diff --git a/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache b/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache
index e89dd01d51e..9550de6d193 100644
--- a/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache
+++ b/modules/swagger-codegen/src/main/resources/php/ObjectSerializer.mustache
@@ -204,7 +204,7 @@ class ObjectSerializer
      *
      * @return object|array|null an single or an array of $class instances
      */
-    public static function deserialize($data, $class, $httpHeaders = null, $discriminator = null)
+    public static function deserialize($data, $class, $httpHeaders = null)
     {
         if (null === $data) {
             return null;
@@ -215,7 +215,7 @@ class ObjectSerializer
                 $subClass_array = explode(',', $inner, 2);
                 $subClass = $subClass_array[1];
                 foreach ($data as $key => $value) {
-                    $deserialized[$key] = self::deserialize($value, $subClass, null, $discriminator);
+                    $deserialized[$key] = self::deserialize($value, $subClass, null);
                 }
             }
             return $deserialized;
@@ -223,7 +223,7 @@ class ObjectSerializer
             $subClass = substr($class, 0, -2);
             $values = [];
             foreach ($data as $key => $value) {
-                $values[] = self::deserialize($value, $subClass, null, $discriminator);
+                $values[] = self::deserialize($value, $subClass, null);
             }
             return $values;
         } elseif ($class === 'object') {
@@ -261,6 +261,7 @@ class ObjectSerializer
             return $deserialized;
         } else {
             // If a discriminator is defined and points to a valid subclass, use it.
+            $discriminator = $class::DISCRIMINATOR;
             if (!empty($discriminator) && isset($data->{$discriminator}) && is_string($data->{$discriminator})) {
                 $subclass = '\{{invokerPackage}}\Model\\' . $data->{$discriminator};
                 if (is_subclass_of($subclass, $class)) {
@@ -277,7 +278,7 @@ class ObjectSerializer
 
                 $propertyValue = $data->{$instance::attributeMap()[$property]};
                 if (isset($propertyValue)) {
-                    $instance->$propertySetter(self::deserialize($propertyValue, $type, null, $discriminator));
+                    $instance->$propertySetter(self::deserialize($propertyValue, $type, null));
                 }
             }
             return $instance;
diff --git a/modules/swagger-codegen/src/main/resources/php/api.mustache b/modules/swagger-codegen/src/main/resources/php/api.mustache
index 2148d1ea9ad..1768ff7ac5e 100644
--- a/modules/swagger-codegen/src/main/resources/php/api.mustache
+++ b/modules/swagger-codegen/src/main/resources/php/api.mustache
@@ -284,7 +284,7 @@ use \{{invokerPackage}}\ObjectSerializer;
             );
 
             {{#returnType}}
-            return [$this->apiClient->getSerializer()->deserialize($response, '{{returnType}}', $httpHeader{{#discriminator}}, '{{discriminator}}'{{/discriminator}}), $statusCode, $httpHeader];
+            return [$this->apiClient->getSerializer()->deserialize($response, '{{returnType}}', $httpHeader), $statusCode, $httpHeader];
             {{/returnType}}
             {{^returnType}}
             return [null, $statusCode, $httpHeader];
diff --git a/modules/swagger-codegen/src/main/resources/php/model_generic.mustache b/modules/swagger-codegen/src/main/resources/php/model_generic.mustache
index 1e221b78377..f7ab60ad616 100644
--- a/modules/swagger-codegen/src/main/resources/php/model_generic.mustache
+++ b/modules/swagger-codegen/src/main/resources/php/model_generic.mustache
@@ -1,5 +1,7 @@
 class {{classname}} {{#parentSchema}}extends {{{parent}}} {{/parentSchema}}implements ArrayAccess
 {
+    const DISCRIMINATOR = {{#discriminator}}'{{discriminator}}'{{/discriminator}}{{^discriminator}}null{{/discriminator}};
+
     /**
       * The original name of the model.
       * @var string
@@ -103,8 +105,8 @@ class {{classname}} {{#parentSchema}}extends {{{parent}}} {{/parentSchema}}imple
         {{#discriminator}}
 
         // Initialize discriminator property with the model name.
-        $discrimintor = array_search('{{discriminator}}', self::$attributeMap);
-        $this->container[$discrimintor] = static::$swaggerModelName;
+        $discriminator = array_search('{{discriminator}}', self::$attributeMap);
+        $this->container[$discriminator] = static::$swaggerModelName;
         {{/discriminator}}
     }
 
