diff --git a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Body2.php b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Body2.php
index 87f5415a615..11705bc054d 100644
--- a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Body2.php
+++ b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Body2.php
@@ -249,7 +249,7 @@ class Body2 implements ModelInterface, ArrayAccess
         $invalidProperties = [];
 
         $allowedValues = $this->getEnumFormStringAllowableValues();
-        if (!is_null($this->container['enum_form_string']) && !in_array($this->container['enum_form_string'], $allowedValues)) {
+        if (!is_null($this->container['enum_form_string']) && !in_array($this->container['enum_form_string'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'enum_form_string', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -257,7 +257,7 @@ class Body2 implements ModelInterface, ArrayAccess
         }
 
         $allowedValues = $this->getEnumQueryDoubleAllowableValues();
-        if (!is_null($this->container['enum_query_double']) && !in_array($this->container['enum_query_double'], $allowedValues)) {
+        if (!is_null($this->container['enum_query_double']) && !in_array($this->container['enum_query_double'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'enum_query_double', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -277,11 +277,11 @@ class Body2 implements ModelInterface, ArrayAccess
     {
 
         $allowedValues = $this->getEnumFormStringAllowableValues();
-        if (!is_null($this->container['enum_form_string']) && !in_array($this->container['enum_form_string'], $allowedValues)) {
+        if (!is_null($this->container['enum_form_string']) && !in_array($this->container['enum_form_string'], $allowedValues, true)) {
             return false;
         }
         $allowedValues = $this->getEnumQueryDoubleAllowableValues();
-        if (!is_null($this->container['enum_query_double']) && !in_array($this->container['enum_query_double'], $allowedValues)) {
+        if (!is_null($this->container['enum_query_double']) && !in_array($this->container['enum_query_double'], $allowedValues, true)) {
             return false;
         }
         return true;
@@ -341,7 +341,7 @@ class Body2 implements ModelInterface, ArrayAccess
     public function setEnumFormString($enum_form_string)
     {
         $allowedValues = $this->getEnumFormStringAllowableValues();
-        if (!is_null($enum_form_string) && !in_array($enum_form_string, $allowedValues)) {
+        if (!is_null($enum_form_string) && !in_array($enum_form_string, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'enum_form_string', must be one of '%s'",
@@ -374,7 +374,7 @@ class Body2 implements ModelInterface, ArrayAccess
     public function setEnumQueryDouble($enum_query_double)
     {
         $allowedValues = $this->getEnumQueryDoubleAllowableValues();
-        if (!is_null($enum_query_double) && !in_array($enum_query_double, $allowedValues)) {
+        if (!is_null($enum_query_double) && !in_array($enum_query_double, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'enum_query_double', must be one of '%s'",
diff --git a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php
index 869d285b752..26a6c705d49 100644
--- a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php
+++ b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumArrays.php
@@ -226,7 +226,7 @@ class EnumArrays implements ModelInterface, ArrayAccess
         $invalidProperties = [];
 
         $allowedValues = $this->getJustSymbolAllowableValues();
-        if (!is_null($this->container['just_symbol']) && !in_array($this->container['just_symbol'], $allowedValues)) {
+        if (!is_null($this->container['just_symbol']) && !in_array($this->container['just_symbol'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'just_symbol', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -246,7 +246,7 @@ class EnumArrays implements ModelInterface, ArrayAccess
     {
 
         $allowedValues = $this->getJustSymbolAllowableValues();
-        if (!is_null($this->container['just_symbol']) && !in_array($this->container['just_symbol'], $allowedValues)) {
+        if (!is_null($this->container['just_symbol']) && !in_array($this->container['just_symbol'], $allowedValues, true)) {
             return false;
         }
         return true;
@@ -273,7 +273,7 @@ class EnumArrays implements ModelInterface, ArrayAccess
     public function setJustSymbol($just_symbol)
     {
         $allowedValues = $this->getJustSymbolAllowableValues();
-        if (!is_null($just_symbol) && !in_array($just_symbol, $allowedValues)) {
+        if (!is_null($just_symbol) && !in_array($just_symbol, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'just_symbol', must be one of '%s'",
diff --git a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php
index cb74a40e686..e57642debf2 100644
--- a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php
+++ b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/EnumTest.php
@@ -278,7 +278,7 @@ class EnumTest implements ModelInterface, ArrayAccess
         $invalidProperties = [];
 
         $allowedValues = $this->getEnumStringAllowableValues();
-        if (!is_null($this->container['enum_string']) && !in_array($this->container['enum_string'], $allowedValues)) {
+        if (!is_null($this->container['enum_string']) && !in_array($this->container['enum_string'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'enum_string', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -289,7 +289,7 @@ class EnumTest implements ModelInterface, ArrayAccess
             $invalidProperties[] = "'enum_string_required' can't be null";
         }
         $allowedValues = $this->getEnumStringRequiredAllowableValues();
-        if (!is_null($this->container['enum_string_required']) && !in_array($this->container['enum_string_required'], $allowedValues)) {
+        if (!is_null($this->container['enum_string_required']) && !in_array($this->container['enum_string_required'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'enum_string_required', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -297,7 +297,7 @@ class EnumTest implements ModelInterface, ArrayAccess
         }
 
         $allowedValues = $this->getEnumIntegerAllowableValues();
-        if (!is_null($this->container['enum_integer']) && !in_array($this->container['enum_integer'], $allowedValues)) {
+        if (!is_null($this->container['enum_integer']) && !in_array($this->container['enum_integer'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'enum_integer', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -305,7 +305,7 @@ class EnumTest implements ModelInterface, ArrayAccess
         }
 
