From a6bf956df5bd0b5eae0b7f70c1e6c044845eb798 Mon Sep 17 00:00:00 2001
From: William Cheng <wing328hk@gmail.com>
Date: Thu, 4 Jun 2020 11:33:21 +0800
Subject: [PATCH] [Go][Experimental] Support additionalProperties (#6525)

* support additonal properties in go

* support additonal properties marshal in go exp

* update go samples
---
 .../GoClientExperimentalCodegen.java          |  7 +++-
 .../go-experimental/model_simple.mustache     | 37 ++++++++++++++++++-
 ...odels-for-testing-with-http-signature.yaml |  1 +
 .../go-petstore/model_200_response.go         |  1 +
 .../model_additional_properties_any_type.go   | 26 +++++++++++++
 .../model_additional_properties_array.go      |  1 +
 .../model_additional_properties_boolean.go    |  1 +
 .../model_additional_properties_class.go      |  1 +
 .../model_additional_properties_integer.go    |  1 +
 .../model_additional_properties_number.go     |  1 +
 .../model_additional_properties_object.go     |  1 +
 .../model_additional_properties_string.go     |  1 +
 .../go-petstore/model_animal.go               |  1 +
 .../go-petstore/model_api_response.go         |  1 +
 .../model_array_of_array_of_number_only.go    |  1 +
 .../go-petstore/model_array_of_number_only.go |  1 +
 .../go-petstore/model_array_test_.go          |  1 +
 .../go-petstore/model_big_cat.go              |  1 +
 .../go-petstore/model_big_cat_all_of.go       |  1 +
 .../go-petstore/model_capitalization.go       |  1 +
 .../go-experimental/go-petstore/model_cat.go  |  1 +
 .../go-petstore/model_cat_all_of.go           |  1 +
 .../go-petstore/model_category.go             |  1 +
 .../go-petstore/model_class_model.go          |  1 +
 .../go-petstore/model_client.go               |  1 +
 .../go-experimental/go-petstore/model_dog.go  |  1 +
 .../go-petstore/model_dog_all_of.go           |  1 +
 .../go-petstore/model_enum_arrays.go          |  1 +
 .../go-petstore/model_enum_test_.go           |  1 +
 .../go-experimental/go-petstore/model_file.go |  1 +
 .../model_file_schema_test_class.go           |  1 +
 .../go-petstore/model_format_test_.go         |  1 +
 .../go-petstore/model_has_only_read_only.go   |  1 +
 .../go-experimental/go-petstore/model_list.go |  1 +
 .../go-petstore/model_map_test_.go            |  1 +
 ...perties_and_additional_properties_class.go |  1 +
 .../go-experimental/go-petstore/model_name.go |  1 +
 .../go-petstore/model_number_only.go          |  1 +
 .../go-petstore/model_order.go                |  1 +
 .../go-petstore/model_outer_composite.go      |  1 +
 .../go-experimental/go-petstore/model_pet.go  |  1 +
 .../go-petstore/model_read_only_first.go      |  1 +
 .../go-petstore/model_return.go               |  1 +
 .../go-petstore/model_special_model_name.go   |  1 +
 .../go-experimental/go-petstore/model_tag.go  |  1 +
 .../go-petstore/model_type_holder_default.go  |  1 +
 .../go-petstore/model_type_holder_example.go  |  1 +
 .../go-experimental/go-petstore/model_user.go |  1 +
 .../go-petstore/model_xml_item.go             |  1 +
 .../go-petstore/api/openapi.yaml              |  1 +
 .../go-petstore/model_200_response.go         |  1 +
 .../go-petstore/model__special_model_name_.go |  1 +
 .../model_additional_properties_class.go      |  1 +
 .../go-petstore/model_animal.go               |  1 +
 .../go-petstore/model_api_response.go         |  1 +
 .../go-petstore/model_apple.go                |  1 +
 .../go-petstore/model_apple_req.go            |  1 +
 .../model_array_of_array_of_number_only.go    |  1 +
 .../go-petstore/model_array_of_number_only.go |  1 +
 .../go-petstore/model_array_test_.go          |  1 +
 .../go-petstore/model_banana.go               | 26 +++++++++++++
 .../go-petstore/model_banana_req.go           |  1 +
 .../go-petstore/model_capitalization.go       |  1 +
 .../go-experimental/go-petstore/model_cat.go  |  1 +
 .../go-petstore/model_cat_all_of.go           |  1 +
 .../go-petstore/model_category.go             |  1 +
 .../go-petstore/model_class_model.go          |  1 +
 .../go-petstore/model_client.go               |  1 +
 .../go-experimental/go-petstore/model_dog.go  |  1 +
 .../go-petstore/model_dog_all_of.go           |  1 +
 .../go-petstore/model_enum_arrays.go          |  1 +
 .../go-petstore/model_enum_test_.go           |  1 +
 .../go-experimental/go-petstore/model_file.go |  1 +
 .../model_file_schema_test_class.go           |  1 +
 .../go-experimental/go-petstore/model_foo.go  |  1 +
 .../go-petstore/model_format_test_.go         |  1 +
 .../go-petstore/model_has_only_read_only.go   |  1 +
 .../go-petstore/model_health_check_result.go  |  1 +
 .../go-petstore/model_inline_object.go        |  1 +
 .../go-petstore/model_inline_object_1.go      |  1 +
 .../go-petstore/model_inline_object_2.go      |  1 +
 .../go-petstore/model_inline_object_3.go      |  1 +
 .../go-petstore/model_inline_object_4.go      |  1 +
 .../go-petstore/model_inline_object_5.go      |  1 +
 .../model_inline_response_default.go          |  1 +
 .../go-experimental/go-petstore/model_list.go |  1 +
 .../go-petstore/model_map_test_.go            |  1 +
 ...perties_and_additional_properties_class.go |  1 +
 .../go-experimental/go-petstore/model_name.go |  1 +
 .../go-petstore/model_nullable_class.go       | 37 +++++++++++++++++++
 .../go-petstore/model_number_only.go          |  1 +
 .../go-petstore/model_order.go                |  1 +
 .../go-petstore/model_outer_composite.go      |  1 +
 .../go-experimental/go-petstore/model_pet.go  |  1 +
 .../go-petstore/model_read_only_first.go      |  1 +
 .../go-petstore/model_return.go               |  1 +
 .../go-experimental/go-petstore/model_tag.go  |  1 +
 .../go-experimental/go-petstore/model_user.go |  1 +
 .../go-petstore/model_whale.go                |  1 +
 .../go-petstore/model_zebra.go                |  1 +
 .../petstore/go-experimental/model_test.go    | 34 +++++++++++++++++
 101 files changed, 259 insertions(+), 3 deletions(-)
