function assertTransition( $newStage ) {
	if ( empty( self::TRANSITIONS[$this->stage][$newStage] ) ) {
	throw new LogicException( "Cannot transition from {$this->stage} to $newStage" );
	}
	}

	/**
	* Checks whether this DerivedPageDataUpdater can be re-used for running updates targeting
	* the given revision.
	*
	* @param UserIdentity\|null $user The user creating the revision in question
	* @param RevisionRecord\|null $revision New revision (after save, if already saved)
	* @param RevisionSlotsUpdate\|null $slotsUpdate New content (before PST)
	* @param null\|int $parentId Parent revision of the edit (use 0 for page creation)
	*
	* @return bool
	*/
	public function isReusableFor(
	?UserIdentity $user = null,
	?RevisionRecord $revision = null,
	?RevisionSlotsUpdate $slotsUpdate = null,
	$parentId = null
	) {
	if ( $revision
	&& $parentId
	&& $revision->getParentId() !== $parentId
	) {
	throw new InvalidArgumentException( '$parentId should match the parent of $revision' );
	}

	// NOTE: For null revisions, $user may be different from $this->revision->getUser
	// and also from $revision->getUser.
	// But $user should always match $this->user.
	if ( $user && $this->user && $user->getName() !== $this->user->getName() ) {
	return false;
	}

	if ( $revision && $this->revision && $this->revision->getId()
	&& $this->revision->getId() !== $revision->getId()
	) {
	return false;
	}

	if ( $this->pageState
	&& $revision
	&& $revision->getParentId() !== null
	&& $this->pageState['oldId'] !== $revision->getParentId()
	) {
	return false;
	}

	if ( $this->pageState
	&& $parentId !== null
	&& $this->pageState['oldId'] !== $parentId
	) {
	return false;
	}

	// NOTE: this check is the primary reason for having the $this->slotsUpdate field!
	if ( $this->slotsUpdate
	&& $slotsUpdate
	&& !$this->slotsUpdate->hasSameUpdates( $slotsUpdate )
	) {
	return false;
	}

	if ( $revision
	&& $this->revision
	&& !$this->revision->getSlots()->hasSameContent( $revision->getSlots() )
	) {
	return false;
	}

	return true;
	}

	/**
	* Set whether null-edits should create a revision. Enabling this allows the creation of dummy
	* revisions ("null revisions") to mark events such as renaming in the page history.
	*
	* Must not be called once prepareContent() or prepareUpdate() have been called.
	*
	* @since 1.38
	* @see PageUpdater setForceEmptyRevision
	*
	* @param bool $forceEmptyRevision
	*/
	public function setForceEmptyRevision( bool $forceEmptyRevision ) {
	if ( $this->revision ) {
	throw new LogicException( 'prepareContent() or prepareUpdate() was already called.' );
	}

	$this->forceEmptyRevision = $forceEmptyRevision;
	}

	/**
	* @param string $articleCountMethod "any" or "link".
	* @see $wgArticleCountMethod
	*/
	public function setArticleCountMethod( $articleCountMethod ) {
	$this->articleCountMethod = $articleCountMethod;
	}

	/**
	* @return Title
	*/
	private function getTitle() {
	// NOTE: eventually, this won't use WikiPage any more
	return $this->wikiPage->getTitle();
	}

	/**
	* @return WikiPage
	*/
	private function getWikiPage() {
	// NOTE: eventually, this won't use WikiPage any more
	return $this->wikiPage;
	}

	/**
	* Returns the page being updated.
	* @since 1.37
	* @return ProperPageIdentity (narrowed to ProperPageIdentity in 1.44)
	*/
	public function getPage(): ProperPageIdentity {
	return $this->wikiPage;
	}

	/**
	* Determines whether the page being edited already existed.
	* Only defined after calling grabCurrentRevision() or prepareContent() or prepareUpdate()!
	*
	* @return bool
	* @throws LogicException if called before grabCurrentRevision
	*/
	public function pageExisted() {
	$this->assertHasPageState( __METHOD__ );

	return $this->pageState['oldId'] > 0;
	}

	/**
	* Returns the parent revision of the new revision wrapped by this update.
	* If the update is a null-edit, this will return the parent of the current (and new) revision.
	* This will return null if the revision wrapped by this update created the page.
	* Only defined after calling prepareContent() or prepareUpdate()!
	*
	* @return RevisionRecord\|null the parent revision of the new revision, or null if
	* the update created the page.
	*/
	private function getParentRevision() {
	$this->assertPrepared( __METHOD__ );

	if ( $this->parentRevision ) {
	return $this->parentRevision;
	}

	if ( !$this->pageState['oldId'] ) {
	// If there was no current revision, there is no parent revision,
	// since the page didn't exist.
	return null;
	}

	$oldId = $this->revision->getParentId();
	$flags = $this->usePrimary() ? IDBAccessObject::READ_LATEST : 0;
	$this->parentRevision = $oldId
	? $this->revisionStore->getRevisionById( $oldId, $flags )
	: null;

	return $this->parentRevision;
	}

	/**
	* Returns the revision that was the page's current revision when grabCurrentRevision()
	* was first called.
	*
	* @return RevisionRecord\|null the original revision before the update, or null
	* if the page did not yet exist.
	*/
	private function getOldRevision() {
	$this->assertPrepared( __METHOD__ );
	return $this->pageState['oldRevision'];
	}

	/**
	* Returns the revision that was the page's current revision when grabCurrentRevision()
	* was first called.
	*
	* During an edit, that revision will act as the logical parent of the new revision.
	*
	* Some updates are performed based on the difference between the database state at the
	* moment this method is first called, and the state after the edit.
	*
	* @see docs/pageupdater.md for more information on when thie method can and should be called.
	*
	* @note After prepareUpdate() was called, grabCurrentRevision() will throw an exception
	* to avoid confusion, since the page's current revision is then the new revision after
	* the edit, which was presumably passed to prepareUpdate() as the $revision parameter.
	* Use getParentRevision() instead to access the revision that is the parent of the
	* new revision.
	*
	* @return RevisionRecord\|null the page's current revision, or null if the page does not
	* yet exist.
	*/
	public function grabCurrentRevision() {
	if ( $this->pageState ) {
	return $this->pageState['oldRevision'];
	}

	$this->assertTransition( 'knows-current' );

	// NOTE: eventually, this won't use WikiPage any more
	$wikiPage = $this->getWikiPage();

