From: Aaron Schulz <aschulz@wikimedia.org>
Date: Fri, 29 Mar 2019 02:39:03 +0000 (-0700)
Subject: objectcache: Remove hacky testMerge_fork() method in BagOStuffTest
X-Git-Tag: 1.34.0-rc.0~2246^2
X-Git-Url: https://git.heureux-cyclage.org/?a=commitdiff_plain;h=7ff911ba1103609cf3d6eee03d36f972d038fb21;p=lhc%2Fweb%2Fwiklou.git

objectcache: Remove hacky testMerge_fork() method in BagOStuffTest

This method easily fails due to use of the same resource in each
thread after calling pcntl_fork(). This can cause thread-safety
problems like mysqli errors, which in turn make tests fail.

Change-Id: I4ff3657940c1d1cdad58bafb7449bdd0182cbe56
---

diff --git a/tests/phpunit/includes/libs/objectcache/BagOStuffTest.php b/tests/phpunit/includes/libs/objectcache/BagOStuffTest.php
index e6b277b671..4a09a2e00d 100644
--- a/tests/phpunit/includes/libs/objectcache/BagOStuffTest.php
+++ b/tests/phpunit/includes/libs/objectcache/BagOStuffTest.php
@@ -107,77 +107,6 @@ class BagOStuffTest extends MediaWikiTestCase {
 		$this->assertEquals( $n, $calls );
 	}
 
-	/**
-	 * @covers BagOStuff::merge
-	 * @dataProvider provideTestMerge_fork
-	 */
-	public function testMerge_fork( $exists, $childWins, $resCAS ) {
-		$key = $this->cache->makeKey( self::TEST_KEY );
-		$pCallback = function ( BagOStuff $cache, $key, $oldVal ) {
-			return ( $oldVal === false ) ? 'init-parent' : $oldVal . '-merged-parent';
-		};
-		$cCallback = function ( BagOStuff $cache, $key, $oldVal ) {
-			return ( $oldVal === false ) ? 'init-child' : $oldVal . '-merged-child';
-		};
-
-		if ( $exists ) {
-			$this->cache->set( $key, 'x', 5 );
-		}
-
-		/*
-		 * Test concurrent merges by forking this process, if:
-		 * - not manually called with --use-bagostuff
-		 * - pcntl_fork is supported by the system
-		 * - cache type will correctly support calls over forks
-		 */
-		$fork = (bool)$this->getCliArg( 'use-bagostuff' );
-		$fork &= function_exists( 'pcntl_fork' );
-		$fork &= !$this->cache instanceof HashBagOStuff;
-		$fork &= !$this->cache instanceof EmptyBagOStuff;
-		$fork &= !$this->cache instanceof MultiWriteBagOStuff;
-		if ( $fork ) {
-			$pid = null;
-			// Function to start merge(), run another merge() midway through, then finish
-			$func = function ( $cache, $key, $cur ) use ( $pCallback, $cCallback, &$pid ) {
-				$pid = pcntl_fork();
-				if ( $pid == -1 ) {
-					return false;
-				} elseif ( $pid ) {
-					pcntl_wait( $status );
-
-					return $pCallback( $cache, $key, $cur );
-				} else {
-					$this->cache->merge( $key, $cCallback, 0, 1 );
-					// Bail out of the outer merge() in the child process since it does not
-					// need to attempt to write anything. Success is checked by the parent.
-					parent::tearDown(); // avoid phpunit notices
-					exit;
-				}
-			};
-
-			// attempt a merge - this should fail
-			$merged = $this->cache->merge( $key, $func, 0, 1 );
-
-			if ( $pid == -1 ) {
-				return; // can't fork, ignore this test...
-			}
-
-			// merge has failed because child process was merging (and we only attempted once)
-			$this->assertEquals( !$childWins, $merged );
-			$this->assertEquals( $this->cache->get( $key ), $resCAS );
-		} else {
-			$this->markTestSkipped( 'No pcntl methods available' );
-		}
-	}
-
-	function provideTestMerge_fork() {
-		return [
-			// (already exists, child wins CAS, result of CAS)
-			[ false, true, 'init-child' ],
-			[ true, true, 'x-merged-child' ]
-		];
-	}
-
 	/**
 	 * @covers BagOStuff::changeTTL
 	 */