 create mode 100644 samples/openapi3/client/petstore/go-experimental/model_test.go

diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientExperimentalCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientExperimentalCodegen.java
index ddb10684f2a0..b9e9fbedbec2 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientExperimentalCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientExperimentalCodegen.java
@@ -222,9 +222,12 @@ public Map<String, Object> postProcessModels(Map<String, Object> objs) {
                 if (model.anyOf != null && !model.anyOf.isEmpty()) {
                     imports.add(createMapping("import", "fmt"));
                 }
-            }
-
 
+                // add x-additional-properties
+                if ("map[string]map[string]interface{}".equals(model.parent)) {
+                    model.vendorExtensions.put("x-additional-properties", true);
+                }
+            }
         }
         return objs;
     }
diff --git a/modules/openapi-generator/src/main/resources/go-experimental/model_simple.mustache b/modules/openapi-generator/src/main/resources/go-experimental/model_simple.mustache
index 1078787c86dd..c4d8d5f684f3 100644
--- a/modules/openapi-generator/src/main/resources/go-experimental/model_simple.mustache
+++ b/modules/openapi-generator/src/main/resources/go-experimental/model_simple.mustache
@@ -13,8 +13,15 @@ type {{classname}} struct {
 {{/description}}
 	{{name}} {{^required}}{{^isNullable}}*{{/isNullable}}{{/required}}{{{dataType}}} `json:"{{baseName}}{{^required}},omitempty{{/required}}"{{#withXml}} xml:"{{baseName}}{{#isXmlAttribute}},attr{{/isXmlAttribute}}"{{/withXml}}{{#vendorExtensions.x-go-custom-tag}} {{{.}}}{{/vendorExtensions.x-go-custom-tag}}`
 {{/vars}}
+{{#vendorExtensions.x-additional-properties}}
+	AdditionalProperties map[string]interface{}
+{{/vendorExtensions.x-additional-properties}}
 }
 
+{{#vendorExtensions.x-additional-properties}}
+type _{{{classname}}} {{{classname}}}
+
+{{/vendorExtensions.x-additional-properties}}
 // New{{classname}} instantiates a new {{classname}} object
 // This constructor will assign default values to properties that have it defined,
 // and makes sure properties required by API are set, but the set of arguments
@@ -246,7 +253,35 @@ func (o {{classname}}) MarshalJSON() ([]byte, error) {
 	}
 	{{/isNullable}}
 	{{/vars}}
+	{{#vendorExtensions.x-additional-properties}}
+
+	for key, value := range o.AdditionalProperties {
+		toSerialize[key] = value
+	}
+
+	{{/vendorExtensions.x-additional-properties}}
 	return json.Marshal(toSerialize)
 }
 
-{{>nullable_model}}
\ No newline at end of file
+{{#vendorExtensions.x-additional-properties}}
+func (o *{{{classname}}}) UnmarshalJSON(bytes []byte) (err error) {
+	var{{{classname}}} := _{{{classname}}}{}
+
+	if err = json.Unmarshal(bytes, &var{{{classname}}}); err == nil {
+		*o = {{{classname}}}(var{{{classname}}})
+	}
+
+	additionalProperties := make(map[string]interface{})
+
+	if err = json.Unmarshal(bytes, &additionalProperties); err == nil {
+		{{#vars}}
+		delete(additionalProperties, "{{{baseName}}}")
+		{{/vars}}
+		o.AdditionalProperties = additionalProperties
+	}
+
+	return err
+}
+
+{{/vendorExtensions.x-additional-properties}}
+{{>nullable_model}}
diff --git a/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml b/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
index 74598c6ce709..81c4cf697c09 100644
--- a/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml
@@ -1810,6 +1810,7 @@ components:
           type: string
     banana:
       type: object
+      additionalProperties: true
       properties:
         lengthCm:
           type: number
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_200_response.go b/samples/client/petstore/go-experimental/go-petstore/model_200_response.go
index 0eea6ec0447c..c23c13c54c2b 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_200_response.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_200_response.go
@@ -147,3 +147,4 @@ func (v *NullableModel200Response) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_any_type.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_any_type.go
index 9618b3d2a26b..59e7a4dec0ae 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_any_type.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_any_type.go
@@ -16,8 +16,11 @@ import (
 // AdditionalPropertiesAnyType struct for AdditionalPropertiesAnyType
 type AdditionalPropertiesAnyType struct {
 	Name *string `json:"name,omitempty"`
+	AdditionalProperties map[string]interface{}
 }
 
+type _AdditionalPropertiesAnyType AdditionalPropertiesAnyType
+
 // NewAdditionalPropertiesAnyType instantiates a new AdditionalPropertiesAnyType object
 // This constructor will assign default values to properties that have it defined,
 // and makes sure properties required by API are set, but the set of arguments
@@ -72,9 +75,31 @@ func (o AdditionalPropertiesAnyType) MarshalJSON() ([]byte, error) {
 	if o.Name != nil {
 		toSerialize["name"] = o.Name
 	}
+
+	for key, value := range o.AdditionalProperties {
+		toSerialize[key] = value
+	}
+
 	return json.Marshal(toSerialize)
 }
 
+func (o *AdditionalPropertiesAnyType) UnmarshalJSON(bytes []byte) (err error) {
+	varAdditionalPropertiesAnyType := _AdditionalPropertiesAnyType{}
+
+	if err = json.Unmarshal(bytes, &varAdditionalPropertiesAnyType); err == nil {
+		*o = AdditionalPropertiesAnyType(varAdditionalPropertiesAnyType)
+	}
+
+	additionalProperties := make(map[string]interface{})
+
+	if err = json.Unmarshal(bytes, &additionalProperties); err == nil {
+		delete(additionalProperties, "name")
+		o.AdditionalProperties = additionalProperties
+	}
+
+	return err
+}
+
 type NullableAdditionalPropertiesAnyType struct {
 	value *AdditionalPropertiesAnyType
 	isSet bool
@@ -111,3 +136,4 @@ func (v *NullableAdditionalPropertiesAnyType) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_array.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_array.go
