From 5a855c8625be77687f72deecbb5c7e0b66de094b Mon Sep 17 00:00:00 2001
From: Florian Schmidt <florian.schmidt.stargatewissen@gmail.com>
Date: Sat, 3 Dec 2016 18:46:48 +0100
Subject: [PATCH] registration: Don't let extensions load late

We want all extensions to be queued together and load at the same time
so in the future we can properly evaluate dependencies as a whole. If
extensions load late, they would bypass this, potentially causing
issues.

Bug: T117277
Change-Id: I09b306bd6f6ccf4210f36be0118e7f17f2c3d264
---
 includes/Setup.php                          |  4 ++-
 includes/registration/ExtensionRegistry.php | 27 +++++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/includes/Setup.php b/includes/Setup.php
index 9f722afd86..f6631eadb9 100644
--- a/includes/Setup.php
+++ b/includes/Setup.php
@@ -36,8 +36,10 @@ if ( !defined( 'MEDIAWIKI' ) ) {
 $fname = 'Setup.php';
 $ps_setup = Profiler::instance()->scopedProfileIn( $fname );
 
-// If any extensions are still queued, force load them
+// Load queued extensions
 ExtensionRegistry::getInstance()->loadFromQueue();
+// Don't let any other extensions load
+ExtensionRegistry::getInstance()->finish();
 
 // Check to see if we are at the file scope
 if ( !isset( $wgVersion ) ) {
diff --git a/includes/registration/ExtensionRegistry.php b/includes/registration/ExtensionRegistry.php
index b5c70e984b..70d247b7ec 100644
--- a/includes/registration/ExtensionRegistry.php
+++ b/includes/registration/ExtensionRegistry.php
@@ -59,6 +59,13 @@ class ExtensionRegistry {
 	 */
 	protected $queued = [];
 
+	/**
+	 * Whether we are done loading things
+	 *
+	 * @var bool
+	 */
+	private $finished = false;
+
 	/**
 	 * Items in the JSON file that aren't being
 	 * set as globals
@@ -114,12 +121,23 @@ class ExtensionRegistry {
 		$this->queued[$path] = $mtime;
 	}
 
+	/**
+	 * @throws MWException If the queue is already marked as finished (no further things should
+	 *  be loaded then).
+	 */
 	public function loadFromQueue() {
 		global $wgVersion;
 		if ( !$this->queued ) {
 			return;
 		}
 
+		if ( $this->finished ) {
+			throw new MWException(
+				"The following paths tried to load late: "
+				. implode( ', ', array_keys( $this->queued ) )
+			);
+		}
+
 		// A few more things to vary the cache on
 		$versions = [
 			'registration' => self::CACHE_VERSION,
@@ -164,6 +182,15 @@ class ExtensionRegistry {
 		$this->queued = [];
 	}
 
+	/**
+	 * After this is called, no more extensions can be loaded
+	 *
+	 * @since 1.29
+	 */
+	public function finish() {
+		$this->finished = true;
+	}
+
 	/**
 	 * Process a queue of extensions and return their extracted data
 	 *
-- 
2.20.1