<?php
       // Exercise https://gerrit.wikimedia.org/r/c/mediawiki/core/+/439289 for  T191537 
       public function testPostSendJobDoesNotSetCookie() {

               // Prevent updates from running
               $this->setMwGlobals( 'wgCommandLineMode', false );

               // A job that attempts to set a cookie
               DeferredUpdates::addCallableUpdate( function () {
                       WebResponse::setCookie( 'JobCookie', 'yes' );
               } );

               $this->assertCount( 1,
                       DeferredUpdates::getPendingUpdates( DeferredUpdates::POSTSEND ) );

               $mw = new MediaWiki();
               $mw->doPostOutputShutdown();

               $this->assertCount( 0,
                       DeferredUpdates::getPendingUpdates( DeferredUpdates::POSTSEND ),
                       'Cookie setting job must be run'
               );
               $this->assertFalse(
                       WebResponse::hasCookies(), 'Job must not set cookie in post-send' );
              // stack traces because of headers already have been sent, but the code is good
       }