index 32b38620ad44..7952e9cd56ab 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_array.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_array.go
@@ -111,3 +111,4 @@ func (v *NullableAdditionalPropertiesArray) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_boolean.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_boolean.go
index 098e83c9c42f..f64d9633a475 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_boolean.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_boolean.go
@@ -111,3 +111,4 @@ func (v *NullableAdditionalPropertiesBoolean) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go
index 046e91b90752..d60a6889b740 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go
@@ -471,3 +471,4 @@ func (v *NullableAdditionalPropertiesClass) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_integer.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_integer.go
index dfedb1bc5453..eeb60fc08db4 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_integer.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_integer.go
@@ -111,3 +111,4 @@ func (v *NullableAdditionalPropertiesInteger) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_number.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_number.go
index 10428e020c06..bd385cbe0885 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_number.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_number.go
@@ -111,3 +111,4 @@ func (v *NullableAdditionalPropertiesNumber) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_object.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_object.go
index 6f16a067a4a7..69fb5e310444 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_object.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_object.go
@@ -111,3 +111,4 @@ func (v *NullableAdditionalPropertiesObject) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_string.go b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_string.go
index b3f971dd13a8..54928c3a1c9f 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_string.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_additional_properties_string.go
@@ -111,3 +111,4 @@ func (v *NullableAdditionalPropertiesString) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_animal.go b/samples/client/petstore/go-experimental/go-petstore/model_animal.go
index a1a7f99db9d0..5aa1f60f02fa 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_animal.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_animal.go
@@ -144,3 +144,4 @@ func (v *NullableAnimal) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_api_response.go b/samples/client/petstore/go-experimental/go-petstore/model_api_response.go
index f66dd2b120d1..17bf558d1c9f 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_api_response.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_api_response.go
@@ -183,3 +183,4 @@ func (v *NullableApiResponse) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go b/samples/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go
index 27cc790083db..6b81323ac4dc 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go
@@ -111,3 +111,4 @@ func (v *NullableArrayOfArrayOfNumberOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go b/samples/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go
index ba3cdec1ddea..f43bffc1c874 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go
@@ -111,3 +111,4 @@ func (v *NullableArrayOfNumberOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_array_test_.go b/samples/client/petstore/go-experimental/go-petstore/model_array_test_.go
index bcb080671627..42e2be66d629 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_array_test_.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_array_test_.go
@@ -183,3 +183,4 @@ func (v *NullableArrayTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_big_cat.go b/samples/client/petstore/go-experimental/go-petstore/model_big_cat.go
index f4457f7a83c1..27b8085b241b 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_big_cat.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_big_cat.go
@@ -120,3 +120,4 @@ func (v *NullableBigCat) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_big_cat_all_of.go b/samples/client/petstore/go-experimental/go-petstore/model_big_cat_all_of.go
index f55948719449..6434cd11d7cf 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_big_cat_all_of.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_big_cat_all_of.go
@@ -111,3 +111,4 @@ func (v *NullableBigCatAllOf) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_capitalization.go b/samples/client/petstore/go-experimental/go-petstore/model_capitalization.go
index 782bbab9b1fe..7f2c90863e0c 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_capitalization.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_capitalization.go
@@ -292,3 +292,4 @@ func (v *NullableCapitalization) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_cat.go b/samples/client/petstore/go-experimental/go-petstore/model_cat.go
index 6f7425873cdb..d6573c99bac3 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_cat.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_cat.go
@@ -120,3 +120,4 @@ func (v *NullableCat) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_cat_all_of.go b/samples/client/petstore/go-experimental/go-petstore/model_cat_all_of.go
index 2efc62d2022d..643ba03973f4 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_cat_all_of.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_cat_all_of.go
@@ -111,3 +111,4 @@ func (v *NullableCatAllOf) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_category.go b/samples/client/petstore/go-experimental/go-petstore/model_category.go
index e00cc7ba84bc..0c4628895331 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_category.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_category.go
