Parameterize ChangeTags::buildTagFilterSelector to support various tag sets

Why:
`ChangeTags::buildTagFilterSelector` is an opinionated chain of calls
that results in the markup for a select input with specific tag options
(explicitly and software defined tags that have hits). In order to
support customization to the `HTMLTagFilter` widget, add support for
parameters.

These parameters will support filtering for active-only tags or not
and choosing between all on-wiki tags or software-defined tags only.

What:
- Support an `activeOnly` parameter, which will either show all defined
  tags or only tags that have hits (active)
  + For legibility, add `TAG_SET_ACTIVE_ONLY` and `TAG_SET_ALL` constants
    to support this parameter
- Support a `useAllTags` parameter, which if true will use all tags
  and if which false will only use software-defined tags
  + For legibility, add `USE_ALL_TAGS` and `USE_SOFTWARE_TAGS_ONLY`
    constants to support this parameter

Bug: T378622
Change-Id: Ib6ba27944cdf22bdb05dbfd34b2e5f8727261da7

includes/changetags/ChangeTags.php

@@ -139,6 +139,29 @@ class ChangeTags {
 
 	public const DISPLAY_TABLE_ALIAS = 'changetagdisplay';
 
+	/**
+	 * Constants that can be used to set the `activeOnly` parameter for calling
+	 * self::buildCustomTagFilterSelect in order to improve function/parameter legibility
+	 *
+	 * If TAG_SET_ACTIVE_ONLY is used then the hit count for each tag will be checked against
+	 * and only tags with hits will be returned
+	 * Otherwise if TAG_SET_ALL is used then all tags will be returned regardlesss of if they've
+	 * ever been used or not
+	 */
+	public const TAG_SET_ACTIVE_ONLY = true;
+	public const TAG_SET_ALL = false;
+
+	/**
+	 * Constants that can be used to set the `useAllTags` parameter for calling
+	 * self::buildCustomTagFilterSelect in order to improve function/parameter legibility
+	 *
+	 * If USE_ALL_TAGS is used then all on-wiki tags will be returned
+	 * Otherwise if USE_SOFTWARE_TAGS_ONLY is used then only mediawiki core-defined tags
+	 * will be returned
+	 */
+	public const USE_ALL_TAGS = true;
+	public const USE_SOFTWARE_TAGS_ONLY = false;
+
 	/**
 	 * Loads defined core tags, checks for invalid types (if not array),
 	 * and filters for supported and enabled (if $all is false) tags only.
@@ -717,7 +740,8 @@ class ChangeTags {
 	}
 
 	/**
-	 * Build a text box to select a change tag
+	 * Build a text box to select a change tag. The tag set can be customized via the $activeOnly
+	 * and $useAllTags parameters and defaults to all active tags.
 	 *
 	 * @param string $selected Tag to select by default
 	 * @param bool $ooui Use an OOUI TextInputWidget as selector instead of a non-OOUI input field
@@ -725,10 +749,15 @@ class ChangeTags {
 	 * @param IContextSource|null $context
 	 * @note Even though it takes null as a valid argument, an IContextSource is preferred
 	 *       in a new code, as the null value can change in the future
+	 * @param bool $activeOnly Whether to filter for tags that have been used or not
+	 * @param bool $useAllTags Whether to use all known tags or to only use software defined tags
+	 *        These map to ChangeTagsStore->listDefinedTags and ChangeTagsStore->getSoftwareTags respectively
 	 * @return array an array of (label, selector)
 	 */
 	public static function buildTagFilterSelector(
-		$selected = '', $ooui = false, ?IContextSource $context = null
+		$selected = '', $ooui = false, ?IContextSource $context = null,
+		bool $activeOnly = self::TAG_SET_ACTIVE_ONLY,
+		bool $useAllTags = self::USE_ALL_TAGS
 	) {
 		if ( !$context ) {
 			$context = RequestContext::getMain();
@@ -741,7 +770,13 @@ class ChangeTags {
 			return [];
 		}
 
-		$tags = self::getChangeTagList( $context, $context->getLanguage() );
+		$tags = self::getChangeTagList(
+			$context,
+			$context->getLanguage(),
+			$activeOnly,
+			$useAllTags
+		);
+
 		$autocomplete = [];
 		foreach ( $tags as $tagInfo ) {
 			$autocomplete[ $tagInfo['label'] ] = $tagInfo['name'];
@@ -1259,6 +1294,7 @@ class ChangeTags {
 
