Split MessageParser out of MessageCache

MessageCache has enough to do without also being a parser. Split a
MessageParser class out of MessageCache and make it a service.

* MessageCache::parseWithPostprocessing() becomes MessageParser::parse()
  because every caller wants postprocessing so it makes sense to use the
  shorter name for this.
* MessageCache::parse() becomes MessageParser
  ::parseWithoutPostprocessing(). I changed the return type from
  ParserOutput|string to ParserOutput, which is a followup to
  I8a1fa84e650d920d07d74722d8059d5afeedec6b. Narrowing the return type
  does not break b/c so it is possible to make this change for both
  variants.
* In the new methods, a null title is always a convenience alias for a
  placeholder title (Special:Badtitle). This reflects the convention in
  Parser::setPage(). The old MessageCache::parse() retains its b/c
  fallback to $wgTitle. MessageCache::transform() had the potential to
  fall back to the title used in the previous call, a fragile mechanism
  which I removed without deprecation.
* For consistency, allow a string language in all new methods.
* In EmailNotification, clean up an early attempt at global state
  avoidance.

Change-Id: I05ab21508d5f8394189fd41ac6a2254ac0e0d785

8 files changed, 132 insertions, 30 deletions

diff --git a/tests/phpunit/includes/Status/StatusFormatterTest.php b/tests/phpunit/includes/Status/StatusFormatterTest.php
index b16d8064b2a9..289c9c381d41 100644
--- a/tests/phpunit/includes/Status/StatusFormatterTest.php
+++ b/tests/phpunit/includes/Status/StatusFormatterTest.php
@@ -1,6 +1,7 @@
 <?php
 
 use MediaWiki\Context\RequestContext;
+use MediaWiki\Language\MessageParser;
 use MediaWiki\Language\RawMessage;
 use MediaWiki\Message\Message;
 use MediaWiki\Parser\ParserOutput;
@@ -37,8 +38,8 @@ class StatusFormatterTest extends MediaWikiLangTestCase {
 			}
 		};
 
-		$cache = $this->createNoOpMock( MessageCache::class, [ 'parseWithPostprocessing' ] );
-		$cache->method( 'parseWithPostprocessing' )->willReturnCallback(
+		$cache = $this->createNoOpMock( MessageParser::class, [ 'parse' ] );
+		$cache->method( 'parse' )->willReturnCallback(
 			static function ( $text, ...$args ) {
 				$text = html_entity_decode( $text, ENT_QUOTES | ENT_HTML5 );
 				return new ParserOutput( "<p>" . trim( $text ) . "\n</p>" );
diff --git a/tests/phpunit/includes/language/LocalizationUpdateSpyTrait.php b/tests/phpunit/includes/language/LocalizationUpdateSpyTrait.php
index 0a7aaed1b054..05b3d037f2a1 100644
--- a/tests/phpunit/includes/language/LocalizationUpdateSpyTrait.php
+++ b/tests/phpunit/includes/language/LocalizationUpdateSpyTrait.php
@@ -41,9 +41,6 @@ trait LocalizationUpdateSpyTrait {
 		$messageCache->method( 'get' )
 			->willReturn( 'dummy test' );
 
-		$messageCache->method( 'transform' )
-			->willReturn( 'dummy test' );
-
 		$messageCache->method( 'getMsgFromNamespace' )
 			->willReturn( false );
 
diff --git a/tests/phpunit/includes/language/MessageCacheTest.php b/tests/phpunit/includes/language/MessageCacheTest.php
index 05278ed02d15..731915a20e8c 100644
--- a/tests/phpunit/includes/language/MessageCacheTest.php
+++ b/tests/phpunit/includes/language/MessageCacheTest.php
@@ -3,9 +3,7 @@
 use MediaWiki\CommentStore\CommentStoreComment;
 use MediaWiki\Content\ContentHandler;
 use MediaWiki\Deferred\DeferredUpdates;
-use MediaWiki\Language\RawMessage;
 use MediaWiki\MainConfigNames;
-use MediaWiki\Page\PageIdentityValue;
 use MediaWiki\Revision\RevisionRecord;
 use MediaWiki\Revision\SlotRecord;
 use MediaWiki\Title\Title;
@@ -332,21 +330,6 @@ class MessageCacheTest extends MediaWikiLangTestCase {
 		];
 	}
 