         $allowedValues = $this->getEnumNumberAllowableValues();
-        if (!is_null($this->container['enum_number']) && !in_array($this->container['enum_number'], $allowedValues)) {
+        if (!is_null($this->container['enum_number']) && !in_array($this->container['enum_number'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'enum_number', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -325,22 +325,22 @@ class EnumTest implements ModelInterface, ArrayAccess
     {
 
         $allowedValues = $this->getEnumStringAllowableValues();
-        if (!is_null($this->container['enum_string']) && !in_array($this->container['enum_string'], $allowedValues)) {
+        if (!is_null($this->container['enum_string']) && !in_array($this->container['enum_string'], $allowedValues, true)) {
             return false;
         }
         if ($this->container['enum_string_required'] === null) {
             return false;
         }
         $allowedValues = $this->getEnumStringRequiredAllowableValues();
-        if (!is_null($this->container['enum_string_required']) && !in_array($this->container['enum_string_required'], $allowedValues)) {
+        if (!is_null($this->container['enum_string_required']) && !in_array($this->container['enum_string_required'], $allowedValues, true)) {
             return false;
         }
         $allowedValues = $this->getEnumIntegerAllowableValues();
-        if (!is_null($this->container['enum_integer']) && !in_array($this->container['enum_integer'], $allowedValues)) {
+        if (!is_null($this->container['enum_integer']) && !in_array($this->container['enum_integer'], $allowedValues, true)) {
             return false;
         }
         $allowedValues = $this->getEnumNumberAllowableValues();
-        if (!is_null($this->container['enum_number']) && !in_array($this->container['enum_number'], $allowedValues)) {
+        if (!is_null($this->container['enum_number']) && !in_array($this->container['enum_number'], $allowedValues, true)) {
             return false;
         }
         return true;
@@ -367,7 +367,7 @@ class EnumTest implements ModelInterface, ArrayAccess
     public function setEnumString($enum_string)
     {
         $allowedValues = $this->getEnumStringAllowableValues();
-        if (!is_null($enum_string) && !in_array($enum_string, $allowedValues)) {
+        if (!is_null($enum_string) && !in_array($enum_string, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'enum_string', must be one of '%s'",
@@ -400,7 +400,7 @@ class EnumTest implements ModelInterface, ArrayAccess
     public function setEnumStringRequired($enum_string_required)
     {
         $allowedValues = $this->getEnumStringRequiredAllowableValues();
-        if (!in_array($enum_string_required, $allowedValues)) {
+        if (!in_array($enum_string_required, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'enum_string_required', must be one of '%s'",
@@ -433,7 +433,7 @@ class EnumTest implements ModelInterface, ArrayAccess
     public function setEnumInteger($enum_integer)
     {
         $allowedValues = $this->getEnumIntegerAllowableValues();
-        if (!is_null($enum_integer) && !in_array($enum_integer, $allowedValues)) {
+        if (!is_null($enum_integer) && !in_array($enum_integer, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'enum_integer', must be one of '%s'",
@@ -466,7 +466,7 @@ class EnumTest implements ModelInterface, ArrayAccess
     public function setEnumNumber($enum_number)
     {
         $allowedValues = $this->getEnumNumberAllowableValues();
-        if (!is_null($enum_number) && !in_array($enum_number, $allowedValues)) {
+        if (!is_null($enum_number) && !in_array($enum_number, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'enum_number', must be one of '%s'",
diff --git a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Order.php b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Order.php
index 95ea07a494c..a5dfe109abb 100644
--- a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Order.php
+++ b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Order.php
@@ -237,7 +237,7 @@ class Order implements ModelInterface, ArrayAccess
         $invalidProperties = [];
 
         $allowedValues = $this->getStatusAllowableValues();
-        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues)) {
+        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'status', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -257,7 +257,7 @@ class Order implements ModelInterface, ArrayAccess
     {
 
         $allowedValues = $this->getStatusAllowableValues();
-        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues)) {
+        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues, true)) {
             return false;
         }
         return true;
@@ -380,7 +380,7 @@ class Order implements ModelInterface, ArrayAccess
     public function setStatus($status)
     {
         $allowedValues = $this->getStatusAllowableValues();
-        if (!is_null($status) && !in_array($status, $allowedValues)) {
+        if (!is_null($status) && !in_array($status, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'status', must be one of '%s'",
diff --git a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php
index f2b9b15b013..3ad44bb0605 100644
--- a/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php
+++ b/samples/openapi3/client/petstore/php/SwaggerClient-php/lib/Model/Pet.php
@@ -243,7 +243,7 @@ class Pet implements ModelInterface, ArrayAccess
             $invalidProperties[] = "'photo_urls' can't be null";
         }
         $allowedValues = $this->getStatusAllowableValues();
-        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues)) {
+        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues, true)) {
             $invalidProperties[] = sprintf(
                 "invalid value for 'status', must be one of '%s'",
                 implode("', '", $allowedValues)
@@ -269,7 +269,7 @@ class Pet implements ModelInterface, ArrayAccess
             return false;
         }
         $allowedValues = $this->getStatusAllowableValues();
-        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues)) {
+        if (!is_null($this->container['status']) && !in_array($this->container['status'], $allowedValues, true)) {
             return false;
         }
         return true;
@@ -416,7 +416,7 @@ class Pet implements ModelInterface, ArrayAccess
     public function setStatus($status)
     {
         $allowedValues = $this->getStatusAllowableValues();
-        if (!is_null($status) && !in_array($status, $allowedValues)) {
+        if (!is_null($status) && !in_array($status, $allowedValues, true)) {
             throw new \InvalidArgumentException(
                 sprintf(
                     "Invalid value for 'status', must be one of '%s'",