From f1c11c2c49ef706b88e99c929cd8c62684b15167 Mon Sep 17 00:00:00 2001
From: Tim Starling <tstarling@wikimedia.org>
Date: Tue, 11 Jun 2019 07:01:39 +1000
Subject: [PATCH] REST: HeaderContainer should start empty not null

Change-Id: I30b68862307f2b44e4f5708c06464e0a218c1ed5
---
 includes/Rest/HeaderContainer.php                   | 6 +++---
 tests/phpunit/includes/Rest/HeaderContainerTest.php | 1 +
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/includes/Rest/HeaderContainer.php b/includes/Rest/HeaderContainer.php
index 50f4355f2b..a71f6a6ce1 100644
--- a/includes/Rest/HeaderContainer.php
+++ b/includes/Rest/HeaderContainer.php
@@ -10,9 +10,9 @@ namespace MediaWiki\Rest;
  * Unlike PSR-7, the container is mutable.
  */
 class HeaderContainer {
-	private $headerLists;
-	private $headerLines;
-	private $headerNames;
+	private $headerLists = [];
+	private $headerLines = [];
+	private $headerNames = [];
 
 	/**
 	 * Erase any existing headers and replace them with the specified
diff --git a/tests/phpunit/includes/Rest/HeaderContainerTest.php b/tests/phpunit/includes/Rest/HeaderContainerTest.php
index d0fae9f567..e0dbfdf4f6 100644
--- a/tests/phpunit/includes/Rest/HeaderContainerTest.php
+++ b/tests/phpunit/includes/Rest/HeaderContainerTest.php
@@ -42,6 +42,7 @@ class HeaderContainerTest extends MediaWikiTestCase {
 				[ 'tesT' => [ 'bar' ] ],
 				[ 'tesT' => 'bar' ]
 			],
+			'empty' => [ [], [], [] ],
 		];
 	}
 
-- 
2.20.1