-	public function testNestedMessageParse() {
-		$msgOuter = ( new RawMessage( '[[Link|{{#language:}}]]' ) )
-			->inLanguage( 'outer' )
-			->page( new PageIdentityValue( 1, NS_MAIN, 'Link', PageIdentityValue::LOCAL ) );
-
-		// T372891: Allow nested message parsing
-		// Any hook from Linker or LinkRenderer will do for this test, but this one is the simplest
-		$this->setTemporaryHook( 'SelfLinkBegin', static function ( $nt, &$html, &$trail, &$prefix, &$ret ) {
-			$msgInner = ( new RawMessage( '{{#language:}}' ) )->inLanguage( 'inner' );
-			$html .= $msgInner->escaped();
-		} );
-
-		$this->assertEquals( '<a class="mw-selflink selflink">outerinner</a>', $msgOuter->parse() );
-	}
-
 	/** @dataProvider provideXssLanguage */
 	public function testXssLanguage( array $config, bool $expectXssMessage ): void {
 		$this->overrideConfigValues( $config + [
diff --git a/tests/phpunit/includes/language/MessageParserTest.php b/tests/phpunit/includes/language/MessageParserTest.php
new file mode 100644
index 000000000000..eeb980598e0d
--- /dev/null
+++ b/tests/phpunit/includes/language/MessageParserTest.php
@@ -0,0 +1,120 @@
+<?php
+
+use MediaWiki\DAO\WikiAwareEntity;
+use MediaWiki\Language\RawMessage;
+use MediaWiki\Page\PageIdentityValue;
+
+/**
+ * @covers MediaWiki\Language\MessageParser
+ */
+class MessageParserTest extends MediaWikiIntegrationTestCase {
+
+	public function testNestedMessageParse() {
+		$msgOuter = ( new RawMessage( '[[Link|{{#language:}}]]' ) )
+			->inLanguage( 'outer' )
+			->page( new PageIdentityValue( 1, NS_MAIN, 'Link', PageIdentityValue::LOCAL ) );
+
+		// T372891: Allow nested message parsing
+		// Any hook from Linker or LinkRenderer will do for this test, but this one is the simplest
+		$this->setTemporaryHook( 'SelfLinkBegin', static function ( $nt, &$html, &$trail, &$prefix, &$ret ) {
+			$msgInner = ( new RawMessage( '{{#language:}}' ) )->inLanguage( 'inner' );
+			$html .= $msgInner->escaped();
+		} );
+
+		$this->assertEquals( '<a class="mw-selflink selflink">outerinner</a>', $msgOuter->parse() );
+	}
+
+	public static function provideTransform() {
+		return [
+			[
+				'test',
+				[],
+				'test'
+			],
+			[
+				'{{PLURAL:21|one|more}}',
+				[ 'lang' => 'en' ],
+				'more'
+			],
+			[
+				'{{PLURAL:21|one|more}}',
+				[ 'lang' => 'be' ],
+				'one'
+			],
+			[
+				'{{PAGENAME}}',
+				[],
+				'Badtitle/MessageParser'
+			],
+			[
+				'{{PAGENAME}}',
+				[ 'page' => 'Main_Page' ],
+				'Main Page',
+			]
+		];
+	}
+
+	/**
+	 * @dataProvider provideTransform
+	 */
+	public function testTransform( $input, $options, $expected ) {
+		$messageParser = $this->getServiceContainer()->getMessageParser();
+		$result = $messageParser->transform(
+			$input,
+			$options['interface'] ?? true,
+			$options['lang'] ?? null,
+			$this->makePage( $options['page'] ?? null )
+		);
+		$this->assertSame( $expected, $result );
+	}
+
+	private function makePage( $title ) {
+		return $title
+			? new PageIdentityValue( 1, NS_MAIN, $title, WikiAwareEntity::LOCAL )
+			: null;
+	}
+
+	public static function provideParse() {
+		return [
+			[
+				'test',
+				[],
+				'test'
+			],
+			[
+				'* Bullet',
+				[],
+				'<ul><li>Bullet</li></ul>'
+			],
+			[
+				'* Asterisk',
+				[ 'lineStart' => false ],
+				'* Asterisk'
+			],
+			[
+				'{{#bcp47:}}',
+				[ 'lang' => 'fr' ],
+				'fr'
+			],
+		];
+	}
+
+	/**
+	 * @dataProvider provideParse
+	 * @param string $input
+	 * @param array $options
+	 * @param string $expected
+	 */
+	public function testParse( $input, $options, $expected ) {
+		$messageParser = $this->getServiceContainer()->getMessageParser();
+		$parserOutput = $messageParser->parse(
+			$input,
+			$this->makePage( $options['page'] ?? null ),
+			$options['lineStart'] ?? true,
+			$options['interface'] ?? true,
+			$options['lang'] ?? null
+		);
+		$result = Parser::stripOuterParagraph( $parserOutput->getContentHolderText() );
+		$this->assertSame( $expected, $result );
+	}
+}
diff --git a/tests/phpunit/includes/specials/SpecialRecentChangesTest.php b/tests/phpunit/includes/specials/SpecialRecentChangesTest.php
index a7a2d530afc0..f50984c67513 100644
--- a/tests/phpunit/includes/specials/SpecialRecentChangesTest.php
+++ b/tests/phpunit/includes/specials/SpecialRecentChangesTest.php
@@ -1,6 +1,7 @@
 <?php
 