	// Do not call WikiPage::clear(), since the caller may already have caused page data
	// to be loaded with SELECT FOR UPDATE. Just assert it's loaded now.
	$wikiPage->loadPageData( IDBAccessObject::READ_LATEST );
	$current = $wikiPage->getRevisionRecord();

	$this->pageState = [
	'oldRevision' => $current,
	'oldId' => $current ? $current->getId() : 0,
	'oldIsRedirect' => $wikiPage->isRedirect(), // NOTE: uses page table
	'oldCountable' => $wikiPage->isCountable(), // NOTE: uses pagelinks table
	'oldRecord' => $wikiPage->exists() ? $wikiPage->toPageRecord() : null,
	];

	$this->doTransition( 'knows-current' );

	return $this->pageState['oldRevision'];
	}

	/**
	* Whether prepareUpdate() or prepareContent() have been called on this instance.
	*
	* @return bool
	*/
	public function isContentPrepared() {
	return $this->revision !== null;
	}

	/**
	* Whether prepareUpdate() has been called on this instance.
	*
	* @note will also return null in case of a null-edit!
	*
	* @return bool
	*/
	public function isUpdatePrepared() {
	return $this->revision !== null && $this->revision->getId() !== null;
	}

	/**
	* @return int
	*/
	private function getPageId() {
	// NOTE: eventually, this won't use WikiPage any more
	return $this->wikiPage->getId();
	}

	/**
	* Whether the content is deleted and thus not visible to the public.
	*
	* @return bool
	*/
	public function isContentDeleted() {
	if ( $this->revision ) {
	return $this->revision->isDeleted( RevisionRecord::DELETED_TEXT );
	} else {
	// If the content has not been saved yet, it cannot have been deleted yet.
	return false;
	}
	}

	/**
	* Returns the slot, modified or inherited, after PST, with no audience checks applied.
	*
	* @param string $role slot role name
	*
	* @throws PageUpdateException If the slot is neither set for update nor inherited from the
	* parent revision.
	* @return SlotRecord
	*/
	public function getRawSlot( $role ) {
	return $this->getSlots()->getSlot( $role );
	}

	/**
	* Returns the content of the given slot, with no audience checks.
	*
	* @throws PageUpdateException If the slot is neither set for update nor inherited from the
	* parent revision.
	* @param string $role slot role name
	* @return Content
	*/
	public function getRawContent( string $role ): Content {
	return $this->getRawSlot( $role )->getContent();
	}

	private function usePrimary(): bool {
	// TODO: can we just set a flag to true in prepareContent()?
	return $this->wikiPage->wasLoadedFrom( IDBAccessObject::READ_LATEST );
	}

	public function isCountable(): bool {
	// NOTE: Keep in sync with WikiPage::isCountable.

	if ( !$this->getTitle()->isContentPage() ) {
	return false;
	}

	if ( $this->isContentDeleted() ) {
	// This should be irrelevant: countability only applies to the current revision,
	// and the current revision is never suppressed.
	return false;
	}

	if ( $this->isRedirect() ) {
	return false;
	}

	$hasLinks = null;

	if ( $this->articleCountMethod === 'link' ) {
	// NOTE: it would be more appropriate to determine for each slot separately
	// whether it has links, and use that information with that slot's
	// isCountable() method. However, that would break parity with
	// WikiPage::isCountable, which uses the pagelinks table to determine
	// whether the current revision has links.
	$hasLinks = $this->getParserOutputForMetaData()->hasLinks();
	}

	foreach ( $this->getSlots()->getSlotRoles() as $role ) {
	$roleHandler = $this->slotRoleRegistry->getRoleHandler( $role );
	if ( $roleHandler->supportsArticleCount() ) {
	$content = $this->getRawContent( $role );

	if ( $content->isCountable( $hasLinks ) ) {
	return true;
	}
	}
	}

	return false;
	}

	public function isRedirect(): bool {
	// NOTE: main slot determines redirect status
	// TODO: MCR: this should be controlled by a PageTypeHandler
	$mainContent = $this->getRawContent( SlotRecord::MAIN );

	return $mainContent->isRedirect();
	}

	/**
	* @param RevisionRecord $rev
	*
	* @return bool
	*/
	private function revisionIsRedirect( RevisionRecord $rev ) {
	// NOTE: main slot determines redirect status
	$mainContent = $rev->getMainContentRaw();

	return $mainContent->isRedirect();
	}

	/**
	* Prepare updates based on an update which has not yet been saved.
	*
	* This may be used to create derived data that is needed when creating a new revision;
	* particularly, this makes available the slots of the new revision via the getSlots()
	* method, after applying PST and slot inheritance.
	*
	* The derived data prepared for revision creation may then later be re-used by doUpdates(),
	* without the need to re-calculate.
	*
	* @see docs/pageupdater.md for more information on when thie method can and should be called.
	*
	* @note Calling this method more than once with the same $slotsUpdate
	* has no effect. Calling this method multiple times with different content will cause
	* an exception.
	*
	* @note Calling this method after prepareUpdate() has been called will cause an exception.
	*
	* @param UserIdentity $user The user to act as context for pre-save transformation (PST).
	* @param RevisionSlotsUpdate $slotsUpdate The new content of the slots to be updated
	* by this edit, before PST.
	* @param bool $useStash Whether to use stashed ParserOutput
	*/
	public function prepareContent(
	UserIdentity $user,
	RevisionSlotsUpdate $slotsUpdate,
	$useStash = true
	) {
	if ( $this->slotsUpdate ) {
	if ( !$this->user ) {
	throw new LogicException(
	'Unexpected state: $this->slotsUpdate was initialized, '
	. 'but $this->user was not.'
	);
	}

	if ( $this->user->getName() !== $user->getName() ) {
	throw new LogicException( 'Can\'t call prepareContent() again for different user! '
	. 'Expected ' . $this->user->getName() . ', got ' . $user->getName()
	);
	}

	if ( !$this->slotsUpdate->hasSameUpdates( $slotsUpdate ) ) {
	throw new LogicException(
	'Can\'t call prepareContent() again with different slot content!'
	);
	}

	return; // prepareContent() already done, nothing to do
	}

	$this->assertTransition( 'has-content' );

	$wikiPage = $this->getWikiPage(); // TODO: use only for legacy hooks!
	$title = $this->getTitle();

	$parentRevision = $this->grabCurrentRevision();

	// The edit may have already been prepared via api.php?action=stashedit
	$stashedEdit = false;