@@ -370,4 +372,4 @@ class {{classname}} {{#parentSchema}}extends {{{parent}}} {{/parentSchema}}imple
 
         return json_encode(\{{invokerPackage}}\ObjectSerializer::sanitizeForSerialization($this));
     }
-}
\ No newline at end of file
+}
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/.php_cs b/samples/client/petstore-security-test/php/SwaggerClient-php/.php_cs
new file mode 100644
index 00000000000..6b8e23c818a
--- /dev/null
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/.php_cs
@@ -0,0 +1,18 @@
+<?php
+
+return Symfony\CS\Config::create()
+    ->level(Symfony\CS\FixerInterface::PSR2_LEVEL)
+    ->setUsingCache(true)
+    ->fixers(
+        [
+            'ordered_use',
+            'phpdoc_order',
+            'short_array_syntax',
+            'strict',
+            'strict_param'
+        ]
+    )
+    ->finder(
+        Symfony\CS\Finder\DefaultFinder::create()
+            ->in(__DIR__)
+    );
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/.travis.yml b/samples/client/petstore-security-test/php/SwaggerClient-php/.travis.yml
index 3c97d942552..d77f3825f6f 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/.travis.yml
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/.travis.yml
@@ -7,4 +7,4 @@ php:
     - 7.0
     - hhvm
 before_install: "composer install"
-script: "phpunit lib/Tests"
+script: "vendor/bin/phpunit"
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/README.md b/samples/client/petstore-security-test/php/SwaggerClient-php/README.md
index baa8eb42188..e25623732e0 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/README.md
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/README.md
@@ -4,7 +4,6 @@ This spec is mainly for testing Petstore server and contains fake endpoints, mod
 This PHP package is automatically generated by the [Swagger Codegen](https://github.com/swagger-api/swagger-codegen) project:
 
 - API version: 1.0.0 *_/ &#39; \&quot; &#x3D;end -- \\r\\n \\n \\r
-- Build date: 2016-08-05T11:24:40.650+02:00
 - Build package: class io.swagger.codegen.languages.PhpClientCodegen
 
 ## Requirements
@@ -46,7 +45,7 @@ To run the unit tests:
 
 ```
 composer install
-./vendor/bin/phpunit lib/Tests
+./vendor/bin/phpunit
 ```
 
 ## Getting Started
@@ -86,20 +85,20 @@ Class | Method | HTTP request | Description
 ## Documentation For Authorization
 
 
+## api_key
+
+- **Type**: API key
+- **API key parameter name**: api_key  */ ' " =end -- \r\n \n \r
+- **Location**: HTTP header
+
 ## petstore_auth
 
 - **Type**: OAuth
 - **Flow**: implicit
 - **Authorization URL**: http://petstore.swagger.io/api/oauth/dialog
 - **Scopes**: 
- - **write:pets**: modify pets in your account  */ ' " =end -- \r\n \n \r
- - **read:pets**: read your pets  */ ' " =end -- \r\n \n \r
-
-## api_key
-
-- **Type**: API key
-- **API key parameter name**: api_key  */ ' " =end -- \r\n \n \r
-- **Location**: HTTP header
+ - **write:pets**: modify pets in your account  *_/ ' \" =end -- \\r\\n \\n \\r
+ - **read:pets**: read your pets  *_/ ' \" =end -- \\r\\n \\n \\r
 
 
 ## Author
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/composer.json b/samples/client/petstore-security-test/php/SwaggerClient-php/composer.json
index b9290bdacb9..78602f3be45 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/composer.json
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/composer.json
@@ -8,7 +8,7 @@
         "api"
     ],
     "homepage": "http://swagger.io",
-    "license": "Apache v2",
+    "license": "Apache-2.0",
     "authors": [
         {
             "name": "Swagger and contributors",
@@ -24,7 +24,8 @@
     "require-dev": {
         "phpunit/phpunit": "~4.8",
         "satooshi/php-coveralls": "~1.0",
-        "squizlabs/php_codesniffer": "~2.6"
+        "squizlabs/php_codesniffer": "~2.6",
+        "friendsofphp/php-cs-fixer": "~1.12"
     },
     "autoload": {
         "psr-4": { "Swagger\\Client\\" : "lib/" }
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php
index 5ce09b9a7ec..d399e789de5 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Api/FakeApi.php
@@ -40,9 +40,9 @@
 
 namespace Swagger\Client\Api;
 
-use \Swagger\Client\Configuration;
 use \Swagger\Client\ApiClient;
 use \Swagger\Client\ApiException;
+use \Swagger\Client\Configuration;
 use \Swagger\Client\ObjectSerializer;
 
