Merge "Show message fallback keys when using &uselang=qqx"

includes/language/Message.php

@@ -973,6 +973,11 @@ class Message implements MessageSpecifier, Serializable {
 			return '⧼' . htmlspecialchars( $this->key ) . '⧽';
 		}
 
+		# Replace $/ with a list of alternative message keys for &uselang=qqx.
+		if ( strpos( $string, '$/' ) !== false ) {
+			$keylist = implode( ' / ', $this->keysToTry );
+			$string = str_replace( '$/', $keylist, $string );
+		}
 		# Replace $* with a list of parameters for &uselang=qqx.
 		if ( strpos( $string, '$*' ) !== false ) {
 			$paramlist = '';

includes/languages/LanguageQqx.php

@@ -22,7 +22,8 @@
  */
 
 /**
- * For all translated messages, this returns the name of the message bracketed.
+ * For all translated messages, this returns a special value handled in Message::format()
+ * to display the message key (and fallback keys) and the parameters passed to the message.
  * This does not affect untranslated messages.
  *
  * NOTE: It returns a valid title, because there are some poorly written
@@ -36,6 +37,7 @@ class LanguageQqx extends Language {
 	 * @return string
 	 */
 	public function getMessage( $key ) {
-		return "($key$*)";
+		// Special values replaced in Message::format()
+		return '($/$*)';
 	}
 }

tests/phpunit/includes/MessageTest.php

@@ -836,6 +836,29 @@ class MessageTest extends MediaWikiLangTestCase {
 		);
 	}
 
+	/**
+	 * @covers Message::format
+	 * @covers LanguageQqx
+	 */
+	public function testQqxPlaceholders() {
+		$this->assertSame(
+			wfMessage( 'test' )->inLanguage( 'qqx' )->text(),
+			'(test)'
+		);
+		$this->assertSame(
+			wfMessage( 'test' )->params( 'a', 'b' )->inLanguage( 'qqx' )->text(),
+			'(test: a, b)'
+		);
+		$this->assertSame(
+			wfMessageFallback( 'test', 'other-test' )->inLanguage( 'qqx' )->text(),
+			'(test / other-test)'
+		);
+		$this->assertSame(
+			wfMessageFallback( 'test', 'other-test' )->params( 'a', 'b' )->inLanguage( 'qqx' )->text(),
+			'(test / other-test: a, b)'
+		);
+	}
+
 	/**
 	 * @covers Message::inContentLanguage
 	 */