Merge branch 'hotfix/5100' into develop

Forward port zendframework/zendframework#5100

src/Exception/CircularReferenceException.php

@@ -0,0 +1,14 @@
+<?php
+/**
+ * Zend Framework (http://framework.zend.com/)
+ *
+ * @link      http://github.com/zendframework/zf2 for the canonical source repository
+ * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd New BSD License
+ */
+
+namespace Zend\ServiceManager\Exception;
+
+class CircularReferenceException extends RuntimeException
+{
+}

src/ServiceManager.php

@@ -429,6 +429,32 @@ public function setShared($name, $isShared)
         return $this;
     }
 
+    /**
+     * Resolve the alias for the given canonical name
+     *
+     * @param  string $cName The canonical name to resolve
+     * @return string The resolved canonical name
+     */
+    protected function resolveAlias($cName)
+    {
+        $stack = array();
+
+        while ($this->hasAlias($cName)) {
+            if (isset($stack[$cName])) {
+                throw new Exception\CircularReferenceException(sprintf(
+                    'Circular alias reference: %s -> %s',
+                    implode(' -> ', $stack),
+                    $cName
+                ));
+            }
+
+            $stack[$cName] = $cName;
+            $cName = $this->aliases[$cName];
+        }
+
+        return $cName;
+    }
+
     /**
      * Retrieve a registered instance
      *
@@ -448,12 +474,9 @@ public function get($name, $usePeeringServiceManagers = true)
 
         $isAlias = false;
 
-        if (isset($this->aliases[$cName])) {
+        if ($this->hasAlias($cName)) {
             $isAlias = true;
-
-            do {
-                $cName = $this->aliases[$cName];
-            } while ($this->hasAlias($cName));
+            $cName = $this->resolveAlias($cName);
         }
 
         $instance = null;
@@ -731,6 +754,38 @@ public function canCreateFromAbstractFactory($cName, $rName)
         return false;
     }
 
+    /**
+     * Ensure the alias definition will not result in a circular reference
+     *
+     * @param  string $alias
+     * @param  string $nameOrAlias
+     * @throws Exception\CircularReferenceException
+     * @return self
+     */
+    protected function checkForCircularAliasReference($alias, $nameOrAlias)
+    {
+        $aliases = $this->aliases;
+        $aliases[$alias] = $nameOrAlias;
+        $stack = array();
+
+        while (isset($aliases[$alias])) {
+            if (isset($stack[$alias])) {
+                throw new Exception\CircularReferenceException(sprintf(
+                    'The alias definition "%s" : "%s" results in a circular reference: "%s" -> "%s"',
+                    $alias,
+                    $nameOrAlias,
+                    implode('" -> "', $stack),
+                    $alias
+                ));
+            }
+
+            $stack[$alias] = $alias;
+            $alias = $aliases[$alias];
+        }
+
+        return $this;
+    }
+
     /**
      * @param  string $alias
      * @param  string $nameOrAlias
@@ -759,6 +814,10 @@ public function setAlias($alias, $nameOrAlias)
             ));
         }
 
+        if ($this->hasAlias($alias)) {
+            $this->checkForCircularAliasReference($cAlias, $nameOrAlias);
+        }
+
         $this->aliases[$cAlias] = $nameOrAlias;
         return $this;
     }

test/ServiceManagerTest.php

@@ -810,4 +810,46 @@ public function testUsesMultipleDelegates()
         $this->assertInstanceOf('stdClass', array_shift($fooDelegator->instances));
         $this->assertSame($fooDelegator, array_shift($barDelegator->instances));
     }
+
+    /**
+     * @covers Zend\ServiceManager\ServiceManager::resolveAlias
+     */
+    public function testSetCircularAliasReferenceThrowsException()
+    {
+        $this->setExpectedException('Zend\ServiceManager\Exception\CircularReferenceException');
+
+        // Only affects service managers that allow overwriting definitions
+        $this->serviceManager->setAllowOverride(true);
+        $this->serviceManager->setInvokableClass('foo-service', 'stdClass');
+        $this->serviceManager->setAlias('foo-alias', 'foo-service');
+        $this->serviceManager->setAlias('bar-alias', 'foo-alias');
+        $this->serviceManager->setAlias('baz-alias', 'bar-alias');
+
+        // This will now cause a cyclic reference and should throw an exception
+        $this->serviceManager->setAlias('foo-alias', 'bar-alias');
+    }
+
+    /**
+     * @covers Zend\ServiceManager\ServiceManager::checkForCircularAliasReference
+     */
+    public function testResolveCircularAliasReferenceThrowsException()
+    {
+        $this->setExpectedException('Zend\ServiceManager\Exception\CircularReferenceException');
+
+        // simulate an inconsistent state of $servicemanager->aliases as it could be
+        // caused by derived classes
+        $cyclicAliases = array(
+            'fooalias' => 'bazalias',
+            'baralias' => 'fooalias',
+            'bazalias' => 'baralias'
+        );
+
+        $reflection = new \ReflectionObject($this->serviceManager);
+        $propertyReflection = $reflection->getProperty('aliases');
+        $propertyReflection->setAccessible(true);
+        $propertyReflection->setValue($this->serviceManager, $cyclicAliases);
+
+        // This should throw the exception
+        $this->serviceManager->get('baz-alias');
+    }
 }