 /**
@@ -56,7 +56,6 @@ use \Swagger\Client\ObjectSerializer;
  */
 class FakeApi
 {
-
     /**
      * API Client
      *
@@ -71,7 +70,7 @@ class FakeApi
      */
     public function __construct(\Swagger\Client\ApiClient $apiClient = null)
     {
-        if ($apiClient == null) {
+        if ($apiClient === null) {
             $apiClient = new ApiClient();
             $apiClient->getConfig()->setHost('https://petstore.swagger.io *_/ &#39; \&quot; &#x3D;end -- \\r\\n \\n \\r/v2 *_/ &#39; \&quot; &#x3D;end -- \\r\\n \\n \\r');
         }
@@ -108,8 +107,8 @@ class FakeApi
      * To test code injection *_/ ' \" =end -- \\r\\n \\n \\r
      *
      * @param string $test_code_inject____end____rn_n_r To test code injection *_/ &#39; \&quot; &#x3D;end -- \\r\\n \\n \\r (optional)
-     * @return void
      * @throws \Swagger\Client\ApiException on non-2xx response
+     * @return void
      */
     public function testCodeInjectEndRnNR($test_code_inject____end____rn_n_r = null)
     {
@@ -123,22 +122,22 @@ class FakeApi
      * To test code injection *_/ ' \" =end -- \\r\\n \\n \\r
      *
      * @param string $test_code_inject____end____rn_n_r To test code injection *_/ &#39; \&quot; &#x3D;end -- \\r\\n \\n \\r (optional)
-     * @return Array of null, HTTP status code, HTTP response headers (array of strings)
      * @throws \Swagger\Client\ApiException on non-2xx response
+     * @return array of null, HTTP status code, HTTP response headers (array of strings)
      */
     public function testCodeInjectEndRnNRWithHttpInfo($test_code_inject____end____rn_n_r = null)
     {
         // parse inputs
         $resourcePath = "/fake";
         $httpBody = '';
-        $queryParams = array();
-        $headerParams = array();
-        $formParams = array();
-        $_header_accept = $this->apiClient->selectHeaderAccept(array('application/json', '*_/  \" =end --'));
+        $queryParams = [];
+        $headerParams = [];
+        $formParams = [];
+        $_header_accept = $this->apiClient->selectHeaderAccept(['application/json', '*_/  \" =end --']);
         if (!is_null($_header_accept)) {
             $headerParams['Accept'] = $_header_accept;
         }
-        $headerParams['Content-Type'] = $this->apiClient->selectHeaderContentType(array('application/json','*_/  \" =end --'));
+        $headerParams['Content-Type'] = $this->apiClient->selectHeaderContentType(['application/json', '*_/  \" =end --']);
 
         // default format to json
         $resourcePath = str_replace("{format}", "json", $resourcePath);
@@ -166,7 +165,7 @@ class FakeApi
                 '/fake'
             );
 
-            return array(null, $statusCode, $httpHeader);
+            return [null, $statusCode, $httpHeader];
         } catch (ApiException $e) {
             switch ($e->getCode()) {
             }
@@ -174,5 +173,4 @@ class FakeApi
             throw $e;
         }
     }
-
 }
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ApiClient.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ApiClient.php
index 5f774a834d3..c8d7f70fedb 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ApiClient.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ApiClient.php
@@ -52,7 +52,6 @@ namespace Swagger\Client;
  */
 class ApiClient
 {
-
     public static $PATCH = "PATCH";
     public static $POST = "POST";
     public static $GET = "GET";
@@ -82,7 +81,7 @@ class ApiClient
      */
     public function __construct(\Swagger\Client\Configuration $config = null)
     {
-        if ($config == null) {
+        if ($config === null) {
             $config = Configuration::getDefaultConfiguration();
         }
 
@@ -151,8 +150,7 @@ class ApiClient
      */
     public function callApi($resourcePath, $method, $queryParams, $postData, $headerParams, $responseType = null, $endpointPath = null)
     {
-
-        $headers = array();
+        $headers = [];
 
         // construct the http header
         $headerParams = array_merge(
@@ -165,9 +163,9 @@ class ApiClient
         }
 
         // form data
-        if ($postData and in_array('Content-Type: application/x-www-form-urlencoded', $headers)) {
+        if ($postData and in_array('Content-Type: application/x-www-form-urlencoded', $headers, true)) {
             $postData = http_build_query($postData);
-        } elseif ((is_object($postData) or is_array($postData)) and !in_array('Content-Type: multipart/form-data', $headers)) { // json model
+        } elseif ((is_object($postData) or is_array($postData)) and !in_array('Content-Type: multipart/form-data', $headers, true)) { // json model
             $postData = json_encode(\Swagger\Client\ObjectSerializer::sanitizeForSerialization($postData));
         }
 
@@ -175,7 +173,7 @@ class ApiClient
 
         $curl = curl_init();
         // set timeout, if needed
-        if ($this->config->getCurlTimeout() != 0) {
+        if ($this->config->getCurlTimeout() !== 0) {
             curl_setopt($curl, CURLOPT_TIMEOUT, $this->config->getCurlTimeout());
         }
         // return the result on success, rather than just true
@@ -184,7 +182,7 @@ class ApiClient
         curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);
 