 	/**
 	 * Get information about change tags, without parsing messages, for tag filter dropdown menus.
+	 * By default, this will return explicitly-defined and software-defined tags that are currently active (have hits)
 	 *
 	 * Message contents are the raw values (->plain()), because parsing messages is expensive.
 	 * Even though we're not parsing messages, building a data structure with the contents of
@@ -1280,24 +1316,49 @@ class ChangeTags {
 	 *
 	 * @param MessageLocalizer $localizer
 	 * @param Language $lang
+	 * @param bool $activeOnly
+	 * @param bool $useAllTags
 	 * @return array[] Information about each tag
 	 */
-	public static function getChangeTagListSummary( MessageLocalizer $localizer, Language $lang ) {
+	public static function getChangeTagListSummary(
+		MessageLocalizer $localizer,
+		Language $lang,
+		bool $activeOnly = self::TAG_SET_ACTIVE_ONLY,
+		bool $useAllTags = self::USE_ALL_TAGS
+	) {
+		$changeTagStore = MediaWikiServices::getInstance()->getChangeTagsStore();
+
+		if ( $useAllTags ) {
+			$tagKeys = $changeTagStore->listDefinedTags();
+			$cacheKey = 'tags-list-summary';
+		} else {
+			$tagKeys = $changeTagStore->getSoftwareTags( true );
+			$cacheKey = 'core-software-tags-summary';
+		}
+
+		// if $tagHitCounts exists, check against it later to determine whether or not to omit tags
+		$tagHitCounts = null;
+		if ( $activeOnly ) {
+			$tagHitCounts = $changeTagStore->tagUsageStatistics();
+		} else {
+			// The full set of tags should use a different cache key than the subset
+			$cacheKey .= '-all';
+		}
+
 		$cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
 		return $cache->getWithSetCallback(
-			$cache->makeKey( 'tags-list-summary', $lang->getCode() ),
+			$cache->makeKey( $cacheKey, $lang->getCode() ),
 			WANObjectCache::TTL_DAY,
-			static function ( $oldValue, &$ttl, array &$setOpts ) use ( $localizer ) {
+			static function ( $oldValue, &$ttl, array &$setOpts ) use ( $localizer, $tagKeys, $tagHitCounts ) {
-				$changeTagStore = MediaWikiServices::getInstance()->getChangeTagsStore();
-				$tagHitCounts = $changeTagStore->tagUsageStatistics();
-
 				$result = [];
-				// Only list tags that are still actively defined
+				foreach ( $tagKeys as $tagName ) {
-				foreach ( $changeTagStore->listDefinedTags() as $tagName ) {
+					// Only list tags that are still actively defined
-					// Only list tags with more than 0 hits
+					if ( $tagHitCounts !== null ) {
-					$hits = $tagHitCounts[$tagName] ?? 0;
+						// Only list tags with more than 0 hits
-					if ( $hits <= 0 ) {
+						$hits = $tagHitCounts[$tagName] ?? 0;
-						continue;
+						if ( $hits <= 0 ) {
+							continue;
+						}
 					}
 
 					$labelMsg = self::tagShortDescriptionMessage( $tagName, $localizer );
@@ -1329,10 +1390,16 @@ class ChangeTags {
 	 *
 	 * @param MessageLocalizer $localizer
 	 * @param Language $lang
+	 * @param bool $activeOnly
+	 * @param bool $useAllTags
 	 * @return array[] Same as getChangeTagListSummary(), with messages parsed, stripped and truncated
 	 */
-	public static function getChangeTagList( MessageLocalizer $localizer, Language $lang ) {
+	public static function getChangeTagList(
-		$tags = self::getChangeTagListSummary( $localizer, $lang );
+		MessageLocalizer $localizer, Language $lang,
+		bool $activeOnly = self::TAG_SET_ACTIVE_ONLY, bool $useAllTags = self::USE_ALL_TAGS
+	) {
+		$tags = self::getChangeTagListSummary( $localizer, $lang, $activeOnly, $useAllTags );
+
 		foreach ( $tags as &$tagInfo ) {
 			if ( $tagInfo['labelMsg'] ) {
 				// Use localizer with the correct page title to parse plain message from the cache.

tests/phpunit/includes/changetags/ChangeTagsTest.php

@@ -2,6 +2,7 @@
 
 use MediaWiki\Language\RawMessage;
 use MediaWiki\MainConfigNames;
+use MediaWiki\MediaWikiServices;
 use Wikimedia\Rdbms\Platform\ISQLPlatform;
 
 /**
@@ -28,6 +29,97 @@ class ChangeTagsTest extends MediaWikiIntegrationTestCase {
 
