properly exporting $ref property

src/Constraint/Properties.php

@@ -23,6 +23,12 @@ class Properties extends ObjectItem implements Constraint
     /** @var Schema */
     protected $__schema;
 
+    /**
+     * Property to data mapping, example ["ref" => "$ref"]
+     * @var array
+     */
+    public $__defaultMapping = array();
+
     public function lock()
     {
         $this->__isReadOnly = true;
@@ -53,9 +59,6 @@ public static function create()
         return new static;
     }
 
-    /** @var Schema|null */
-    private $additionalProperties;
-
     /** @var Egg[][] */
     public $nestedProperties = array();
 
@@ -95,4 +98,31 @@ public function isEmpty()
     {
         return (count($this->__arrayOfData) + count($this->nestedProperties)) === 0;
     }
+
+    public function jsonSerialize()
+    {
+        $result = $this->__arrayOfData;
+        if ($this->__nestedObjects) {
+            foreach ($this->__nestedObjects as $object) {
+                foreach ($object->toArray() as $key => $value) {
+                    $result[$key] = $value;
+                }
+            }
+        }
+
+        if (isset($this->__defaultMapping)) {
+            $mappedResult = new \stdClass();
+            foreach ($result as $key => $value) {
+                if (isset($this->__defaultMapping[$key])) {
+                    $mappedResult->{$this->__defaultMapping[$key]} = $value;
+                } else {
+                    $mappedResult->$key = $value;
+                }
+            }
+            return $mappedResult;
+        }
+
+        return (object)$result;
+    }
+
 }

src/Schema.php

@@ -91,6 +91,10 @@ public function addPropertyMapping($dataName, $propertyName, $mapping = self::DE
     {
         $this->__dataToProperty[$mapping][$dataName] = $propertyName;
         $this->__propertyToData[$mapping][$propertyName] = $dataName;
+
+        if ($mapping === self::DEFAULT_MAPPING && $this->properties instanceof Properties) {
+            $this->properties->__defaultMapping[$propertyName] = $dataName;
+        }
         return $this;
     }
 

src/Wrapper.php

@@ -75,15 +75,15 @@ public function out($data, Context $options = null)
      */
     public function getPropertyNames()
     {
-        return array_keys($this->schema->getProperties()->toArray());
+        return $this->schema->getPropertyNames();
     }
 
     /**
      * @return string[]
      */
     public function getNestedPropertyNames()
     {
-        return $this->schema->getProperties()->nestedPropertyNames;
+        return $this->schema->getNestedPropertyNames();
     }
 
     public function nested()

tests/src/Helper/RefClass.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Swaggest\JsonSchema\Tests\Helper;
+
+
+use Swaggest\JsonSchema\Constraint\Format;
+use Swaggest\JsonSchema\Constraint\Properties;
+use Swaggest\JsonSchema\Schema;
+use Swaggest\JsonSchema\Structure\ClassStructure;
+
+class RefClass extends ClassStructure
+{
+
+    public $ref;
+
+    /**
+     * @param Properties|static $properties
+     * @param Schema $ownerSchema
+     */
+    public static function setUpProperties($properties, Schema $ownerSchema)
+    {
+        $properties->ref = Schema::string();
+        $properties->ref->format = Format::URI_REFERENCE;
+
+        $ownerSchema->addPropertyMapping('$ref', self::names()->ref);
+    }
+}

tests/src/PHPUnit/Schema/ExportTest.php

@@ -5,6 +5,7 @@
 
 use Swaggest\JsonSchema\Schema;
 use Swaggest\JsonSchema\Structure\ObjectItem;
+use Swaggest\JsonSchema\Tests\Helper\RefClass;
 
 class ExportTest extends \PHPUnit_Framework_TestCase
 {
@@ -162,4 +163,15 @@ public function testVeryNestedObjectWithReference()
         $this->assertTrue($exported->veryNestedObject->nesteder instanceof \stdClass);
     }
 
+    public function testRefClass()
+    {
+        $schema = RefClass::schema()->exportSchema();
+        $this->assertSame('{"properties":{"$ref":{"type":"string","format":"uri-reference"}}}', json_encode($schema));
+        $schemaData = Schema::export($schema);
+        $this->assertSame(
+            '{"properties":{"$ref":{"type":"string","format":"uri-reference"}}}',
+            json_encode($schemaData, JSON_UNESCAPED_SLASHES)
+        );
+    }
+
 }