         // disable SSL verification, if needed
-        if ($this->config->getSSLVerification() == false) {
+        if ($this->config->getSSLVerification() === false) {
             curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, 0);
             curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 0);
         }
@@ -193,24 +191,24 @@ class ApiClient
             $url = ($url . '?' . http_build_query($queryParams));
         }
 
-        if ($method == self::$POST) {
+        if ($method === self::$POST) {
             curl_setopt($curl, CURLOPT_POST, true);
             curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
-        } elseif ($method == self::$HEAD) {
+        } elseif ($method === self::$HEAD) {
             curl_setopt($curl, CURLOPT_NOBODY, true);
-        } elseif ($method == self::$OPTIONS) {
+        } elseif ($method === self::$OPTIONS) {
             curl_setopt($curl, CURLOPT_CUSTOMREQUEST, "OPTIONS");
             curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
-        } elseif ($method == self::$PATCH) {
+        } elseif ($method === self::$PATCH) {
             curl_setopt($curl, CURLOPT_CUSTOMREQUEST, "PATCH");
             curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
-        } elseif ($method == self::$PUT) {
+        } elseif ($method === self::$PUT) {
             curl_setopt($curl, CURLOPT_CUSTOMREQUEST, "PUT");
             curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
-        } elseif ($method == self::$DELETE) {
+        } elseif ($method === self::$DELETE) {
             curl_setopt($curl, CURLOPT_CUSTOMREQUEST, "DELETE");
             curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
-        } elseif ($method != self::$GET) {
+        } elseif ($method !== self::$GET) {
             throw new ApiException('Method ' . $method . ' is not recognized.');
         }
         curl_setopt($curl, CURLOPT_URL, $url);
@@ -244,7 +242,7 @@ class ApiClient
         }
 
         // Handle the response
-        if ($response_info['http_code'] == 0) {
+        if ($response_info['http_code'] === 0) {
             $curl_error_message = curl_error($curl);
 
             // curl_exec can sometimes fail but still return a blank message from curl_error().
@@ -260,8 +258,8 @@ class ApiClient
             throw $exception;
         } elseif ($response_info['http_code'] >= 200 && $response_info['http_code'] <= 299) {
             // return raw body if response is a file
-            if ($responseType == '\SplFileObject' || $responseType == 'string') {
-                return array($http_body, $response_info['http_code'], $http_header);
+            if ($responseType === '\SplFileObject' || $responseType === 'string') {
+                return [$http_body, $response_info['http_code'], $http_header];
             }
 
             $data = json_decode($http_body);
@@ -281,7 +279,7 @@ class ApiClient
                 $data
             );
         }
-        return array($data, $response_info['http_code'], $http_header);
+        return [$data, $response_info['http_code'], $http_header];
     }
 
     /**
@@ -330,7 +328,7 @@ class ApiClient
     protected function httpParseHeaders($raw_headers)
     {
         // ref/credit: http://php.net/manual/en/function.http-parse-headers.php#112986
-        $headers = array();
+        $headers = [];
         $key = '';
 
         foreach (explode("\n", $raw_headers) as $h) {
@@ -340,14 +338,14 @@ class ApiClient
                 if (!isset($headers[$h[0]])) {
                     $headers[$h[0]] = trim($h[1]);
                 } elseif (is_array($headers[$h[0]])) {
-                    $headers[$h[0]] = array_merge($headers[$h[0]], array(trim($h[1])));
+                    $headers[$h[0]] = array_merge($headers[$h[0]], [trim($h[1])]);
                 } else {
-                    $headers[$h[0]] = array_merge(array($headers[$h[0]]), array(trim($h[1])));
+                    $headers[$h[0]] = array_merge([$headers[$h[0]]], [trim($h[1])]);
                 }
 
                 $key = $h[0];
             } else {
-                if (substr($h[0], 0, 1) == "\t") {
+                if (substr($h[0], 0, 1) === "\t") {
                     $headers[$key] .= "\r\n\t".trim($h[0]);
                 } elseif (!$key) {
                     $headers[0] = trim($h[0]);
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php
index 12c2b9b0ea2..69c7ce6bcbd 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Configuration.php
@@ -52,7 +52,6 @@ namespace Swagger\Client;
  */
 class Configuration
 {
-
     private static $defaultConfiguration = null;
 
     /**
@@ -60,14 +59,14 @@ class Configuration
      *
      * @var string[]
      */
-    protected $apiKeys = array();
+    protected $apiKeys = [];
 
     /**
      * Associate array to store API prefix (e.g. Bearer)
      *
      * @var string[]
      */
-    protected $apiKeyPrefixes = array();
+    protected $apiKeyPrefixes = [];
 
