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diff --git a/MLEB/Translate/src/Utilities/UnicodePlural.php b/MLEB/Translate/src/Utilities/UnicodePlural.php
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+++ b/MLEB/Translate/src/Utilities/UnicodePlural.php
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+<?php
+/**
+ * @file
+ * @license GPL-2.0-or-later
+ */
+
+namespace MediaWiki\Extensions\Translate\Utilities;
+
+use RuntimeException;
+use TranslateUtils;
+
+/**
+ * @since 2019.09
+ */
+class UnicodePlural {
+	private const PRE = '{{PLURAL|';
+	private const POST = '}}';
+
+	/**
+	 * Returns CLDR plural rule for given language.
+	 *
+	 * @param string $code Language tag in MediaWiki internal format.
+	 * @return array|null Empty string if no plural rule found
+	 */
+	public static function getPluralKeywords( $code ) {
+		$filePath = __DIR__ . '/../../data/plural-cldr.json';
+		$ruleData = json_decode( file_get_contents( $filePath ), true );
+
+		$ruleSet = $ruleData[ 'supplemental' ][ 'plurals-type-cardinal' ][ $code ] ?? null;
+		if ( $ruleSet === null ) {
+			return null;
+		}
+
+		$keywords = [];
+		foreach ( array_keys( $ruleSet ) as $name ) {
+			$keywords[] = str_replace( 'pluralRule-count-', '', $name );
+		}
+
+		return $keywords;
+	}
+
+	/**
+	 * Quick way to check if the text contains plural syntax.
+	 *
+	 * @param string $text
+	 * @return bool
+	 */
+	public static function hasPlural( $text ) {
+		return strpos( $text, self::PRE ) !== false;
+	}
+
+	/**
+	 * Format plural forms map as single string suitable for translation.
+	 *
+	 * This does not check validity of forms. Use ::convertFormListToFormMap for that.
+	 * @param string[] $forms
+	 * @return string
+	 */
+	public static function flattenMap( array $forms ) {
+		$list = [];
+		foreach ( $forms as $keyword => $value ) {
+			$list[] = [ $keyword, $value ];
+		}
+
+		return self::flattenList( $list );
+	}
+
+	/**
+	 * Format plural forms list as single string.
+	 *
+	 * This does not check validity of forms.
+	 * @param array[] $formList [ keyword, form ] pairs.
+	 * @return string
+	 */
+	public static function flattenList( array $formList ) {
+		$formatted = [];
+		foreach ( $formList as list( $keyword, $value ) ) {
+			$formatted[] = self::formatForm( $keyword, $value );
+		}
+
+		return self::PRE . implode( '|', $formatted ) . self::POST;
+	}
+
+	private static function formatForm( $keyword, $value ) {
+		$prefix = $keyword === 'other' ? '' : "$keyword=";
+		return $prefix . $value;
+	}
+
+	/**
+	 * Format translation with plural forms as array of forms.
+	 *
+	 * Reverse of flatten. Do note that A may be != flatten( unflatten( A ) ) because
+	 * translators can place part of the text outside the plural markup or use multiple
+	 * instances of the markup.
+	 *
+	 * @param string $text
+	 * @param string[] $expectedKeywords
+	 * @return string[]
+	 */
+	public static function unflatten( $text, $expectedKeywords ) {
+		list( $template, $instanceMap ) = self::parsePluralForms( $text );
+		return self::expandTemplate( $template, $instanceMap, $expectedKeywords );
+	}
+
+	/**
+	 * Parses plural markup into a structure form.
+	 *
+	 * @param string $text
+	 * @return array [ string $template, array $instanceMap ]
+	 */
+	public static function parsePluralForms( $text ) {
+		$m = [];
+		$pre = preg_quote( self::PRE, '/' );
+		$post = preg_quote( self::POST, '/' );
+
+		$ok = preg_match_all( "/$pre(.*)$post/Us", $text, $m );
+		if ( $ok === false ) {
+			throw new RuntimeException( "Plural regular expression failed for text: $text" );
+		}
+
+		$template = $text;
+		$instanceMap = [];
+
+		foreach ( $m[0] as $instanceIndex => $instanceText ) {
+			$ph = TranslateUtils::getPlaceholder();
+
+			// Using preg_replace instead of str_replace because of the limit parameter
+			$pattern = '/' . preg_quote( $instanceText, '/' ) . '/';
+			$template = preg_replace( $pattern, $ph, $template, 1 );
+
+			$instanceForms = [];
+			foreach ( explode( '|', $m[ 1 ][ $instanceIndex ] ) as $form ) {
+				$m2 = [];
+				$ok = preg_match( "~\s*([a-z]+)\s*=(.+)~s", $form, $m2 );
+				$keyword = $ok ? $m2[ 1 ] : 'other';
+				$value = $ok ? trim( $m2[ 2 ] ) : $form;
+				$instanceForms[] = [ $keyword, $value ];
+			}
+
+			$instanceMap[$ph] = $instanceForms;
+		}
+
+		return [ $template, $instanceMap ];
+	}
+
+	/**
+	 * Gives fully expanded forms given a template and parsed plural markup instances.
+	 *
+	 * @param string $template
+	 * @param array $instanceMap
+	 * @param string[] $expectedKeywords
+	 * @return string[]
+	 */
+	public static function expandTemplate( $template, array $instanceMap, $expectedKeywords ) {
+		$formArray = [];
+
+		// Convert from list of forms to map of forms for easier processing
+		foreach ( $instanceMap as $ph => $list ) {
+			$instanceMap[ $ph ] = self::convertFormListToFormMap( $list, $expectedKeywords );
+		}
+
+		foreach ( $expectedKeywords as $keyword ) {
+			// Start with the whole string
+			$form = $template;
+
+			// Loop over each plural markup instance and replace it with the plural form belonging
+			// to the current index
+			foreach ( $instanceMap as $ph => $instanceFormMap ) {
+				// For missing forms, fall back to empty text.
+				$replacement = $instanceFormMap[ $keyword ] ?? '';
+				$form = str_replace( $ph, $replacement, $form );
+			}
+
+			$formArray[ $keyword ] = $form;
+		}
+
+		return $formArray;
+	}
+
+	public static function convertFormListToFormMap( array $formList, array $expectedKeywords ) {
+		$formMap = [];
+		foreach ( $formList as list( $keyword, $value ) ) {
+			$formMap[ $keyword ] = $value;
+		}
+
+		$sortedFormMap = [];
+		foreach ( $expectedKeywords as $keyword ) {
+			$sortedFormMap[ $keyword ] = $formMap[ $keyword ] ?? null;
+		}
+
+		return $sortedFormMap;
+	}
+}