From f7bb180fef88665866ef3922e596edbf273ce78d Mon Sep 17 00:00:00 2001
From: "C. Scott Ananian" <cscott@cscott.net>
Date: Fri, 13 Jul 2018 15:40:20 -0400
Subject: [PATCH] Accept BCP 47 codes in LanguageConverter rules

Facilitate a gradual migration away from non-standard MediaWiki language
codes.  This will ensure that (a) rules can be written with standard
BCP 47 codes, and (b) rules written with existing nonstandard codes will
continue to work once these are added to
LanguageCode::$deprecatedLanguageCodeMapping.

Change-Id: I3ba96faafaf40bd47fb5919621f7035f0431a698
---
 languages/ConverterRule.php     | 20 +++++++++++---------
 languages/LanguageConverter.php | 15 ++++++++++++++-
 tests/parser/parserTests.txt    | 13 +++++++++++++
 3 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/languages/ConverterRule.php b/languages/ConverterRule.php
index dc61519c69..6ce1274be3 100644
--- a/languages/ConverterRule.php
+++ b/languages/ConverterRule.php
@@ -153,25 +153,27 @@ class ConverterRule {
 			$to = trim( $v[1] );
 			$v = trim( $v[0] );
 			$u = explode( '=>', $v, 2 );
+			$vv = $this->mConverter->validateVariant( $v );
 			// if $to is empty (which is also used as $from in bidtable),
 			// strtr() could return a wrong result.
-			if ( count( $u ) == 1 && $to !== '' && in_array( $v, $variants ) ) {
-				$bidtable[$v] = $to;
+			if ( count( $u ) == 1 && $to !== '' && $vv ) {
+				$bidtable[$vv] = $to;
 			} elseif ( count( $u ) == 2 ) {
 				$from = trim( $u[0] );
 				$v = trim( $u[1] );
+				$vv = $this->mConverter->validateVariant( $v );
 				// if $from is empty, strtr() could return a wrong result.
-				if ( array_key_exists( $v, $unidtable )
-					&& !is_array( $unidtable[$v] )
+				if ( array_key_exists( $vv, $unidtable )
+					&& !is_array( $unidtable[$vv] )
 					&& $from !== ''
-					&& in_array( $v, $variants ) ) {
-					$unidtable[$v] = [ $from => $to ];
-				} elseif ( $from !== '' && in_array( $v, $variants ) ) {
-					$unidtable[$v][$from] = $to;
+					&& $vv ) {
+					$unidtable[$vv] = [ $from => $to ];
+				} elseif ( $from !== '' && $vv ) {
+					$unidtable[$vv][$from] = $to;
 				}
 			}
 			// syntax error, pass
-			if ( !isset( $this->mConverter->mVariantNames[$v] ) ) {
+			if ( !isset( $this->mConverter->mVariantNames[$vv] ) ) {
 				$bidtable = [];
 				$unidtable = [];
 				break;
diff --git a/languages/LanguageConverter.php b/languages/LanguageConverter.php
index ea26c64dc7..137fe87d1e 100644
--- a/languages/LanguageConverter.php
+++ b/languages/LanguageConverter.php
@@ -1175,8 +1175,21 @@ class LanguageConverter {
 			//    [1] => 'zh-hant:<span style="font-size:120%;">yyy</span>'
 			//    [2] => ''
 			//  ]
-			$pat = '/;\s*(?=';
+			$expandedVariants = [];
 			foreach ( $this->mVariants as $variant ) {
+				$expandedVariants[ $variant ] = 1;
+				// Accept standard BCP 47 names for variants as well.
+				$expandedVariants[ LanguageCode::bcp47( $variant ) ] = 1;
+			}
+			// Accept old deprecated names for variants
+			foreach ( LanguageCode::getDeprecatedCodeMapping() as $old => $new ) {
+				if ( isset( $expandedVariants[ $new ] ) ) {
+					$expandedVariants[ $old ] = 1;
+				}
+			}
+
+			$pat = '/;\s*(?=';
+			foreach ( $expandedVariants as $variant => $ignore ) {
 				// zh-hans:xxx;zh-hant:yyy
 				$pat .= $variant . '\s*:|';
 				// xxx=>zh-hans:yyy; xxx=>zh-hant:zzz
diff --git a/tests/parser/parserTests.txt b/tests/parser/parserTests.txt
index bbd9ecbe99..50c6a891b9 100644
--- a/tests/parser/parserTests.txt
+++ b/tests/parser/parserTests.txt
@@ -22434,6 +22434,19 @@ language=zh variant=zh-tw
 <p><span typeof="mw:LanguageVariant" data-parsoid='{"tSp":[6]}' data-mw-variant='{"twoway":[{"l":"zh","t":"China"},{"l":"zh-tw","t":"Taiwan"}]}'></span>, not China</p>
 !! end
 
+!! test
+Explicit definition of language variant alternatives (BCP 47 codes)
+!! options
+language=zh variant=zh-tw
+!! wikitext
+-{zh:China;zh-Hant-TW:Taiwan}-, not China
+!! html/php
+<p>Taiwan, not China
+</p>
+!! html/parsoid
+<p><span typeof="mw:LanguageVariant" data-parsoid='{"tSp":[6]}' data-mw-variant='{"twoway":[{"l":"zh","t":"China"},{"l":"zh-Hant-TW","t":"Taiwan"}]}'></span>, not China</p>
+!! end
+
 !! test
 Filter syntax for language variants
 !! options
-- 
2.20.1