     /**
      * Access token for OAuth
@@ -91,11 +90,11 @@ class Configuration
     protected $password = '';
 
     /**
-     * The default instance of ApiClient
+     * The default header(s)
      *
-     * @var \Swagger\Client\ApiClient
+     * @var array
      */
-    protected $defaultHeaders = array();
+    protected $defaultHeaders = [];
 
     /**
      * The host
@@ -283,7 +282,7 @@ class Configuration
      * @param string $headerName  header name (e.g. Token)
      * @param string $headerValue header value (e.g. 1z8wp3)
      *
-     * @return ApiClient
+     * @return Configuration
      */
     public function addDefaultHeader($headerName, $headerValue)
     {
@@ -345,7 +344,7 @@ class Configuration
      *
      * @param string $userAgent the user agent of the api client
      *
-     * @return ApiClient
+     * @return Configuration
      */
     public function setUserAgent($userAgent)
     {
@@ -372,7 +371,7 @@ class Configuration
      *
      * @param integer $seconds Number of seconds before timing out [set to 0 for no timeout]
      *
-     * @return ApiClient
+     * @return Configuration
      */
     public function setCurlTimeout($seconds)
     {
@@ -493,7 +492,7 @@ class Configuration
      */
     public static function getDefaultConfiguration()
     {
-        if (self::$defaultConfiguration == null) {
+        if (self::$defaultConfiguration === null) {
             self::$defaultConfiguration = new Configuration();
         }
 
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Model/ModelReturn.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Model/ModelReturn.php
index c4baed23baa..2eade42511f 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Model/ModelReturn.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/Model/ModelReturn.php
@@ -48,7 +48,7 @@ use \ArrayAccess;
  *
  * @category    Class */
  // @description Model for testing reserved words  *_/ &#39; \&quot; &#x3D;end -- \\r\\n \\n \\r
-/** 
+/**
  * @package     Swagger\Client
  * @author      http://github.com/swagger-api/swagger-codegen
  * @license     http://www.apache.org/licenses/LICENSE-2.0 Apache License v2
@@ -56,6 +56,8 @@ use \ArrayAccess;
  */
 class ModelReturn implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
@@ -66,9 +68,9 @@ class ModelReturn implements ArrayAccess
       * Array of property to type mappings. Used for (de)serialization
       * @var string[]
       */
-    protected static $swaggerTypes = array(
+    protected static $swaggerTypes = [
         'return' => 'int'
-    );
+    ];
 
     public static function swaggerTypes()
     {
@@ -79,36 +81,38 @@ class ModelReturn implements ArrayAccess
      * Array of attributes where the key is the local name, and the value is the original name
      * @var string[]
      */
-    protected static $attributeMap = array(
+    protected static $attributeMap = [
         'return' => 'return'
-    );
+    ];
+
+
+    /**
+     * Array of attributes to setter functions (for deserialization of responses)
+     * @var string[]
+     */
+    protected static $setters = [
+        'return' => 'setReturn'
+    ];
+
+
+    /**
+     * Array of attributes to getter functions (for serialization of requests)
+     * @var string[]
+     */
+    protected static $getters = [
+        'return' => 'getReturn'
+    ];
 
     public static function attributeMap()
     {
         return self::$attributeMap;
     }
 
-    /**
-     * Array of attributes to setter functions (for deserialization of responses)
-     * @var string[]
-     */
-    protected static $setters = array(
-        'return' => 'setReturn'
-    );
-
     public static function setters()
     {
         return self::$setters;
     }
 
-    /**
-     * Array of attributes to getter functions (for serialization of requests)
-     * @var string[]
-     */
-    protected static $getters = array(
-        'return' => 'getReturn'
-    );
-
     public static function getters()
     {
         return self::$getters;
@@ -122,11 +126,11 @@ class ModelReturn implements ArrayAccess
      * Associative array for storing property values
      * @var mixed[]
      */
-    protected $container = array();
+    protected $container = [];
 
     /**
      * Constructor
-     * @param mixed[] $data Associated array of property value initalizing the model
+     * @param mixed[] $data Associated array of property values initializing the model
      */
     public function __construct(array $data = null)
     {
@@ -140,7 +144,7 @@ class ModelReturn implements ArrayAccess
      */
     public function listInvalidProperties()
     {
-        $invalid_properties = array();
+        $invalid_properties = [];
         return $invalid_properties;
     }
 
