Make nullable fix on all vars in Go (#8820)

* Make nullable fix on all vars in Go

This applies the Nullable change to all variables on the model, instead
of just the ones in vars.

* Add sample showing the issue

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientCodegen.java

@@ -17,6 +17,7 @@
 
 package org.openapitools.codegen.languages;
 
+import com.google.common.collect.Iterables;
 import io.swagger.v3.oas.models.media.Schema;
 import io.swagger.v3.oas.models.security.SecurityScheme;
 import org.apache.commons.lang3.StringUtils;
@@ -387,7 +388,7 @@ public class GoClientCodegen extends AbstractGoCodegen {
                     continue;
                 }
 
-                for (CodegenProperty param : model.vars) {
+                for (CodegenProperty param : Iterables.concat(model.vars, model.allVars, model.requiredVars, model.optionalVars)) {
                     param.vendorExtensions.put("x-go-base-type", param.dataType);
                     if (!param.isNullable || param.isMap || param.isArray ||
                             param.isFreeFormObject || param.isAnyType) {

modules/openapi-generator/src/test/resources/3_0/petstore-with-fake-endpoints-models-for-testing-with-http-signature.yaml

@@ -1752,6 +1752,7 @@ components:
         boolean_prop:
           type: boolean
           nullable: true
+          default: false
         string_prop:
           type: string
           nullable: true

samples/openapi3/client/petstore/go/go-petstore/api/openapi.yaml

@@ -1868,6 +1868,7 @@ components:
           nullable: true
           type: number
         boolean_prop:
+          default: false
           nullable: true
           type: boolean
         string_prop:

samples/openapi3/client/petstore/go/go-petstore/docs/NullableClass.md

@@ -6,7 +6,7 @@ Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
 **IntegerProp** | Pointer to **NullableInt32** |  | [optional] 
 **NumberProp** | Pointer to **NullableFloat32** |  | [optional] 
-**BooleanProp** | Pointer to **NullableBool** |  | [optional] 
+**BooleanProp** | Pointer to **NullableBool** |  | [optional] [default to false]
 **StringProp** | Pointer to **NullableString** |  | [optional] 
 **DateProp** | Pointer to **NullableString** |  | [optional] 
 **DatetimeProp** | Pointer to **NullableTime** |  | [optional] 

samples/openapi3/client/petstore/go/go-petstore/model_nullable_class.go

@@ -37,6 +37,8 @@ type NullableClass struct {
 // will change when the set of required properties is changed
 func NewNullableClass() *NullableClass {
 	this := NullableClass{}
+	var booleanProp bool = false
+	this.BooleanProp = *NewNullableBool(&booleanProp)
 	return &this
 }
 
@@ -45,6 +47,8 @@ func NewNullableClass() *NullableClass {
 // but it doesn't guarantee that properties required by API are set
 func NewNullableClassWithDefaults() *NullableClass {
 	this := NullableClass{}
+	var booleanProp bool = false
+	this.BooleanProp = *NewNullableBool(&booleanProp)
 	return &this
 }