@@ -142,3 +142,4 @@ func (v *NullableCategory) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_class_model.go b/samples/client/petstore/go-experimental/go-petstore/model_class_model.go
index 5213ad9d8791..7236de0ee071 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_class_model.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_class_model.go
@@ -111,3 +111,4 @@ func (v *NullableClassModel) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_client.go b/samples/client/petstore/go-experimental/go-petstore/model_client.go
index d1b9ffcc2876..edfdde067ef6 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_client.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_client.go
@@ -111,3 +111,4 @@ func (v *NullableClient) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_dog.go b/samples/client/petstore/go-experimental/go-petstore/model_dog.go
index 12a5bee4876f..ebbedeec53e8 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_dog.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_dog.go
@@ -120,3 +120,4 @@ func (v *NullableDog) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_dog_all_of.go b/samples/client/petstore/go-experimental/go-petstore/model_dog_all_of.go
index a5a791e50f0a..c13aa2b2cd57 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_dog_all_of.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_dog_all_of.go
@@ -111,3 +111,4 @@ func (v *NullableDogAllOf) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_enum_arrays.go b/samples/client/petstore/go-experimental/go-petstore/model_enum_arrays.go
index 1fbadb34e715..b18984ce7306 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_enum_arrays.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_enum_arrays.go
@@ -147,3 +147,4 @@ func (v *NullableEnumArrays) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_enum_test_.go b/samples/client/petstore/go-experimental/go-petstore/model_enum_test_.go
index 852dd860739c..c39d045e5a6b 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_enum_test_.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_enum_test_.go
@@ -248,3 +248,4 @@ func (v *NullableEnumTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_file.go b/samples/client/petstore/go-experimental/go-petstore/model_file.go
index d7a50dc683a7..43ec19f86383 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_file.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_file.go
@@ -112,3 +112,4 @@ func (v *NullableFile) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go b/samples/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go
index 887cd35c752f..626a3765173a 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go
@@ -147,3 +147,4 @@ func (v *NullableFileSchemaTestClass) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_format_test_.go b/samples/client/petstore/go-experimental/go-petstore/model_format_test_.go
index dbccde98dc46..aa1889aedda1 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_format_test_.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_format_test_.go
@@ -553,3 +553,4 @@ func (v *NullableFormatTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go b/samples/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go
index 0aa39e6de8ca..3400c73dca67 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go
@@ -147,3 +147,4 @@ func (v *NullableHasOnlyReadOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_list.go b/samples/client/petstore/go-experimental/go-petstore/model_list.go
index 7966d7b337ca..f49afaa71f33 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_list.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_list.go
@@ -111,3 +111,4 @@ func (v *NullableList) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_map_test_.go b/samples/client/petstore/go-experimental/go-petstore/model_map_test_.go
index 42724f8d8758..4fc2c0b47991 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_map_test_.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_map_test_.go
@@ -219,3 +219,4 @@ func (v *NullableMapTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go b/samples/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go
index 21b7cb60ab4c..69cc134169e7 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go
@@ -184,3 +184,4 @@ func (v *NullableMixedPropertiesAndAdditionalPropertiesClass) UnmarshalJSON(src
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_name.go b/samples/client/petstore/go-experimental/go-petstore/model_name.go
index f910dc37c0c4..82e49591874b 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_name.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_name.go
@@ -212,3 +212,4 @@ func (v *NullableName) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_number_only.go b/samples/client/petstore/go-experimental/go-petstore/model_number_only.go
index 6307b2871e96..efa8b66a5bcc 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_number_only.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_number_only.go
@@ -111,3 +111,4 @@ func (v *NullableNumberOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_order.go b/samples/client/petstore/go-experimental/go-petstore/model_order.go
index 797c8e9236f4..b20a14298482 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_order.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_order.go
@@ -297,3 +297,4 @@ func (v *NullableOrder) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_outer_composite.go b/samples/client/petstore/go-experimental/go-petstore/model_outer_composite.go
index 88049de0dac0..9a76c753b644 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_outer_composite.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_outer_composite.go
@@ -183,3 +183,4 @@ func (v *NullableOuterComposite) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_pet.go b/samples/client/petstore/go-experimental/go-petstore/model_pet.go
index 876af8724d73..8bc4457fc372 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_pet.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_pet.go