@@ -235,4 +239,3 @@ class ModelReturn implements ArrayAccess
     }
 }
 
-
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php
index f5ce9361286..c72c36f24fd 100644
--- a/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/lib/ObjectSerializer.php
@@ -52,13 +52,12 @@ namespace Swagger\Client;
  */
 class ObjectSerializer
 {
-
     /**
      * Serialize data
      *
      * @param mixed $data the data to serialize
      *
-     * @return string serialized form of $data
+     * @return string|object serialized form of $data
      */
     public static function sanitizeForSerialization($data)
     {
@@ -72,7 +71,7 @@ class ObjectSerializer
             }
             return $data;
         } elseif (is_object($data)) {
-            $values = array();
+            $values = [];
             foreach (array_keys($data::swaggerTypes()) as $property) {
                 $getter = $data::getters()[$property];
                 if ($data->$getter() !== null) {
@@ -121,7 +120,7 @@ class ObjectSerializer
      * If it's a string, pass through unchanged. It will be url-encoded
      * later.
      *
-     * @param object $object an object to be serialized to a string
+     * @param string[]|string|\DateTime $object an object to be serialized to a string
      *
      * @return string the serialized object
      */
@@ -153,7 +152,7 @@ class ObjectSerializer
      * the http body (form parameter). If it's a string, pass through unchanged
      * If it's a datetime object, format it in ISO8601
      *
-     * @param string $value the value of the form parameter
+     * @param string|\SplFileObject $value the value of the form parameter
      *
      * @return string the form string
      */
@@ -171,7 +170,7 @@ class ObjectSerializer
      * the parameter. If it's a string, pass through unchanged
      * If it's a datetime object, format it in ISO8601
      *
-     * @param string $value the value of the parameter
+     * @param string|\DateTime $value the value of the parameter
      *
      * @return string the header string
      */
@@ -187,9 +186,10 @@ class ObjectSerializer
     /**
      * Serialize an array to a string.
      *
-     * @param array  $collection       collection to serialize to a string
-     * @param string $collectionFormat the format use for serialization (csv,
+     * @param array  $collection                 collection to serialize to a string
+     * @param string $collectionFormat           the format use for serialization (csv,
      * ssv, tsv, pipes, multi)
+     * @param bool   $allowCollectionFormatMulti allow collection format to be a multidimensional array
      *
      * @return string
      */
@@ -220,33 +220,33 @@ class ObjectSerializer
     /**
      * Deserialize a JSON string into an object
      *
-     * @param mixed  $data          object or primitive to be deserialized
-     * @param string $class         class name is passed as a string
-     * @param string $httpHeaders   HTTP headers
-     * @param string $discriminator discriminator if polymorphism is used
+     * @param mixed    $data          object or primitive to be deserialized
+     * @param string   $class         class name is passed as a string
+     * @param string[] $httpHeaders   HTTP headers
+     * @param string   $discriminator discriminator if polymorphism is used
      *
-     * @return object an instance of $class
+     * @return object|array|null an single or an array of $class instances
      */
-    public static function deserialize($data, $class, $httpHeaders = null, $discriminator = null)
+    public static function deserialize($data, $class, $httpHeaders = null)
     {
         if (null === $data) {
             return null;
         } elseif (substr($class, 0, 4) === 'map[') { // for associative array e.g. map[string,int]
             $inner = substr($class, 4, -1);
-            $deserialized = array();
+            $deserialized = [];
             if (strrpos($inner, ",") !== false) {
                 $subClass_array = explode(',', $inner, 2);
                 $subClass = $subClass_array[1];
                 foreach ($data as $key => $value) {
-                    $deserialized[$key] = self::deserialize($value, $subClass, null, $discriminator);
+                    $deserialized[$key] = self::deserialize($value, $subClass, null);
                 }
             }
             return $deserialized;
-        } elseif (strcasecmp(substr($class, -2), '[]') == 0) {
+        } elseif (strcasecmp(substr($class, -2), '[]') === 0) {
             $subClass = substr($class, 0, -2);
-            $values = array();
+            $values = [];
             foreach ($data as $key => $value) {
-                $values[] = self::deserialize($value, $subClass, null, $discriminator);
+                $values[] = self::deserialize($value, $subClass, null);
             }
             return $values;
         } elseif ($class === 'object') {
@@ -264,7 +264,7 @@ class ObjectSerializer
             } else {
                 return null;
             }
-        } elseif (in_array($class, array('void', 'bool', 'string', 'double', 'byte', 'mixed', 'integer', 'float', 'int', 'DateTime', 'number', 'boolean', 'object'))) {
+        } elseif (in_array($class, ['DateTime', 'bool', 'boolean', 'byte', 'double', 'float', 'int', 'integer', 'mixed', 'number', 'object', 'string', 'void'], true)) {
             settype($data, $class);
             return $data;
         } elseif ($class === '\SplFileObject') {
@@ -277,7 +277,6 @@ class ObjectSerializer
             }
             $deserialized = new \SplFileObject($filename, "w");
             $byte_written = $deserialized->fwrite($data);
- 
             if (Configuration::getDefaultConfiguration()->getDebug()) {
                 error_log("[DEBUG] Written $byte_written byte to $filename. Please move the file to a proper folder or delete the temp file after processing.".PHP_EOL, 3, Configuration::getDefaultConfiguration()->getDebugFile());
             }
@@ -285,6 +284,7 @@ class ObjectSerializer
             return $deserialized;
         } else {
             // If a discriminator is defined and points to a valid subclass, use it.
+            $discriminator = $class::DISCRIMINATOR;
             if (!empty($discriminator) && isset($data->{$discriminator}) && is_string($data->{$discriminator})) {
                 $subclass = '\Swagger\Client\Model\\' . $data->{$discriminator};
                 if (is_subclass_of($subclass, $class)) {
@@ -301,7 +301,7 @@ class ObjectSerializer
 
