Make additional and pattern property names unique, closes #56

Author: vearutop

src/Structure/ObjectItemTrait.php

@@ -43,22 +43,22 @@ public function setNestedProperty($propertyName, $value, Egg $nestedEgg)
     protected $__additionalPropertyNames;
     public function addAdditionalPropertyName($name)
     {
-        $this->__additionalPropertyNames[] = $name;
+        $this->__additionalPropertyNames[$name] = true;
     }
 
     /**
      * @return null|string[]
      */
     public function getAdditionalPropertyNames()
     {
-        return $this->__additionalPropertyNames;
+        return array_keys($this->__additionalPropertyNames);
     }
 
     protected $__patternPropertyNames;
 
     public function addPatternPropertyName($pattern, $name)
     {
-        $this->__patternPropertyNames[$pattern][] = $name;
+        $this->__patternPropertyNames[$pattern][$name] = true;
     }
 
     /**
@@ -68,7 +68,7 @@ public function addPatternPropertyName($pattern, $name)
     public function getPatternPropertyNames($pattern)
     {
         if (isset($this->__patternPropertyNames[$pattern])) {
-            return $this->__patternPropertyNames[$pattern];
+            return array_keys($this->__patternPropertyNames[$pattern]);
         } else {
             return null;
         }