Fix access to parent properties in matchers (#88)

Backport of #72.

Author: theofidry

fixtures/f008/A.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace DeepCopy\f008;
+
+class A
+{
+    private $foo;
+
+    public function __construct($foo)
+    {
+        $this->foo = $foo;
+    }
+
+    public function getFoo()
+    {
+        return $this->foo;
+    }
+}

fixtures/f008/B.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace DeepCopy\f008;
+
+class B extends A
+{
+}

src/DeepCopy/Exception/PropertyException.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace DeepCopy\Exception;
+
+use ReflectionException;
+
+class PropertyException extends ReflectionException
+{
+}

src/DeepCopy/Filter/Doctrine/DoctrineCollectionFilter.php

@@ -3,7 +3,7 @@
 namespace DeepCopy\Filter\Doctrine;
 
 use DeepCopy\Filter\Filter;
-use ReflectionProperty;
+use DeepCopy\Reflection\ReflectionHelper;
 
 /**
  * @final
@@ -17,7 +17,7 @@ class DoctrineCollectionFilter implements Filter
      */
     public function apply($object, $property, $objectCopier)
     {
-        $reflectionProperty = new ReflectionProperty($object, $property);
+        $reflectionProperty = ReflectionHelper::getProperty($object, $property);
 
         $reflectionProperty->setAccessible(true);
         $oldCollection = $reflectionProperty->getValue($object);

src/DeepCopy/Filter/Doctrine/DoctrineEmptyCollectionFilter.php

@@ -3,8 +3,8 @@
 namespace DeepCopy\Filter\Doctrine;
 
 use DeepCopy\Filter\Filter;
+use DeepCopy\Reflection\ReflectionHelper;
 use Doctrine\Common\Collections\ArrayCollection;
-use ReflectionProperty;
 
 /**
  * @final
@@ -20,7 +20,7 @@ class DoctrineEmptyCollectionFilter implements Filter
      */
     public function apply($object, $property, $objectCopier)
     {
-        $reflectionProperty = new ReflectionProperty($object, $property);
+        $reflectionProperty = ReflectionHelper::getProperty($object, $property);
         $reflectionProperty->setAccessible(true);
 
         $reflectionProperty->setValue($object, new ArrayCollection());

src/DeepCopy/Filter/ReplaceFilter.php

@@ -2,7 +2,7 @@
 
 namespace DeepCopy\Filter;
 
-use ReflectionProperty;
+use DeepCopy\Reflection\ReflectionHelper;
 
 /**
  * @final
@@ -29,7 +29,7 @@ public function __construct(callable $callable)
      */
     public function apply($object, $property, $objectCopier)
     {
-        $reflectionProperty = new ReflectionProperty($object, $property);
+        $reflectionProperty = ReflectionHelper::getProperty($object, $property);
         $reflectionProperty->setAccessible(true);
 
         $value = call_user_func($this->callback, $reflectionProperty->getValue($object));

src/DeepCopy/Filter/SetNullFilter.php

@@ -2,7 +2,7 @@
 
 namespace DeepCopy\Filter;
 
-use ReflectionProperty;
+use DeepCopy\Reflection\ReflectionHelper;
 
 /**
  * @final
@@ -16,7 +16,7 @@ class SetNullFilter implements Filter
      */
     public function apply($object, $property, $objectCopier)
     {
-        $reflectionProperty = new ReflectionProperty($object, $property);
+        $reflectionProperty = ReflectionHelper::getProperty($object, $property);
 
         $reflectionProperty->setAccessible(true);
         $reflectionProperty->setValue($object, null);

src/DeepCopy/Matcher/PropertyTypeMatcher.php

@@ -2,8 +2,8 @@
 
 namespace DeepCopy\Matcher;
 
+use DeepCopy\Reflection\ReflectionHelper;
 use ReflectionException;
-use ReflectionProperty;
 
 /**
  * Matches a property by its type.
@@ -34,7 +34,7 @@ public function __construct($propertyType)
     public function matches($object, $property)
     {
         try {
-            $reflectionProperty = new ReflectionProperty($object, $property);
+            $reflectionProperty = ReflectionHelper::getProperty($object, $property);
         } catch (ReflectionException $exception) {
             return false;
         }

src/DeepCopy/Reflection/ReflectionHelper.php

@@ -2,7 +2,10 @@
 
 namespace DeepCopy\Reflection;
 