                 $propertyValue = $data->{$instance::attributeMap()[$property]};
                 if (isset($propertyValue)) {
-                    $instance->$propertySetter(self::deserialize($propertyValue, $type, null, $discriminator));
+                    $instance->$propertySetter(self::deserialize($propertyValue, $type, null));
                 }
             }
             return $instance;
diff --git a/samples/client/petstore-security-test/php/SwaggerClient-php/phpunit.xml.dist b/samples/client/petstore-security-test/php/SwaggerClient-php/phpunit.xml.dist
new file mode 100644
index 00000000000..c12ee148477
--- /dev/null
+++ b/samples/client/petstore-security-test/php/SwaggerClient-php/phpunit.xml.dist
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit bootstrap="./vendor/autoload.php"
+         colors="true"
+         convertErrorsToExceptions="true"
+         convertNoticesToExceptions="true"
+         convertWarningsToExceptions="true"
+         stopOnFailure="false">
+    <testsuites>
+        <testsuite>
+            <directory>./test/Api</directory>
+            <directory>./test/Model</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist processUncoveredFilesFromWhitelist="true">
+            <directory suffix=".php">./lib/Api</directory>
+            <directory suffix=".php">./lib/Model</directory>
+        </whitelist>
+    </filter>
+</phpunit>
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/AdditionalPropertiesClass.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/AdditionalPropertiesClass.php
index 0cbdb8b1220..60c0799ecc3 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/AdditionalPropertiesClass.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/AdditionalPropertiesClass.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class AdditionalPropertiesClass implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Animal.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Animal.php
index 9344dd618f7..06625475509 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Animal.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Animal.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Animal implements ArrayAccess
 {
+    const DISCRIMINATOR = 'className';
+
     /**
       * The original name of the model.
       * @var string
@@ -126,8 +128,8 @@ class Animal implements ArrayAccess
         $this->container['color'] = isset($data['color']) ? $data['color'] : 'red';
 
         // Initialize discriminator property with the model name.
-        $discrimintor = array_search('className', self::$attributeMap);
-        $this->container[$discrimintor] = static::$swaggerModelName;
+        $discriminator = array_search('className', self::$attributeMap);
+        $this->container[$discriminator] = static::$swaggerModelName;
     }
 