	// TODO: MCR: allow output for all slots to be stashed.
	if ( $useStash && $slotsUpdate->isModifiedSlot( SlotRecord::MAIN ) ) {
	$stashedEdit = $this->pageEditStash->checkCache(
	$title,
	$slotsUpdate->getModifiedSlot( SlotRecord::MAIN )->getContent(),
	$user
	);
	}

	$userPopts = ParserOptions::newFromUserAndLang( $user, $this->contLang );
	$userPopts->setRenderReason( $this->options['causeAgent'] ?? 'unknown' );

	$this->hookRunner->onArticlePrepareTextForEdit( $wikiPage, $userPopts );

	$this->user = $user;
	$this->slotsUpdate = $slotsUpdate;

	if ( $parentRevision ) {
	$this->revision = MutableRevisionRecord::newFromParentRevision( $parentRevision );
	} else {
	$this->revision = new MutableRevisionRecord( $title );
	}

	// NOTE: user and timestamp must be set, so they can be used for
	// {{subst:REVISIONUSER}} and {{subst:REVISIONTIMESTAMP}} in PST!
	$this->revision->setTimestamp( MWTimestamp::now( TS_MW ) );
	$this->revision->setUser( $user );

	// Set up ParserOptions to operate on the new revision
	$oldCallback = $userPopts->getCurrentRevisionRecordCallback();
	$userPopts->setCurrentRevisionRecordCallback(
	function ( Title $parserTitle, $parser = null ) use ( $title, $oldCallback ) {
	if ( $parserTitle->equals( $title ) ) {
	return $this->revision;
	} else {
	return $oldCallback( $parserTitle, $parser );
	}
	}
	);

	$pstContentSlots = $this->revision->getSlots();

	foreach ( $slotsUpdate->getModifiedRoles() as $role ) {
	$slot = $slotsUpdate->getModifiedSlot( $role );

	if ( $slot->isInherited() ) {
	// No PST for inherited slots! Note that "modified" slots may still be inherited
	// from an earlier version, e.g. for rollbacks.
	$pstSlot = $slot;
	} elseif ( $role === SlotRecord::MAIN && $stashedEdit ) {
	// TODO: MCR: allow PST content for all slots to be stashed.
	$pstSlot = SlotRecord::newUnsaved( $role, $stashedEdit->pstContent );
	} else {
	$pstContent = $this->contentTransformer->preSaveTransform(
	$slot->getContent(),
	$title,
	$user,
	$userPopts
	);

	$pstSlot = SlotRecord::newUnsaved( $role, $pstContent );
	}

	$pstContentSlots->setSlot( $pstSlot );
	}

	foreach ( $slotsUpdate->getRemovedRoles() as $role ) {
	$pstContentSlots->removeSlot( $role );
	}

	$this->options['created'] = ( $parentRevision === null );
	$this->options['changed'] = ( $parentRevision === null
	\|\| !$pstContentSlots->hasSameContent( $parentRevision->getSlots() ) );

	$this->doTransition( 'has-content' );

	if ( !$this->options['changed'] ) {
	if ( $this->forceEmptyRevision ) {
	// dummy revision, inherit all slots
	foreach ( $parentRevision->getSlotRoles() as $role ) {
	$this->revision->inheritSlot( $parentRevision->getSlot( $role ) );
	}
	} else {
	// null-edit, the new revision is the old revision.

	// TODO: move this into MutableRevisionRecord
	$this->revision->setId( $parentRevision->getId() );
	$this->revision->setTimestamp( $parentRevision->getTimestamp() );
	$this->revision->setPageId( $parentRevision->getPageId() );
	$this->revision->setParentId( $parentRevision->getParentId() );
	$this->revision->setUser( $parentRevision->getUser( RevisionRecord::RAW ) );
	$this->revision->setComment( $parentRevision->getComment( RevisionRecord::RAW ) );
	$this->revision->setMinorEdit( $parentRevision->isMinor() );
	$this->revision->setVisibility( $parentRevision->getVisibility() );

	// prepareUpdate() is redundant for null-edits (but not for dummy revisions)
	$this->doTransition( 'has-revision' );
	}
	} else {
	$this->parentRevision = $parentRevision;
	}

	$renderHints = [ 'use-master' => $this->usePrimary(), 'audience' => RevisionRecord::RAW ];

	if ( $stashedEdit ) {
	/** @var ParserOutput $output */
	$output = $stashedEdit->output;
	// TODO: this should happen when stashing the ParserOutput, not now!
	$output->setCacheTime( $stashedEdit->timestamp );

	$renderHints['known-revision-output'] = $output;

	$this->logger->debug( __METHOD__ . ': using stashed edit output...' );
	}

	$renderHints['generate-html'] = $this->shouldGenerateHTMLOnEdit();

	[ $causeAction, ] = $this->getCauseForTracing();
	$renderHints['causeAction'] = $causeAction;

	// NOTE: we want a canonical rendering, so don't pass $this->user or ParserOptions
	// NOTE: the revision is either new or current, so we can bypass audience checks.
	$this->renderedRevision = $this->revisionRenderer->getRenderedRevision(
	$this->revision,
	null,
	null,
	$renderHints
	);
	}

	/**
	* Returns the update's target revision - that is, the revision that will be the current
	* revision after the update.
	*
	* @note Callers must treat the returned RevisionRecord's content as immutable, even
	* if it is a MutableRevisionRecord instance. Other aspects of a MutableRevisionRecord
	* returned from here, such as the user or the comment, may be changed, but may not
	* be reflected in ParserOutput until after prepareUpdate() has been called.
	*
	* @todo This is currently used by PageUpdater::makeNewRevision() to construct an unsaved
	* MutableRevisionRecord instance. Introduce something like an UnsavedRevisionFactory service
	* for that purpose instead!
	*
	* @return RevisionRecord
	*/
	public function getRevision(): RevisionRecord {
	$this->assertPrepared( __METHOD__ );
	return $this->revision;
	}

	public function getRenderedRevision(): RenderedRevision {
	$this->assertPrepared( __METHOD__ );

	return $this->renderedRevision;
	}

	private function assertHasPageState( string $method ) {
	if ( !$this->pageState ) {
	throw new LogicException(
	'Must call grabCurrentRevision() or prepareContent() '
	. 'or prepareUpdate() before calling ' . $method
	);
	}
	}

	private function assertPrepared( string $method ) {
	if ( !$this->revision ) {
	throw new LogicException(
	'Must call prepareContent() or prepareUpdate() before calling ' . $method
	);
	}
	}

	private function assertHasRevision( string $method ) {
	if ( !$this->revision->getId() ) {
	throw new LogicException(
	'Must call prepareUpdate() before calling ' . $method
	);
	}
	}