@@ -278,3 +278,4 @@ func (v *NullablePet) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_read_only_first.go b/samples/client/petstore/go-experimental/go-petstore/model_read_only_first.go
index af6291b4c820..dd00212c1d04 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_read_only_first.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_read_only_first.go
@@ -147,3 +147,4 @@ func (v *NullableReadOnlyFirst) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_return.go b/samples/client/petstore/go-experimental/go-petstore/model_return.go
index e6350da030cb..2ed729e12eca 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_return.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_return.go
@@ -111,3 +111,4 @@ func (v *NullableReturn) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_special_model_name.go b/samples/client/petstore/go-experimental/go-petstore/model_special_model_name.go
index e50eb5d32d14..bbef383b796a 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_special_model_name.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_special_model_name.go
@@ -111,3 +111,4 @@ func (v *NullableSpecialModelName) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_tag.go b/samples/client/petstore/go-experimental/go-petstore/model_tag.go
index 0f8157a6b7a8..99135ba946be 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_tag.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_tag.go
@@ -147,3 +147,4 @@ func (v *NullableTag) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_type_holder_default.go b/samples/client/petstore/go-experimental/go-petstore/model_type_holder_default.go
index 3ff4e709be14..d45748bf769e 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_type_holder_default.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_type_holder_default.go
@@ -224,3 +224,4 @@ func (v *NullableTypeHolderDefault) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_type_holder_example.go b/samples/client/petstore/go-experimental/go-petstore/model_type_holder_example.go
index 4996f734edc5..3f74c433f715 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_type_holder_example.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_type_holder_example.go
@@ -249,3 +249,4 @@ func (v *NullableTypeHolderExample) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_user.go b/samples/client/petstore/go-experimental/go-petstore/model_user.go
index 29f2e3f26526..7dff4e8b36b9 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_user.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_user.go
@@ -364,3 +364,4 @@ func (v *NullableUser) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/client/petstore/go-experimental/go-petstore/model_xml_item.go b/samples/client/petstore/go-experimental/go-petstore/model_xml_item.go
index 1d78601f0609..8bf7f3ef7073 100644
--- a/samples/client/petstore/go-experimental/go-petstore/model_xml_item.go
+++ b/samples/client/petstore/go-experimental/go-petstore/model_xml_item.go
@@ -1119,3 +1119,4 @@ func (v *NullableXmlItem) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/api/openapi.yaml b/samples/openapi3/client/petstore/go-experimental/go-petstore/api/openapi.yaml
index f7bec5630719..7e77947b7a74 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/api/openapi.yaml
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/api/openapi.yaml
@@ -1925,6 +1925,7 @@ components:
           type: string
       type: object
     banana:
+      additionalProperties: true
       properties:
         lengthCm:
           type: number
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_200_response.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_200_response.go
index 0eea6ec0447c..c23c13c54c2b 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_200_response.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_200_response.go
@@ -147,3 +147,4 @@ func (v *NullableModel200Response) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model__special_model_name_.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model__special_model_name_.go
index e50eb5d32d14..bbef383b796a 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model__special_model_name_.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model__special_model_name_.go
@@ -111,3 +111,4 @@ func (v *NullableSpecialModelName) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go
index 941f00027dbb..2ac0b72cfa23 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_additional_properties_class.go
@@ -147,3 +147,4 @@ func (v *NullableAdditionalPropertiesClass) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_animal.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_animal.go
index a1a7f99db9d0..5aa1f60f02fa 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_animal.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_animal.go
@@ -144,3 +144,4 @@ func (v *NullableAnimal) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_api_response.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_api_response.go
index f66dd2b120d1..17bf558d1c9f 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_api_response.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_api_response.go
@@ -183,3 +183,4 @@ func (v *NullableApiResponse) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple.go
index d6800b1ad0aa..97b0b94f3e9e 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple.go
@@ -111,3 +111,4 @@ func (v *NullableApple) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple_req.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple_req.go
index f5f4cbad71e0..3879864cf14e 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple_req.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_apple_req.go
@@ -140,3 +140,4 @@ func (v *NullableAppleReq) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go
index 27cc790083db..6b81323ac4dc 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_array_of_number_only.go
