Add filter prepend method (#132)

Author: fink3l

src/DeepCopy/DeepCopy.php

@@ -99,6 +99,14 @@ public function addFilter(Filter $filter, Matcher $matcher)
         ];
     }
 
+    public function prependFilter(Filter $filter, Matcher $matcher)
+    {
+        array_unshift($this->filters, [
+            'matcher' => $matcher,
+            'filter'  => $filter,
+        ]);
+    }
+
     public function addTypeFilter(TypeFilter $filter, TypeMatcher $matcher)
     {
         $this->typeFilters[] = [

tests/DeepCopyTest/DeepCopyTest.php

@@ -424,6 +424,16 @@ public function test_matchers_can_access_to_parent_private_properties()
         $this->assertNull($copy->getFoo());
     }
 
+    public function test_it_can_prepend_filter()
+    {
+        $object = new f008\A('bar');
+        $deepCopy = new DeepCopy();
+        $deepCopy->addFilter(new KeepFilter(), new PropertyNameMatcher('foo'));
+        $deepCopy->prependFilter(new SetNullFilter(), new PropertyNameMatcher('foo'));
+        $copy = $deepCopy->copy($object);
+        $this->assertNull($copy->getFoo());
+    }
+
     private function assertEqualButNotSame($expected, $val)
     {
         $this->assertEquals($expected, $val);