	/**
	* Whether the edit creates the page.
	*
	* @return bool
	*/
	public function isCreation() {
	$this->assertPrepared( __METHOD__ );
	return $this->options['created'];
	}

	/**
	* Whether the content of the current revision after the edit is different from the content of the
	* current revision before the edit. This will return false for a null-edit (no revision created),
	* as well as for a dummy revision (a "null-revision" that has the same content as its parent).
	*
	* @warning at present, dummy revision would return false after prepareContent(),
	* but true after prepareUpdate()!
	*
	* @todo This should probably be fixed.
	*
	* @return bool
	*/
	public function isChange() {
	$this->assertPrepared( __METHOD__ );
	return $this->options['changed'];
	}

	/**
	* Whether the page was a redirect before the edit.
	*
	* @return bool
	*/
	public function wasRedirect() {
	$this->assertHasPageState( __METHOD__ );

	if ( $this->pageState['oldIsRedirect'] === null ) {
	/** @var RevisionRecord $rev */
	$rev = $this->pageState['oldRevision'];
	if ( $rev ) {
	$this->pageState['oldIsRedirect'] = $this->revisionIsRedirect( $rev );
	} else {
	$this->pageState['oldIsRedirect'] = false;
	}
	}

	return $this->pageState['oldIsRedirect'];
	}

	/**
	* Returns the slots of the target revision, after PST.
	*
	* @note Callers must treat the returned RevisionSlots instance as immutable, even
	* if it is a MutableRevisionSlots instance.
	*
	* @return RevisionSlots
	*/
	public function getSlots() {
	$this->assertPrepared( __METHOD__ );
	return $this->revision->getSlots();
	}

	/**
	* Returns the RevisionSlotsUpdate for this updater.
	*
	* @return RevisionSlotsUpdate
	*/
	private function getRevisionSlotsUpdate() {
	$this->assertPrepared( __METHOD__ );

	if ( !$this->slotsUpdate ) {
	$old = $this->getParentRevision();
	$this->slotsUpdate = RevisionSlotsUpdate::newFromRevisionSlots(
	$this->revision->getSlots(),
	$old ? $old->getSlots() : null
	);
	}
	return $this->slotsUpdate;
	}

	/**
	* Returns the role names of the slots touched by the new revision,
	* including removed roles.
	*
	* @return string[]
	*/
	public function getTouchedSlotRoles() {
	return $this->getRevisionSlotsUpdate()->getTouchedRoles();
	}

	/**
	* Returns the role names of the slots modified by the new revision,
	* not including removed roles.
	*
	* @return string[]
	*/
	public function getModifiedSlotRoles(): array {
	return $this->getRevisionSlotsUpdate()->getModifiedRoles();
	}

	/**
	* Returns the role names of the slots removed by the new revision.
	*
	* @return string[]
	*/
	public function getRemovedSlotRoles(): array {
	return $this->getRevisionSlotsUpdate()->getRemovedRoles();
	}

	/**
	* Prepare derived data updates targeting the given RevisionRecord.
	*
	* Calling this method requires the given revision to be present in the database.
	* This may be right after a new revision has been created, or when re-generating
	* derived data e.g. in ApiPurge, RefreshLinksJob, and the refreshLinks
	* script.
	*
	* @see docs/pageupdater.md for more information on when thie method can and should be called.
	*
	* @note Calling this method more than once with the same revision has no effect.
	* $options are only used for the first call. Calling this method multiple times with
	* different revisions will cause an exception.
	*
	* @note If grabCurrentRevision() (or prepareContent()) has been called before
	* calling this method, $revision->getParentRevision() has to refer to the revision that
	* was the current revision at the time grabCurrentRevision() was called.
	*
	* @param RevisionRecord $revision
	* @param array $options Array of options. Supports the flags defined by
	* PageRevisionUpdatedEvent. In addition, the following keys are supported used:
	* - oldtitle: PageIdentity, if the page was moved this is the source title (default null)
	* - oldrevision: RevisionRecord object for the pre-update revision (default null)
	* - triggeringUser: The user triggering the update (UserIdentity, defaults to the
	* user who created the revision)
	* - oldredirect: bool, null, or string 'no-change' (default null):
	* - bool: whether the page was counted as a redirect before that
	* revision, only used in changed is true and created is false
	* - null or 'no-change': don't update the redirect status.
	* - oldcountable: bool, null, or string 'no-change' (default null):
	* - bool: whether the page was counted as an article before that
	* revision, only used in changed is true and created is false
	* - null: if created is false, don't update the article count; if created
	* is true, do update the article count
	* - 'no-change': don't update the article count, ever
	* When set to null, pageState['oldCountable'] will be used instead if available.
	* - cause: the reason for the update, see PageRevisionUpdatedEvent::CAUSE_XXX.
	* - known-revision-output: a combined canonical ParserOutput for the revision, perhaps
	* from some cache. The caller is responsible for ensuring that the ParserOutput indeed
	* matched the $rev and $options. This mechanism is intended as a temporary stop-gap,
	* for the time until caches have been changed to store RenderedRevision states instead
	* of ParserOutput objects. (default: null) (since 1.33)
	* - editResult: EditResult object created during the update. Required to perform reverted
	* tag update using RevertedTagUpdateJob. (default: null) (since 1.36)
	*/
	public function prepareUpdate( RevisionRecord $revision, array $options = [] ) {
	Assert::parameter(
	!isset( $options['oldrevision'] )
	\|\| $options['oldrevision'] instanceof RevisionRecord,
	'$options["oldrevision"]',
	'must be a RevisionRecord'
	);
	Assert::parameter(
	!isset( $options['triggeringUser'] )
	\|\| $options['triggeringUser'] instanceof UserIdentity,
	'$options["triggeringUser"]',
	'must be a UserIdentity'
	);
	Assert::parameter(
	!isset( $options['editResult'] )
	\|\| $options['editResult'] instanceof EditResult,
	'$options["editResult"]',
	'must be an EditResult'
	);

	if ( !$revision->getId() ) {
	throw new InvalidArgumentException(
	'Revision must have an ID set for it to be used with prepareUpdate()!'
	);
	}

	if ( !$this->wikiPage->exists() ) {
	// If the ongoing edit is creating the page, the state of $this->wikiPage
	// may be out of whack. This would only happen if the page creation was
	// done using a different WikiPage instance, which shouldn't be the case.
	$this->logger->warning(
	__METHOD__ . ': Reloading page meta-data after page creation',
	[
	'page' => (string)$this->wikiPage,
	'rev_id' => $revision->getId(),
	]
	);