@@ -111,3 +111,4 @@ func (v *NullableArrayOfArrayOfNumberOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go
index ba3cdec1ddea..f43bffc1c874 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_of_number_only.go
@@ -111,3 +111,4 @@ func (v *NullableArrayOfNumberOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_test_.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_test_.go
index bcb080671627..42e2be66d629 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_test_.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_array_test_.go
@@ -183,3 +183,4 @@ func (v *NullableArrayTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana.go
index a4fb1e386409..f375a8b8f9c0 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana.go
@@ -16,8 +16,11 @@ import (
 // Banana struct for Banana
 type Banana struct {
 	LengthCm *float32 `json:"lengthCm,omitempty"`
+	AdditionalProperties map[string]interface{}
 }
 
+type _Banana Banana
+
 // NewBanana instantiates a new Banana object
 // This constructor will assign default values to properties that have it defined,
 // and makes sure properties required by API are set, but the set of arguments
@@ -72,9 +75,31 @@ func (o Banana) MarshalJSON() ([]byte, error) {
 	if o.LengthCm != nil {
 		toSerialize["lengthCm"] = o.LengthCm
 	}
+
+	for key, value := range o.AdditionalProperties {
+		toSerialize[key] = value
+	}
+
 	return json.Marshal(toSerialize)
 }
 
+func (o *Banana) UnmarshalJSON(bytes []byte) (err error) {
+	varBanana := _Banana{}
+
+	if err = json.Unmarshal(bytes, &varBanana); err == nil {
+		*o = Banana(varBanana)
+	}
+
+	additionalProperties := make(map[string]interface{})
+
+	if err = json.Unmarshal(bytes, &additionalProperties); err == nil {
+		delete(additionalProperties, "lengthCm")
+		o.AdditionalProperties = additionalProperties
+	}
+
+	return err
+}
+
 type NullableBanana struct {
 	value *Banana
 	isSet bool
@@ -111,3 +136,4 @@ func (v *NullableBanana) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana_req.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana_req.go
index eb0d40c61d96..ed874ef2e6fd 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana_req.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_banana_req.go
@@ -140,3 +140,4 @@ func (v *NullableBananaReq) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_capitalization.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_capitalization.go
index 782bbab9b1fe..7f2c90863e0c 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_capitalization.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_capitalization.go
@@ -292,3 +292,4 @@ func (v *NullableCapitalization) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat.go
index 6f7425873cdb..d6573c99bac3 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat.go
@@ -120,3 +120,4 @@ func (v *NullableCat) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat_all_of.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat_all_of.go
index 2efc62d2022d..643ba03973f4 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat_all_of.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_cat_all_of.go
@@ -111,3 +111,4 @@ func (v *NullableCatAllOf) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_category.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_category.go
index e00cc7ba84bc..0c4628895331 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_category.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_category.go
@@ -142,3 +142,4 @@ func (v *NullableCategory) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_class_model.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_class_model.go
index 5213ad9d8791..7236de0ee071 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_class_model.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_class_model.go
@@ -111,3 +111,4 @@ func (v *NullableClassModel) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_client.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_client.go
index d1b9ffcc2876..edfdde067ef6 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_client.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_client.go
@@ -111,3 +111,4 @@ func (v *NullableClient) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog.go
index 12a5bee4876f..ebbedeec53e8 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog.go
@@ -120,3 +120,4 @@ func (v *NullableDog) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog_all_of.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog_all_of.go
index a5a791e50f0a..c13aa2b2cd57 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog_all_of.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_dog_all_of.go
@@ -111,3 +111,4 @@ func (v *NullableDogAllOf) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_arrays.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_arrays.go
index 1fbadb34e715..b18984ce7306 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_arrays.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_arrays.go
@@ -147,3 +147,4 @@ func (v *NullableEnumArrays) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_test_.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_test_.go
index f9c20efe677c..d6da2e58bf99 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_test_.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_enum_test_.go
@@ -374,3 +374,4 @@ func (v *NullableEnumTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file.go
index d7a50dc683a7..43ec19f86383 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file.go
@@ -112,3 +112,4 @@ func (v *NullableFile) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go
index 887cd35c752f..626a3765173a 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_file_schema_test_class.go
@@ -147,3 +147,4 @@ func (v *NullableFileSchemaTestClass) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_foo.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_foo.go
