From 87070fc6743bfe5da7b49f07561fc1e0b03897c4 Mon Sep 17 00:00:00 2001
From: Brad Jorsch <bjorsch@wikimedia.org>
Date: Mon, 5 Jan 2015 11:59:48 -0500
Subject: [PATCH] API: Avoid unstubbing User for language pref when not needed

It's fairly common that the API doesn't need to load the user
preferences, except to implement the unfortunate default uselang=user.

So let's move the handling of uselang=user to
RequestContext::getLanguage(), and have the API just assume that its
parent context will eventually fall back to that for uselang=user.

Bug: T85635
Change-Id: I947348d87b31808d331055dac6feb0cc2e1dd15d
---
 includes/api/ApiMain.php            | 27 ++++++++++++++-------------
 includes/context/RequestContext.php |  5 ++++-
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/includes/api/ApiMain.php b/includes/api/ApiMain.php
index 1610679318..82ed295696 100644
--- a/includes/api/ApiMain.php
+++ b/includes/api/ApiMain.php
@@ -190,19 +190,20 @@ class ApiMain extends ApiBase {
 
 		$uselang = $this->getParameter( 'uselang' );
 		if ( $uselang === 'user' ) {
-			$uselang = $this->getUser()->getOption( 'language' );
-			$uselang = RequestContext::sanitizeLangCode( $uselang );
-			Hooks::run( 'UserGetLanguageObject', array( $this->getUser(), &$uselang, $this ) );
-		} elseif ( $uselang === 'content' ) {
-			global $wgContLang;
-			$uselang = $wgContLang->getCode();
-		}
-		$code = RequestContext::sanitizeLangCode( $uselang );
-		$this->getContext()->setLanguage( $code );
-		if ( !$this->mInternalMode ) {
-			global $wgLang;
-			$wgLang = $this->getContext()->getLanguage();
-			RequestContext::getMain()->setLanguage( $wgLang );
+			// Assume the parent context is going to return the user language
+			// for uselang=user (see T85635).
+		} else {
+			if ( $uselang === 'content' ) {
+				global $wgContLang;
+				$uselang = $wgContLang->getCode();
+			}
+			$code = RequestContext::sanitizeLangCode( $uselang );
+			$this->getContext()->setLanguage( $code );
+			if ( !$this->mInternalMode ) {
+				global $wgLang;
+				$wgLang = $this->getContext()->getLanguage();
+				RequestContext::getMain()->setLanguage( $wgLang );
+			}
 		}
 
 		$config = $this->getConfig();
diff --git a/includes/context/RequestContext.php b/includes/context/RequestContext.php
index 7cd229094d..a0e7f999d2 100644
--- a/includes/context/RequestContext.php
+++ b/includes/context/RequestContext.php
@@ -318,7 +318,10 @@ class RequestContext implements IContextSource {
 				$request = $this->getRequest();
 				$user = $this->getUser();
 
-				$code = $request->getVal( 'uselang', $user->getOption( 'language' ) );
+				$code = $request->getVal( 'uselang', 'user' );
+				if ( $code === 'user' ) {
+					$code = $user->getOption( 'language' );
+				}
 				$code = self::sanitizeLangCode( $code );
 
 				Hooks::run( 'UserGetLanguageObject', array( $user, &$code, $this ) );
-- 
2.20.1