	$this->wikiPage->clear();
	$this->wikiPage->loadPageData( IDBAccessObject::READ_LATEST );
	}

	if ( $this->revision && $this->revision->getId() ) {
	if ( $this->revision->getId() === $revision->getId() ) {
	$this->options['changed'] = false; // null-edit
	} else {
	throw new LogicException(
	'Trying to re-use DerivedPageDataUpdater with revision '
	. $revision->getId()
	. ', but it\'s already bound to revision '
	. $this->revision->getId()
	);
	}
	}

	if ( $this->revision
	&& !$this->revision->getSlots()->hasSameContent( $revision->getSlots() )
	) {
	throw new LogicException(
	'The revision provided has mismatching content!'
	);
	}

	// Override fields defined in $this->options with values from $options.
	$this->options = array_intersect_key( $options, $this->options ) + $this->options;

	if ( $this->revision ) {
	$oldId = $this->pageState['oldId'] ?? 0;
	$this->options['newrev'] = ( $revision->getId() !== $oldId );
	} elseif ( isset( $this->options['oldrevision'] ) ) {
	/** @var RevisionRecord $oldRev */
	$oldRev = $this->options['oldrevision'];
	$oldId = $oldRev->getId();
	$this->options['newrev'] = ( $revision->getId() !== $oldId );
	} else {
	$oldId = $revision->getParentId();
	}

	if ( $oldId !== null ) {
	// XXX: what if $options['changed'] disagrees?
	// MovePage creates a dummy revision with changed = false!
	// We may want to explicitly distinguish between "no new revision" (null-edit)
	// and "new revision without new content" (dummy revision).

	if ( $oldId === $revision->getParentId() ) {
	// NOTE: this may still be a NullRevision!
	// New revision!
	$this->options['changed'] = true;
	} elseif ( $oldId === $revision->getId() ) {
	// Null-edit!
	$this->options['changed'] = false;
	} else {
	// This indicates that calling code has given us the wrong RevisionRecord object
	throw new LogicException(
	'The RevisionRecord mismatches old revision ID: '
	. 'Old ID is ' . $oldId
	. ', parent ID is ' . $revision->getParentId()
	. ', revision ID is ' . $revision->getId()
	);
	}
	}

	// If prepareContent() was used to generate the PST content (which is indicated by
	// $this->slotsUpdate being set), and this is not a null-edit, then the given
	// revision must have the acting user as the revision author. Otherwise, user
	// signatures generated by PST would mismatch the user in the revision record.
	if ( $this->user !== null && $this->options['changed'] && $this->slotsUpdate ) {
	$user = $revision->getUser();
	if ( !$this->user->equals( $user ) ) {
	throw new LogicException(
	'The RevisionRecord provided has a mismatching actor: expected '
	. $this->user->getName()
	. ', got '
	. $user->getName()
	);
	}
	}

	// If $this->pageState was not yet initialized by grabCurrentRevision or prepareContent,
	// emulate the state of the page table before the edit, as good as we can.
	if ( !$this->pageState ) {
	$this->pageState = [
	'oldIsRedirect' => isset( $this->options['oldredirect'] )
	&& is_bool( $this->options['oldredirect'] )
	? $this->options['oldredirect']
	: null,
	'oldCountable' => isset( $this->options['oldcountable'] )
	&& is_bool( $this->options['oldcountable'] )
	? $this->options['oldcountable']
	: null,
	];

	if ( $this->options['changed'] ) {
	// The edit created a new revision
	$this->pageState['oldId'] = $revision->getParentId();
	// Old revision is null if this is a page creation
	$this->pageState['oldRevision'] = $this->options['oldrevision'] ?? null;
	} else {
	// This is a null-edit, so the old revision IS the new revision!
	$this->pageState['oldId'] = $revision->getId();
	$this->pageState['oldRevision'] = $revision;
	}
	}

	// "created" is forced here
	$this->options['created'] = ( $this->options['created'] \|\|
	( $this->pageState['oldId'] === 0 ) );

	$this->revision = $revision;

	$this->doTransition( 'has-revision' );

	// NOTE: in case we have a User object, don't override with a UserIdentity.
	// We already checked that $revision->getUser() matches $this->user;
	if ( !$this->user ) {
	$this->user = $revision->getUser( RevisionRecord::RAW );
	}

	// Prune any output that depends on the revision ID.
	if ( $this->renderedRevision ) {
	$this->renderedRevision->updateRevision( $revision );
	} else {
	[ $causeAction, ] = $this->getCauseForTracing();
	// NOTE: we want a canonical rendering, so don't pass $this->user or ParserOptions
	// NOTE: the revision is either new or current, so we can bypass audience checks.
	$this->renderedRevision = $this->revisionRenderer->getRenderedRevision(
	$this->revision,
	null,
	null,
	[
	'use-master' => $this->usePrimary(),
	'audience' => RevisionRecord::RAW,
	'known-revision-output' => $options['known-revision-output'] ?? null,
	'causeAction' => $causeAction
	]
	);

	// XXX: Since we presumably are dealing with the current revision,
	// we could try to get the ParserOutput from the parser cache.
	}

	// TODO: optionally get ParserOutput from the ParserCache here.
	// Move the logic used by RefreshLinksJob here!
	}

	/**
	* @deprecated since 1.43; This only exists for B/C, use the getters on DerivedPageDataUpdater directly!
	* @return PreparedEdit
	*/
	public function getPreparedEdit() {
	$this->assertPrepared( __METHOD__ );

	$slotsUpdate = $this->getRevisionSlotsUpdate();
	$preparedEdit = new PreparedEdit();

	$preparedEdit->popts = $this->getCanonicalParserOptions();
	$preparedEdit->parserOutputCallback = [ $this, 'getCanonicalParserOutput' ];
	$preparedEdit->pstContent = $this->revision->getContent( SlotRecord::MAIN );
	$preparedEdit->newContent =
	$slotsUpdate->isModifiedSlot( SlotRecord::MAIN )
	? $slotsUpdate->getModifiedSlot( SlotRecord::MAIN )->getContent()
	: $this->revision->getContent( SlotRecord::MAIN ); // XXX: can we just remove this?
	$preparedEdit->oldContent = null; // unused. // XXX: could get this from the parent revision
	$preparedEdit->revid = $this->revision ? $this->revision->getId() : null;
	$preparedEdit->format = $preparedEdit->pstContent->getDefaultFormat();

	return $preparedEdit;
	}

	/**
	* @param string $role
	* @param bool $generateHtml
	* @return ParserOutput
	*/
	public function getSlotParserOutput( $role, $generateHtml = true ) {
	return $this->getRenderedRevision()->getSlotParserOutput(
	$role,
	[ 'generate-html' => $generateHtml ]
	);
	}