index 825b2761c1c1..723deec46aa4 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_foo.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_foo.go
@@ -115,3 +115,4 @@ func (v *NullableFoo) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_format_test_.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_format_test_.go
index bcc0289a0914..67f0c80c72e5 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_format_test_.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_format_test_.go
@@ -591,3 +591,4 @@ func (v *NullableFormatTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go
index 0aa39e6de8ca..3400c73dca67 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_has_only_read_only.go
@@ -147,3 +147,4 @@ func (v *NullableHasOnlyReadOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_health_check_result.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_health_check_result.go
index af5a5b94a1ec..70874db5605e 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_health_check_result.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_health_check_result.go
@@ -121,3 +121,4 @@ func (v *NullableHealthCheckResult) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object.go
index ec6a571e8eb5..35df941a0d62 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object.go
@@ -149,3 +149,4 @@ func (v *NullableInlineObject) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_1.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_1.go
index d95ad59790ab..a400eda20e36 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_1.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_1.go
@@ -150,3 +150,4 @@ func (v *NullableInlineObject1) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_2.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_2.go
index d3029a8e77b0..a80ba9b9e5c5 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_2.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_2.go
@@ -153,3 +153,4 @@ func (v *NullableInlineObject2) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_3.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_3.go
index c51c19956f50..9dcc233d034d 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_3.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_3.go
@@ -567,3 +567,4 @@ func (v *NullableInlineObject3) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_4.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_4.go
index b4fcf5fa1f0b..783556ef23cc 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_4.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_4.go
@@ -135,3 +135,4 @@ func (v *NullableInlineObject4) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_5.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_5.go
index 974844007a74..055f4ff8fe28 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_5.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_object_5.go
@@ -143,3 +143,4 @@ func (v *NullableInlineObject5) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_response_default.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_response_default.go
index 19fb6bcd8a80..3c8ca5deafeb 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_response_default.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_inline_response_default.go
@@ -111,3 +111,4 @@ func (v *NullableInlineResponseDefault) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_list.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_list.go
index 7966d7b337ca..f49afaa71f33 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_list.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_list.go
@@ -111,3 +111,4 @@ func (v *NullableList) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_map_test_.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_map_test_.go
index 42724f8d8758..4fc2c0b47991 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_map_test_.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_map_test_.go
@@ -219,3 +219,4 @@ func (v *NullableMapTest) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go
index 21b7cb60ab4c..69cc134169e7 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_mixed_properties_and_additional_properties_class.go
@@ -184,3 +184,4 @@ func (v *NullableMixedPropertiesAndAdditionalPropertiesClass) UnmarshalJSON(src
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_name.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_name.go
index f910dc37c0c4..82e49591874b 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_name.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_name.go
@@ -212,3 +212,4 @@ func (v *NullableName) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_nullable_class.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_nullable_class.go
index 0f3e7fb3a419..d2eb6062f6e8 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_nullable_class.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_nullable_class.go
@@ -28,8 +28,11 @@ type NullableClass struct {
 	ObjectNullableProp map[string]map[string]interface{} `json:"object_nullable_prop,omitempty"`
 	ObjectAndItemsNullableProp map[string]map[string]interface{} `json:"object_and_items_nullable_prop,omitempty"`
 	ObjectItemsNullable *map[string]map[string]interface{} `json:"object_items_nullable,omitempty"`
+	AdditionalProperties map[string]interface{}
 }
 
+type _NullableClass NullableClass
+
 // NewNullableClass instantiates a new NullableClass object
 // This constructor will assign default values to properties that have it defined,
 // and makes sure properties required by API are set, but the set of arguments
@@ -533,9 +536,42 @@ func (o NullableClass) MarshalJSON() ([]byte, error) {
 	if o.ObjectItemsNullable != nil {
 		toSerialize["object_items_nullable"] = o.ObjectItemsNullable
 	}
+
+	for key, value := range o.AdditionalProperties {
+		toSerialize[key] = value
+	}
+
 	return json.Marshal(toSerialize)
 }
 
+func (o *NullableClass) UnmarshalJSON(bytes []byte) (err error) {
+	varNullableClass := _NullableClass{}