 use MediaWiki\Context\RequestContext;
+use MediaWiki\Language\MessageParser;
 use MediaWiki\MainConfigNames;
 use MediaWiki\Request\FauxRequest;
 use MediaWiki\Specials\SpecialRecentChanges;
@@ -26,7 +27,7 @@ class SpecialRecentChangesTest extends AbstractChangesListSpecialPageTestCase {
 	protected function getPage(): SpecialRecentChanges {
 		return new SpecialRecentChanges(
 			$this->getServiceContainer()->getWatchedItemStore(),
-			$this->getServiceContainer()->getMessageCache(),
+			$this->getServiceContainer()->getMessageParser(),
 			$this->getServiceContainer()->getUserOptionsLookup(),
 			$this->getServiceContainer()->getChangeTagsStore(),
 			$this->getServiceContainer()->getUserIdentityUtils(),
@@ -258,7 +259,7 @@ class SpecialRecentChangesTest extends AbstractChangesListSpecialPageTestCase {
 		$page = new class (
 			$dense,
 			$this->getServiceContainer()->getWatchedItemStore(),
-			$this->getServiceContainer()->getMessageCache(),
+			$this->getServiceContainer()->getMessageParser(),
 			$this->getServiceContainer()->getUserOptionsLookup()
 		)  extends SpecialRecentChanges {
 			private $dense;
@@ -266,10 +267,10 @@ class SpecialRecentChangesTest extends AbstractChangesListSpecialPageTestCase {
 			public function __construct(
 				$dense,
 				?WatchedItemStoreInterface $watchedItemStore = null,
-				?MessageCache $messageCache = null,
+				?MessageParser $messageParser = null,
 				?\MediaWiki\User\Options\UserOptionsLookup $userOptionsLookup = null
 			) {
-				parent::__construct( $watchedItemStore, $messageCache, $userOptionsLookup );
+				parent::__construct( $watchedItemStore, $messageParser, $userOptionsLookup );
 				$this->dense = $dense;
 			}
 