	/**
	* @since 1.37
	* @return ParserOutput
	*/
	public function getParserOutputForMetaData(): ParserOutput {
	return $this->getRenderedRevision()->getRevisionParserOutput( [ 'generate-html' => false ] );
	}

	/**
	* @inheritDoc
	* @return ParserOutput
	*/
	public function getCanonicalParserOutput(): ParserOutput {
	return $this->getRenderedRevision()->getRevisionParserOutput();
	}

	public function getCanonicalParserOptions(): ParserOptions {
	return $this->getRenderedRevision()->getOptions();
	}

	/**
	* @param bool $recursive
	*
	* @return DeferrableUpdate[]
	*/
	public function getSecondaryDataUpdates( $recursive = false ) {
	if ( $this->isContentDeleted() ) {
	// This shouldn't happen, since the current content is always public,
	// and DataUpdates are only needed for current content.
	return [];
	}

	$wikiPage = $this->getWikiPage();
	$wikiPage->loadPageData( IDBAccessObject::READ_LATEST );
	if ( !$wikiPage->exists() ) {
	// page deleted while deferring the update
	return [];
	}

	$title = $wikiPage->getTitle();
	$allUpdates = [];
	$parserOutput = $this->shouldGenerateHTMLOnEdit() ?
	$this->getCanonicalParserOutput() : $this->getParserOutputForMetaData();

	// Construct a LinksUpdate for the combined canonical output.
	$linksUpdate = new LinksUpdate(
	$title,
	$parserOutput,
	$recursive,
	// Redirect target may have changed if the page is or was a redirect.
	// (We can't check if it was definitely changed without additional queries.)
	$this->isRedirect() \|\| $this->wasRedirect()
	);
	if ( $this->options['cause'] === PageRevisionUpdatedEvent::CAUSE_MOVE ) {
	// @phan-suppress-next-line PhanTypeMismatchArgument Oldtitle is set along with moved
	$linksUpdate->setMoveDetails( $this->options['oldtitle'] );
	}

	$allUpdates[] = $linksUpdate;
	// NOTE: Run updates for all slots, not just the modified slots! Otherwise,
	// info for an inherited slot may end up being removed. This is also needed
	// to ensure that purges are effective.
	$renderedRevision = $this->getRenderedRevision();

	foreach ( $this->getSlots()->getSlotRoles() as $role ) {
	$slot = $this->getRawSlot( $role );
	$content = $slot->getContent();
	$handler = $content->getContentHandler();

	$updates = $handler->getSecondaryDataUpdates(
	$title,
	$content,
	$role,
	$renderedRevision
	);

	$allUpdates = array_merge( $allUpdates, $updates );
	}

	// XXX: if a slot was removed by an earlier edit, but deletion updates failed to run at
	// that time, we don't know for which slots to run deletion updates when purging a page.
	// We'd have to examine the entire history of the page to determine that. Perhaps there
	// could be a "try extra hard" mode for that case that would run a DB query to find all
	// roles/models ever used on the page. On the other hand, removing slots should be quite
	// rare, so perhaps this isn't worth the trouble.

	// TODO: consolidate with similar logic in WikiPage::getDeletionUpdates()
	$parentRevision = $this->getParentRevision();
	foreach ( $this->getRemovedSlotRoles() as $role ) {
	// HACK: we should get the content model of the removed slot from a SlotRoleHandler!
	// For now, find the slot in the parent revision - if the slot was removed, it should
	// always exist in the parent revision.
	$parentSlot = $parentRevision->getSlot( $role, RevisionRecord::RAW );
	$content = $parentSlot->getContent();
	$handler = $content->getContentHandler();

	$updates = $handler->getDeletionUpdates(
	$title,
	$role
	);

	$allUpdates = array_merge( $allUpdates, $updates );
	}

	// TODO: hard deprecate SecondaryDataUpdates in favor of RevisionDataUpdates in 1.33!
	$this->hookRunner->onRevisionDataUpdates( $title, $renderedRevision, $allUpdates );

	return $allUpdates;
	}

	/**
	* @return bool true if at least one of slots require rendering HTML on edit, false otherwise.
	* This is needed for example in populating ParserCache.
	*/
	private function shouldGenerateHTMLOnEdit(): bool {
	foreach ( $this->getSlots()->getSlotRoles() as $role ) {
	$slot = $this->getRawSlot( $role );
	$contentHandler = $this->contentHandlerFactory->getContentHandler( $slot->getModel() );
	if ( $contentHandler->generateHTMLOnEdit() ) {
	return true;
	}
	}
	return false;
	}

	/**
	* Do standard updates after page edit, purge, or import.
	* Update links tables and other derived data.
	* Purges pages that depend on this page when appropriate.
	* With a 10% chance, triggers pruning the recent changes table.
	*
	* Further updates may be triggered by core components and extensions
	* that listen to the PageRevisionUpdated event. Search for method names
	* starting with "handlePageRevisionUpdatedEvent" to find listeners.
	*
	* @note prepareUpdate() must be called before calling this method!
	*
	* MCR migration note: this replaces WikiPage::doEditUpdates.
	*/
	public function doUpdates() {
	$this->assertTransition( 'done' );

	if ( $this->options['emitEvents'] ) {
	$this->emitEvents();
	}

	// TODO: move more logic into ingress objects subscribed to PageRevisionUpdatedEvent!
	$event = $this->getPageRevisionUpdatedEvent();

	if ( $this->shouldGenerateHTMLOnEdit() ) {
	$this->triggerParserCacheUpdate();
	}

	$this->doSecondaryDataUpdates( [
	// T52785 do not update any other pages on dummy revisions and null edits
	'recursive' => $event->isEffectiveContentChange(),
	// Defer the getCanonicalParserOutput() call made by getSecondaryDataUpdates()
	'defer' => DeferredUpdates::POSTSEND
	] );

	$id = $this->getPageId();
	$title = $this->getTitle();
	$wikiPage = $this->getWikiPage();

	if ( !$title->exists() ) {
	wfDebug( __METHOD__ . ": Page doesn't exist any more, bailing out" );