+
+	if err = json.Unmarshal(bytes, &varNullableClass); err == nil {
+		*o = NullableClass(varNullableClass)
+	}
+
+	additionalProperties := make(map[string]interface{})
+
+	if err = json.Unmarshal(bytes, &additionalProperties); err == nil {
+		delete(additionalProperties, "integer_prop")
+		delete(additionalProperties, "number_prop")
+		delete(additionalProperties, "boolean_prop")
+		delete(additionalProperties, "string_prop")
+		delete(additionalProperties, "date_prop")
+		delete(additionalProperties, "datetime_prop")
+		delete(additionalProperties, "array_nullable_prop")
+		delete(additionalProperties, "array_and_items_nullable_prop")
+		delete(additionalProperties, "array_items_nullable")
+		delete(additionalProperties, "object_nullable_prop")
+		delete(additionalProperties, "object_and_items_nullable_prop")
+		delete(additionalProperties, "object_items_nullable")
+		o.AdditionalProperties = additionalProperties
+	}
+
+	return err
+}
+
 type NullableNullableClass struct {
 	value *NullableClass
 	isSet bool
@@ -572,3 +608,4 @@ func (v *NullableNullableClass) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_number_only.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_number_only.go
index 6307b2871e96..efa8b66a5bcc 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_number_only.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_number_only.go
@@ -111,3 +111,4 @@ func (v *NullableNumberOnly) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_order.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_order.go
index 797c8e9236f4..b20a14298482 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_order.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_order.go
@@ -297,3 +297,4 @@ func (v *NullableOrder) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_outer_composite.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_outer_composite.go
index 88049de0dac0..9a76c753b644 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_outer_composite.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_outer_composite.go
@@ -183,3 +183,4 @@ func (v *NullableOuterComposite) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_pet.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_pet.go
index 876af8724d73..8bc4457fc372 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_pet.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_pet.go
@@ -278,3 +278,4 @@ func (v *NullablePet) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_read_only_first.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_read_only_first.go
index af6291b4c820..dd00212c1d04 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_read_only_first.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_read_only_first.go
@@ -147,3 +147,4 @@ func (v *NullableReadOnlyFirst) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_return.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_return.go
index e6350da030cb..2ed729e12eca 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_return.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_return.go
@@ -111,3 +111,4 @@ func (v *NullableReturn) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_tag.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_tag.go
index 0f8157a6b7a8..99135ba946be 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_tag.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_tag.go
@@ -147,3 +147,4 @@ func (v *NullableTag) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_user.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_user.go
index f9824d767f22..ce40d756100f 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_user.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_user.go
@@ -515,3 +515,4 @@ func (v *NullableUser) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_whale.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_whale.go
index faeb81870214..0b81bcfa7ad4 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_whale.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_whale.go
@@ -176,3 +176,4 @@ func (v *NullableWhale) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_zebra.go b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_zebra.go
index b28b9d7d1dbe..82854d088349 100644
--- a/samples/openapi3/client/petstore/go-experimental/go-petstore/model_zebra.go
+++ b/samples/openapi3/client/petstore/go-experimental/go-petstore/model_zebra.go
@@ -140,3 +140,4 @@ func (v *NullableZebra) UnmarshalJSON(src []byte) error {
 	return json.Unmarshal(src, &v.value)
 }
 
+
diff --git a/samples/openapi3/client/petstore/go-experimental/model_test.go b/samples/openapi3/client/petstore/go-experimental/model_test.go
new file mode 100644
index 000000000000..46012d009e62
--- /dev/null
+++ b/samples/openapi3/client/petstore/go-experimental/model_test.go
@@ -0,0 +1,34 @@
+package main
+
+import (
+	"testing"
+    "encoding/json"
+	"github.com/stretchr/testify/assert"
+	sw "./go-petstore"
+)
+
+func TestBanana(t *testing.T) {
+    assert := assert.New(t)
+
+    lengthCm := float32(2.3)
+    lengthCm2 := float32(2.4)
+    newBanana := (sw.Banana{LengthCm: &lengthCm})
+    newBanana.LengthCm = &lengthCm2
+    assert.Equal(newBanana.LengthCm, &lengthCm2, "Banana LengthCm should be equal")
+
+    // test additioanl properties
+    jsonBanana:= `{"fruits":["apple","peach"],"lengthCm":3.1}`
+    jsonMap := make(map[string]interface{})
+    json.Unmarshal([]byte(jsonBanana), &jsonMap)
+
+    newBanana2 := (sw.Banana{})
+    lengthCm3 := float32(3.1)
+    json.Unmarshal([]byte(jsonBanana), &newBanana2)
+    assert.Equal(newBanana2.LengthCm, &lengthCm3, "Banana2 LengthCm should be equal")
+    assert.Equal(newBanana2.AdditionalProperties["fruits"], jsonMap["fruits"], "Banana2 AdditonalProperties should be equal")
+
+    newBanana2Json, _ := json.Marshal(newBanana2)
+    assert.Equal(string(newBanana2Json), jsonBanana, "Banana2 JSON string should be equal")
+
+}
+