 	// TODO most methods are not tested
 
+	public function testBuildTagFilterSelector_allTags() {
+		// Set `activeOnly` to false
+		// Expect that at least all the software defined tags are returned
+		$allTags = MediaWikiServices::getInstance()->getChangeTagsStore()->listDefinedTags();
+		$allTagsList = ChangeTags::getChangeTagListSummary(
+			RequestContext::getMain(),
+			RequestContext::getMain()->getLanguage(),
+			ChangeTags::TAG_SET_ALL
+		);
+		$this->assertTrue(
+			count( $allTagsList ) >= count( $allTags ),
+			'`activeOnly` is false, expect all software tags'
+		);
+	}
+
+	public function testBuildTagFilterSelector_allSoftwareTags() {
+		// Set both `activeOnly` and `useAllTags` to false
+		// Expect that only software defined tags are returned
+		$allSoftwareTags = MediaWikiServices::getInstance()->getChangeTagsStore()->getSoftwareTags( true );
+		$allSoftwareTagsList = ChangeTags::getChangeTagListSummary(
+			RequestContext::getMain(),
+			RequestContext::getMain()->getLanguage(),
+			ChangeTags::TAG_SET_ALL,
+			ChangeTags::USE_SOFTWARE_TAGS_ONLY
+		);
+		$this->assertTrue(
+			count( $allSoftwareTagsList ) == count( $allSoftwareTags ),
+			'`activeOnly` and `useAllTags` are false, expect only software tags'
+		);
+	}
+
+	public function testBuildTagFilterSelector_activeOnlyNoHits() {
+		// Enable and test `activeOnly` and expect no tags returned,
+		// as there are currently no tagged edits in the test database
+		$emptyTagListSummary = ChangeTags::getChangeTagListSummary(
+			RequestContext::getMain(),
+			RequestContext::getMain()->getLanguage(),
+			ChangeTags::TAG_SET_ACTIVE_ONLY
+		);
+		$this->assertCount( 0, $emptyTagListSummary, '`activeOnly` is true and no hits, expect no tags' );
+
+		// Assert that by default, an empty select is returned, as no tags have been used yet
+		$this->assertEquals(
+			[
+				'<label for="tagfilter"><a href="/wiki/Special:Tags" title="Special:Tags">Tag</a> filter:</label>',
+				'<input class="mw-tagfilter-input mw-ui-input mw-ui-input-inline" size="20" id="tagfilter" list="tagfilter-datalist" name="tagfilter"><datalist id="tagfilter-datalist"></datalist>'
+			],
+			ChangeTags::buildTagFilterSelector(
+				'', false, RequestContext::getMain()
+			)
+		);
+	}
+
+	public function testBuildTagFilterSelector_activeOnly() {
+		// Disable patrolling so reverts will happen without approval
+		$this->overrideConfigValues( [ MainConfigNames::UseRCPatrol => false ] );
+
+		// Make an edit and replace the content, adding the `mw-replace` tag to the revision
+		$page = $this->getExistingTestPage();
+		$this->editPage( $page, '1' );
+		$this->editPage(
+			$page, '0', '', NS_MAIN, $this->getTestUser()->getUser()
+		);
+
+		// Ensure all deferred updates are run
+		DeferredUpdates::doUpdates();
+
+		// Assert that only the `mw-replace` tag is returned
+		$replaceOnlyTagList = ChangeTags::getChangeTagListSummary(
+			RequestContext::getMain(),
+			RequestContext::getMain()->getLanguage()
+		);
+		$this->assertCount( 1, $replaceOnlyTagList, '`activeOnly` is true with 1 hit, return 1 tag' );
+		$this->assertEquals(
+			'mw-replace', $replaceOnlyTagList[0]['name'],
+			'`activeOnly` is true with 1 hit, return expected tag'
+		);
+
+		// Assert that the tag is reflected in the default markup returned
+		$this->assertEquals(
+			[
+				'<label for="tagfilter"><a href="/wiki/Special:Tags" title="Special:Tags">Tag</a> filter:</label>',
+				'<input class="mw-tagfilter-input mw-ui-input mw-ui-input-inline" size="20" id="tagfilter" list="tagfilter-datalist" name="tagfilter"><datalist id="tagfilter-datalist"><option value="mw-replace">Replaced</option></datalist>'
+			],
+			ChangeTags::buildTagFilterSelector(
+				'', false, RequestContext::getMain()
+			),
+			'`activeOnly` is true with 1 hit, return expected tag markup'
+		);
+	}
+
 	/** @dataProvider provideModifyDisplayQuery */
 	public function testModifyDisplayQuery(
 		$origQuery,