	$this->doTransition( 'done' );
	return;
	}

	DeferredUpdates::addCallableUpdate( function () use ( $event ) {
	if (
	$this->options['oldcountable'] === 'no-change' \|\|
	( !$event->isEffectiveContentChange() && !$event->hasCause( PageRevisionUpdatedEvent::CAUSE_MOVE ) )
	) {
	$good = 0;
	} elseif ( $event->isCreation() ) {
	$good = (int)$this->isCountable();
	} elseif ( $this->options['oldcountable'] !== null ) {
	$good = (int)$this->isCountable()
	- (int)$this->options['oldcountable'];
	} elseif ( isset( $this->pageState['oldCountable'] ) ) {
	$good = (int)$this->isCountable()
	- (int)$this->pageState['oldCountable'];
	} else {
	$good = 0;
	}
	$edits = $event->isEffectiveContentChange() ? 1 : 0;
	$pages = $event->isCreation() ? 1 : 0;

	DeferredUpdates::addUpdate( SiteStatsUpdate::factory(
	[ 'edits' => $edits, 'articles' => $good, 'pages' => $pages ]
	) );
	} );

	// TODO: move onArticleCreate and onArticleEdit into a PageEventEmitter service
	if ( $event->isCreation() ) {
	// Deferred update that adds a mw-recreated tag to edits that create new pages
	// which have an associated deletion log entry for the specific namespace/title combination
	// and which are not undeletes
	if ( !( $event->hasCause( PageRevisionUpdatedEvent::CAUSE_UNDELETE ) ) ) {
	$revision = $this->revision;
	DeferredUpdates::addCallableUpdate( function () use ( $revision, $wikiPage ) {
	$this->maybeAddRecreateChangeTag( $wikiPage, $revision->getId() );
	} );
	}
	WikiPage::onArticleCreate( $title, $this->isRedirect() );
	} elseif ( $event->isEffectiveContentChange() ) { // T52785
	// TODO: Check $event->isNominalContentChange() instead so we still
	// trigger updates on null edits, but pass a flag to suppress
	// backlink purges through queueBacklinksJobs() id
	// $event->changedLatestRevisionId() returns false.
	WikiPage::onArticleEdit(
	$title,
	$this->revision,
	$this->getTouchedSlotRoles(),
	// Redirect target may have changed if the page is or was a redirect.
	// (We can't check if it was definitely changed without additional queries.)
	$this->isRedirect() \|\| $this->wasRedirect()
	);
	}

	if ( $event->hasCause( PageRevisionUpdatedEvent::CAUSE_UNDELETE ) ) {
	$this->mainWANObjectCache->touchCheckKey(
	"DerivedPageDataUpdater:restore:page:$id"
	);
	}

	$editResult = $event->getEditResult();

	if ( $editResult && !$editResult->isNullEdit() ) {
	// Cache EditResult for future use, via
	// RevertTagUpdateManager::approveRevertedTagForRevision().
	// This drives RevertedTagUpdateManager::approveRevertedTagForRevision.
	// It is only needed if RCPatrolling is enabled and the edit is a revert.
	// Skip in other cases to avoid flooding the cache, see T386217 and T388573.
	if ( $editResult->isRevert() && $this->useRcPatrol ) {
	$this->editResultCache->set(
	$this->revision->getId(),
	$editResult
	);
	}
	}

	$this->doTransition( 'done' );
	}

	/**
	* @internal
	*/
	public function emitEvents(): void {
	if ( !$this->options['emitEvents'] ) {
	throw new LogicException( 'emitEvents was disabled on this updater' );
	}

	$event = $this->getPageRevisionUpdatedEvent();

	// don't dispatch again!
	$this->options['emitEvents'] = false;

	$this->eventDispatcher->dispatch( $event, $this->loadbalancerFactory );
	}

	private function getPageRevisionUpdatedEvent(): PageRevisionUpdatedEvent {
	if ( $this->pageRevisionUpdatedEvent ) {
	return $this->pageRevisionUpdatedEvent;
	}

	$this->assertHasRevision( __METHOD__ );

	$flags = array_intersect_key(
	$this->options,
	PageRevisionUpdatedEvent::DEFAULT_FLAGS
	);

	$pageRecordBefore = $this->pageState['oldRecord'] ?? null;
	$pageRecordAfter = $this->getWikiPage()->toPageRecord();

	$revisionBefore = $this->getOldRevision();
	$revisionAfter = $this->getRevision();

	if ( $this->options['created'] ) {
	// Page creation. No prior state.
	// Force null to make sure we don't get confused during imports when
	// updates are triggered after importing the last revision of several.
	// In that case, the page and older revisions do already exist when
	// the DerivedPageDataUpdater is initialized, because they were
	// created during the import. But they didn't exist prior to the
	// import (based on the fact that the 'created' flag is set).
	$pageRecordBefore = null;
	$revisionBefore = null;
	} elseif ( !$this->options['changed'] ) {
	// Null edit. Should already be the same, just make sure.
	$pageRecordBefore = $pageRecordAfter;
	}

	if ( $revisionBefore && $revisionAfter->getId() === $revisionBefore->getId() ) {
	// This is a null edit, flag it as a reconciliation request.
	$flags[ PageRevisionUpdatedEvent::FLAG_RECONCILIATION_REQUEST ] = true;
	}

	if ( $pageRecordBefore === null && !$this->options['created'] ) {
	// If the page wasn't just created, we need the state before.
	// If we are not actually emitting the event, we can ignore the issue.
	// This is needed to support the deprecated WikiPage::doEditUpdates()
	// method. Once that is gone, we can remove this conditional.
	if ( $this->options['emitEvents'] ) {
	throw new LogicException( 'Missing page state before update' );
	}
	}

	/** @var UserIdentity $performer */
	$performer = $this->options['triggeringUser'] ?? $this->user;
	'@phan-var UserIdentity $performer';

	$this->pageRevisionUpdatedEvent = new PageRevisionUpdatedEvent(
	$this->options['cause'] ?? PageUpdateCauses::CAUSE_EDIT,
	$pageRecordBefore,
	$pageRecordAfter,
	$revisionBefore,
	$revisionAfter,
	$this->getRevisionSlotsUpdate(),
	$this->options['editResult'] ?? null,
	$performer,
	$this->options['tags'] ?? [],
	$flags,
	$this->options['rcPatrolStatus'] ?? 0,
	);

	return $this->pageRevisionUpdatedEvent;
	}

	private function triggerParserCacheUpdate() {
	$this->assertHasRevision( __METHOD__ );