diff --git a/tests/phpunit/includes/title/TitleTest.php b/tests/phpunit/includes/title/TitleTest.php
index 81e1e17ab2d4..0b66ab0f37d9 100644
--- a/tests/phpunit/includes/title/TitleTest.php
+++ b/tests/phpunit/includes/title/TitleTest.php
@@ -1798,7 +1798,6 @@ class TitleTest extends MediaWikiIntegrationTestCase {
 	public function testNewMainPage() {
 		$mock = $this->createMock( MessageCache::class );
 		$mock->method( 'get' )->willReturn( 'Foresheet' );
-		$mock->method( 'transform' )->willReturn( 'Foresheet' );
 
 		$this->setService( 'MessageCache', $mock );
 
@@ -1816,7 +1815,6 @@ class TitleTest extends MediaWikiIntegrationTestCase {
 	public function testNewMainPageNoRecursion() {
 		$mock = $this->createMock( MessageCache::class );
 		$mock->method( 'get' )->willReturn( 'localtestiw:' );
-		$mock->method( 'transform' )->willReturn( 'localtestiw:' );
 		$this->setService( 'MessageCache', $mock );
 
 		$this->assertSame(
diff --git a/tests/phpunit/unit/includes/Permissions/UserAuthorityTest.php b/tests/phpunit/unit/includes/Permissions/UserAuthorityTest.php
index 9d0833bb8b9e..45e521ac786f 100644
--- a/tests/phpunit/unit/includes/Permissions/UserAuthorityTest.php
+++ b/tests/phpunit/unit/includes/Permissions/UserAuthorityTest.php
@@ -22,6 +22,7 @@ namespace MediaWiki\Tests\Unit\Permissions;
 
 use InvalidArgumentException;
 use MediaWiki\Block\AbstractBlock;
+use MediaWiki\Language\MessageParser;
 use MediaWiki\Page\PageIdentity;
 use MediaWiki\Page\PageIdentityValue;
 use MediaWiki\Permissions\PermissionStatus;
@@ -386,7 +387,7 @@ class UserAuthorityTest extends MediaWikiUnitTestCase {
 
 		$formatter = new StatusFormatter(
 			new FakeQqxMessageLocalizer(),
-			$this->createNoOpMock( \MessageCache::class ),
+			$this->createNoOpMock( MessageParser::class ),
 			new NullLogger()
 		);
 		// Despite all the futzing around with services, StatusFormatter depends on this global through wfEscapeWikiText
diff --git a/tests/phpunit/unit/includes/language/FormatterFactoryTest.php b/tests/phpunit/unit/includes/language/FormatterFactoryTest.php
index 49d1c43dd4bb..834582168cf3 100644
--- a/tests/phpunit/unit/includes/language/FormatterFactoryTest.php
+++ b/tests/phpunit/unit/includes/language/FormatterFactoryTest.php
@@ -3,6 +3,7 @@
 use MediaWiki\Context\IContextSource;
 use MediaWiki\HookContainer\HookContainer;
 use MediaWiki\Language\FormatterFactory;
+use MediaWiki\Language\MessageParser;
 use MediaWiki\Languages\LanguageFactory;
 use MediaWiki\Title\TitleFormatter;
 use MediaWiki\User\UserIdentityUtils;
@@ -15,7 +16,7 @@ class FormatterFactoryTest extends MediaWikiUnitTestCase {
 
 	private function getFactory() {
 		return new FormatterFactory(
-			$this->createNoOpMock( MessageCache::class ),
+			$this->createNoOpMock( MessageParser::class ),
 			$this->createNoOpMock( TitleFormatter::class ),
 			$this->createNoOpMock( HookContainer::class ),
 			$this->createNoOpMock( UserIdentityUtils::class ),