     /**
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/AnimalFarm.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/AnimalFarm.php
index 185f7b2e772..a814b227c14 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/AnimalFarm.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/AnimalFarm.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class AnimalFarm implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ApiResponse.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ApiResponse.php
index dd78695f4ae..1240d1f3efb 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ApiResponse.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ApiResponse.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class ApiResponse implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfArrayOfNumberOnly.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfArrayOfNumberOnly.php
index f21da5a742d..060c16dc443 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfArrayOfNumberOnly.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfArrayOfNumberOnly.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class ArrayOfArrayOfNumberOnly implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfNumberOnly.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfNumberOnly.php
index d9b64bbe0ae..eac1a959200 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfNumberOnly.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayOfNumberOnly.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class ArrayOfNumberOnly implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayTest.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayTest.php
index be4bc7b0231..e3266c65b0c 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayTest.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ArrayTest.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class ArrayTest implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Cat.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Cat.php
index fdaa49e31f8..fbab168ade9 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Cat.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Cat.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Cat extends Animal implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Category.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Category.php
index 1258907ffec..b3f6ffc1c7c 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Category.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Category.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Category implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Client.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Client.php
index 558469ed5db..55ef2a1918a 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Client.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Client.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Client implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Dog.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Dog.php
index 898e96f5373..2888805e717 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Dog.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Dog.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Dog extends Animal implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php
index 548de3b160f..c2bc15def85 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class EnumArrays implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php
index dcfd407d690..b0ba03e5748 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class EnumTest implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/FormatTest.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/FormatTest.php
index 39fc6cf385a..72c8f79a357 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/FormatTest.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/FormatTest.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class FormatTest implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/HasOnlyReadOnly.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/HasOnlyReadOnly.php
index 75520744546..6251620638f 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/HasOnlyReadOnly.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/HasOnlyReadOnly.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class HasOnlyReadOnly implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/MapTest.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/MapTest.php
index ee1dfc365b8..986d9b1d81a 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/MapTest.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/MapTest.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class MapTest implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/MixedPropertiesAndAdditionalPropertiesClass.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/MixedPropertiesAndAdditionalPropertiesClass.php
index 7c8801f342b..8af27a9c528 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/MixedPropertiesAndAdditionalPropertiesClass.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/MixedPropertiesAndAdditionalPropertiesClass.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class MixedPropertiesAndAdditionalPropertiesClass implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Model200Response.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Model200Response.php
index 1e0117d85fe..d1d79f9fd6c 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Model200Response.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Model200Response.php
@@ -43,6 +43,8 @@ use \ArrayAccess;
  */
 class Model200Response implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelList.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelList.php
index 092b3e51db3..d185af146f4 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelList.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelList.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class ModelList implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelReturn.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelReturn.php
index 2723f3869b5..379acc123a6 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelReturn.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ModelReturn.php
@@ -43,6 +43,8 @@ use \ArrayAccess;
  */
 class ModelReturn implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Name.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Name.php
index ab38479e880..9722713dc26 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Name.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Name.php
@@ -43,6 +43,8 @@ use \ArrayAccess;
  */
 class Name implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/NumberOnly.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/NumberOnly.php
index bb57967f248..3603f9bdd9f 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/NumberOnly.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/NumberOnly.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class NumberOnly implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Order.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Order.php
index 096af928d31..a50b997b635 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Order.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Order.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Order implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php
index 1b05883874d..fe9f255f75c 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Pet implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ReadOnlyFirst.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ReadOnlyFirst.php
index 47efccc34b5..838792fa0c1 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/ReadOnlyFirst.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/ReadOnlyFirst.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class ReadOnlyFirst implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/SpecialModelName.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/SpecialModelName.php
index 514073dbb09..ad2e8394bc7 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/SpecialModelName.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/SpecialModelName.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class SpecialModelName implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Tag.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Tag.php
index d6d2fb62f2c..29578f37802 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/Tag.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/Tag.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class Tag implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/Model/User.php b/samples/client/petstore/php/SwaggerClient-php/lib/Model/User.php
index a69ea12f254..ca36471adce 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/Model/User.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/Model/User.php
@@ -42,6 +42,8 @@ use \ArrayAccess;
  */
 class User implements ArrayAccess
 {
+    const DISCRIMINATOR = null;
+
     /**
       * The original name of the model.
       * @var string
diff --git a/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php b/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php
index 9ba48f42977..fbb2e8b1e45 100644
--- a/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php
+++ b/samples/client/petstore/php/SwaggerClient-php/lib/ObjectSerializer.php
@@ -214,7 +214,7 @@ class ObjectSerializer
      *
      * @return object|array|null an single or an array of $class instances
      */
-    public static function deserialize($data, $class, $httpHeaders = null, $discriminator = null)
+    public static function deserialize($data, $class, $httpHeaders = null)
     {
         if (null === $data) {
             return null;
@@ -225,7 +225,7 @@ class ObjectSerializer
                 $subClass_array = explode(',', $inner, 2);
                 $subClass = $subClass_array[1];
                 foreach ($data as $key => $value) {
-                    $deserialized[$key] = self::deserialize($value, $subClass, null, $discriminator);
+                    $deserialized[$key] = self::deserialize($value, $subClass, null);
                 }
             }
             return $deserialized;
@@ -233,7 +233,7 @@ class ObjectSerializer
             $subClass = substr($class, 0, -2);
             $values = [];
             foreach ($data as $key => $value) {
-                $values[] = self::deserialize($value, $subClass, null, $discriminator);
+                $values[] = self::deserialize($value, $subClass, null);
             }
             return $values;
         } elseif ($class === 'object') {
@@ -271,6 +271,7 @@ class ObjectSerializer
             return $deserialized;
         } else {
             // If a discriminator is defined and points to a valid subclass, use it.
+            $discriminator = $class::DISCRIMINATOR;
             if (!empty($discriminator) && isset($data->{$discriminator}) && is_string($data->{$discriminator})) {
                 $subclass = '\Swagger\Client\Model\\' . $data->{$discriminator};
                 if (is_subclass_of($subclass, $class)) {
@@ -287,7 +288,7 @@ class ObjectSerializer
 
                 $propertyValue = $data->{$instance::attributeMap()[$property]};
                 if (isset($propertyValue)) {
-                    $instance->$propertySetter(self::deserialize($propertyValue, $type, null, $discriminator));
+                    $instance->$propertySetter(self::deserialize($propertyValue, $type, null));
                 }
             }
             return $instance;