[PropertyAccess] ->getValue() should be read-only

Author: nicolas-grekas

src/Symfony/Component/PropertyAccess/PropertyAccessor.php

@@ -275,10 +275,11 @@ private function readPropertiesUntil($zval, PropertyPathInterface $propertyPath,
                     (is_array($zval[self::VALUE]) && !isset($zval[self::VALUE][$property]) && !array_key_exists($property, $zval[self::VALUE]))
                 ) {
                     if ($i + 1 < $propertyPath->getLength()) {
-                        $zval[self::VALUE][$property] = array();
-
                         if (isset($zval[self::REF])) {
+                            $zval[self::VALUE][$property] = array();
                             $zval[self::REF] = $zval[self::VALUE];
+                        } else {
+                            $zval[self::VALUE] = array($property => array());
                         }
                     }
                 }

src/Symfony/Component/PropertyAccess/Tests/PropertyAccessorTest.php

@@ -92,9 +92,11 @@ public function testGetValueReadsArrayWithCustomPropertyPath()
 
     public function testGetValueReadsArrayWithMissingIndexForCustomPropertyPath()
     {
-        $array = array('child' => array('index' => array()));
+        $object = new \ArrayObject();
+        $array = array('child' => array('index' => $object));
 
-        $this->assertNull($this->propertyAccessor->getValue($array, '[child][index][firstName]'));
+        $this->assertNull($this->propertyAccessor->getValue($array, '[child][index][foo][bar]'));
+        $this->assertSame(array(), $object->getArrayCopy());
     }
 
     public function testGetValueReadsProperty()