	$userParserOptions = ParserOptions::newFromUser( $this->user );

	// Decide whether to save the final canonical parser output based on the fact that
	// users are typically redirected to viewing pages right after they edit those pages.
	// Due to vary-revision-id, getting/saving that output here might require a reparse.
	if ( $userParserOptions->matchesForCacheKey( $this->getCanonicalParserOptions() ) ) {
	// Whether getting the final output requires a reparse or not, the user will
	// need canonical output anyway, since that is what their parser options use.
	// A reparse now at least has the benefit of various warm process caches.
	$this->doParserCacheUpdate();
	} else {
	// If the user does not have canonical parse options, then don't risk another parse
	// to make output they cannot use on the page refresh that typically occurs after
	// editing. Doing the parser output save post-send will still benefit other users.
	DeferredUpdates::addCallableUpdate( function () {
	$this->doParserCacheUpdate();
	} );
	}
	}

	/**
	* Checks deletion logs for the specific article title and namespace combination
	* if a deletion log exists, we can assume this is a new page recreation and are tagging it with `mw-recreated`.
	* This does not consider deletions that were suppressed and therefore will not tag those.
	*
	* @param WikiPage $wikiPage
	* @param int $revisionId
	*/
	private function maybeAddRecreateChangeTag( WikiPage $wikiPage, int $revisionId ) {
	$dbr = $this->loadbalancerFactory->getReplicaDatabase();

	if ( $dbr->newSelectQueryBuilder()
	->select( [ '1' ] )
	->from( 'logging' )
	->where( [
	'log_type' => 'delete',
	'log_title' => $wikiPage->getTitle()->getDBkey(),
	'log_namespace' => $wikiPage->getNamespace(),
	] )
	->where(
	$dbr->bitAnd( 'log_deleted', LogPage::DELETED_ACTION ) .
	' != ' . LogPage::DELETED_ACTION // T385792
	)->caller( __METHOD__ )->limit( 1 )->fetchField() ) {
	$this->changeTagsStore->addTags(
	[ ChangeTags::TAG_RECREATE ],
	null,
	$revisionId );
	}
	}

	/**
	* Do secondary data updates (e.g. updating link tables) or schedule them as deferred updates
	*
	* @note This does not update the parser cache. Use doParserCacheUpdate() for that.
	* @note Application logic should use Wikipage::doSecondaryDataUpdates instead.
	*
	* @param array $options
	* - recursive: make the update recursive, i.e. also update pages which transclude the
	* current page or otherwise depend on it (default: false)
	* - defer: one of the DeferredUpdates constants, or false to run immediately after waiting
	* for replication of the changes from the SecondaryDataUpdates hooks (default: false)
	* - freshness: used with 'defer'; forces an update if the last update was before the given timestamp,
	* even if the page and its dependencies didn't change since then (TS_MW; default: false)
	* @since 1.32
	*/
	public function doSecondaryDataUpdates( array $options = [] ) {
	$this->assertHasRevision( __METHOD__ );
	$options += [ 'recursive' => false, 'defer' => false, 'freshness' => false ];
	$deferValues = [ false, DeferredUpdates::PRESEND, DeferredUpdates::POSTSEND ];
	if ( !in_array( $options['defer'], $deferValues, true ) ) {
	throw new InvalidArgumentException( 'Invalid value for defer: ' . $options['defer'] );
	}

	$triggeringUser = $this->options['triggeringUser'] ?? $this->user;
	[ $causeAction, $causeAgent ] = $this->getCauseForTracing();
	if ( isset( $options['known-revision-output'] ) ) {
	$this->getRenderedRevision()->setRevisionParserOutput( $options['known-revision-output'] );
	}

	// Bundle all of the data updates into a single deferred update wrapper so that
	// any failure will cause at most one refreshLinks job to be enqueued by
	// DeferredUpdates::doUpdates(). This is hard to do when there are many separate
	// updates that are not defined as being related.
	$update = new RefreshSecondaryDataUpdate(
	$this->loadbalancerFactory,
	// @phan-suppress-next-line PhanTypeMismatchArgumentNullable Already checked
	$triggeringUser,
	$this->wikiPage,
	$this->revision,
	$this,
	[ 'recursive' => $options['recursive'], 'freshness' => $options['freshness'] ]
	);
	$update->setCause( $causeAction, $causeAgent );

	if ( $options['defer'] === false ) {
	DeferredUpdates::attemptUpdate( $update );
	} else {
	DeferredUpdates::addUpdate( $update, $options['defer'] );
	}
	}

	/**
	* Causes parser cache entries to be updated.
	*
	* @note This does not update links tables. Use doSecondaryDataUpdates() for that.
	* @note Application logic should use Wikipage::updateParserCache instead.
	*/
	public function doParserCacheUpdate() {
	$this->assertHasRevision( __METHOD__ );

	$wikiPage = $this->getWikiPage(); // TODO: ParserCache should accept a RevisionRecord instead

	// NOTE: this may trigger the first parsing of the new content after an edit (when not
	// using pre-generated stashed output).
	// XXX: we may want to use the PoolCounter here. This would perhaps allow the initial parse
	// to be performed post-send. The client could already follow a HTTP redirect to the
	// page view, but would then have to wait for a response until rendering is complete.
	$output = $this->getCanonicalParserOutput();

	// Save it to the parser cache. Use the revision timestamp in the case of a
	// freshly saved edit, as that matches page_touched and a mismatch would trigger an
	// unnecessary reparse.
	$timestamp = $this->options['newrev'] ? $this->revision->getTimestamp()
	: $output->getCacheTime();
	$this->parserCache->save(
	$output, $wikiPage, $this->getCanonicalParserOptions(),
	$timestamp, $this->revision->getId()
	);

	// If we enable cache warming with parsoid outputs, let's do it at the same
	// time we're populating the parser cache with pre-generated HTML.
	// Use OPT_FORCE_PARSE to avoid a useless cache lookup.
	if ( $this->warmParsoidParserCache ) {
	$cacheWarmingParams = $this->getCauseForTracing();
	$cacheWarmingParams['options'] = ParserOutputAccess::OPT_FORCE_PARSE;

	$this->jobQueueGroup->lazyPush(
	ParsoidCachePrewarmJob::newSpec(
	$this->revision->getId(),
	$wikiPage->toPageRecord(),
	$cacheWarmingParams
	)
	);
	}
	}

	}

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