From e86ffeba3ad1e111ce5a7e082244cd2dd1602aa8 Mon Sep 17 00:00:00 2001
From: Timo Tijhof <krinklemail@gmail.com>
Date: Wed, 25 Jul 2018 00:08:25 +0100
Subject: [PATCH] Deal with <references/> inside a <ref> in automatic
 references list

The Cite extension already had a recursion guard around the parsing of
`<references/>`, to prevent another `<ref>` containing `<references/>`
from producing a weirdly nested references list.

When an explicit `<references/>` tag is not included in the page, or
`<ref>` tags exist after the last explicit `<references/>`, the extension
automatically adds a reference list at the end of the page, to make the
references still displayed.

This automatic references list creation was bypassing the recursion
guard, causing the weirdly nested output *and* a PHP Notice from
`mRefs[$group]` becoming undefined. This commit sets the recursion guard
state during that automatic references list creation to prevent this.

Bug: T182929
Change-Id: I87737dcf39a4fc15e119a1090a9c34d6b9633c21
---
 includes/Cite.php | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/includes/Cite.php b/includes/Cite.php
index 7899060b1..b3ec861b5 100644
--- a/includes/Cite.php
+++ b/includes/Cite.php
@@ -659,11 +659,12 @@ class Cite {
 	}
 
 	/**
+	 * Must only be called from references(). Use that to prevent recursion.
+	 *
 	 * @param string|null $str Raw content of the <references> tag.
 	 * @param string[] $argv
 	 * @param Parser $parser
 	 * @param string $group
-	 *
 	 * @return string
 	 */
 	private function guardedReferences(
@@ -751,7 +752,10 @@ class Cite {
 	}
 
 	/**
-	 * Make output to be returned from the references() function
+	 * Make output to be returned from the references() function.
+	 *
+	 * If called outside of references(), caller is responsible for ensuring
+	 * `mInReferences` is enabled before the call and disabled after call.
 	 *
 	 * @param string $group
 	 * @param bool $responsive
@@ -1222,7 +1226,9 @@ class Cite {
 				continue;
 			}
 			if ( $group === self::DEFAULT_GROUP || $isSectionPreview ) {
+				$this->mInReferences = true;
 				$s .= $this->referencesFormat( $group, $wgCiteResponsiveReferences );
+				$this->mInReferences = false;
 			} else {
 				$s .= "\n<br />" .
 					$this->error(