+use DeepCopy\Exception\PropertyException;
 use ReflectionClass;
+use ReflectionException;
+use ReflectionObject;
 use ReflectionProperty;
 
 class ReflectionHelper
@@ -40,4 +43,36 @@ public static function getProperties(ReflectionClass $ref)
 
         return $propsArr;
     }
+
+    /**
+     * Retrieves property by name from object and all its ancestors.
+     *
+     * @param object|string $object
+     * @param string $name
+     *
+     * @throws PropertyException
+     * @throws ReflectionException
+     *
+     * @return ReflectionProperty
+     */
+    public static function getProperty($object, $name)
+    {
+        $reflection = is_object($object) ? new ReflectionObject($object) : new ReflectionClass($object);
+
+        if ($reflection->hasProperty($name)) {
+            return $reflection->getProperty($name);
+        }
+
+        if ($parentClass = $reflection->getParentClass()) {
+            return self::getProperty($parentClass->getName(), $name);
+        }
+
+        throw new PropertyException(
+            sprintf(
+                'The class "%s" doesn\'t have a property with the given name: "%s".',
+                is_object($object) ? get_class($object) : $object,
+                $name
+            )
+        );
+    }
 }

tests/DeepCopyTest/DeepCopyTest.php

@@ -13,9 +13,11 @@
 use DeepCopy\f004;
 use DeepCopy\f005;
 use DeepCopy\f006;
+use DeepCopy\f008;
 use DeepCopy\Filter\KeepFilter;
 use DeepCopy\Filter\SetNullFilter;
 use DeepCopy\Matcher\PropertyNameMatcher;
+use DeepCopy\Matcher\PropertyTypeMatcher;
 use DeepCopy\TypeFilter\ShallowCopyFilter;
 use DeepCopy\TypeMatcher\TypeMatcher;
 use PHPUnit_Framework_TestCase;
@@ -118,7 +120,7 @@ public function test_it_can_copy_an_object_with_an_object_property()
         $this->assertEqualButNotSame($foo->bar, $copy->bar);
     }
 
-    public function test_dynamic_properties_are_copied()
+    public function test_it_copies_dynamic_properties()
     {
         $foo = new stdClass();
         $bar = new stdClass();
@@ -375,6 +377,22 @@ public function test_it_can_copy_a_SplDoublyLinkedList()
         $this->assertEqualButNotSame($b, $aCopy->b);
     }
 
+    /**
+     * @ticket https://github.com/myclabs/DeepCopy/issues/62
+     */
+    public function test_matchers_can_access_to_parent_private_properties()
+    {
+        $deepCopy = new DeepCopy();
+        $deepCopy->addFilter(new SetNullFilter(), new PropertyTypeMatcher(stdClass::class));
+
+        $object = new f008\B(new stdClass());
+
+        /** @var f008\B $copy */
+        $copy = $deepCopy->copy($object);
+
+        $this->assertNull($copy->getFoo());
+    }
+
     private function assertEqualButNotSame($expected, $val)
     {
         $this->assertEquals($expected, $val);

tests/DeepCopyTest/Reflection/ReflectionHelperTest.php

@@ -5,6 +5,7 @@
 use DeepCopy\Reflection\ReflectionHelper;
 use PHPUnit_Framework_TestCase;
 use ReflectionClass;
+use ReflectionProperty;
 
 /**
  * @covers \DeepCopy\Reflection\ReflectionHelper
@@ -35,6 +36,39 @@ public function test_it_retrieves_the_object_properties()
 
         $this->assertSame($expectedProps, array_keys($actualProps));
     }
+
+    /**
+     * @dataProvider provideProperties
+     */
+    public function test_it_can_retrieve_an_object_property($name)
+    {
+        $object = new ReflectionHelperTestChild();
+
+        $property = ReflectionHelper::getProperty($object, $name);
+
+        $this->assertInstanceOf(ReflectionProperty::class, $property);
+
+        $this->assertSame($name, $property->getName());
+    }
+
+    public function provideProperties()
+    {
+        return [
+            'public property' => ['a10'],
+            'private property' => ['a102'],
+            'private property of ancestor' => ['a3']
+        ];
+    }
+
+    /**
+     * @expectedException \DeepCopy\Exception\PropertyException
+     */
+    public function test_it_cannot_retrieve_a_non_existent_prperty()
+    {
+        $object = new ReflectionHelperTestChild();
+
+        ReflectionHelper::getProperty($object, 'non existent property');
+    }
 }
 
 class ReflectionHelperTestParent