Fake go client not working as expected

User Experience
1

service rolebinding am trying to create

{
  "apiVersion": "rbac.istio.io/v1alpha1",
  "kind": "ServiceRoleBinding",
  "metadata": {
    "name": "bind-service-viewer"
  },
  "spec": {
    "subjects": [
      {
        "user": "*"
      }
    ],
    "roleRef": {
      "kind": "ServiceRole",
      "name": "service-viewer"
    }
  }
}

Go code for the same

raw, _ := ioutil.ReadFile("./files/def-srb.json")
srb := "istio.io/client-go/pkg/apis/rbac/v1alpha1".ServiceRoleBinding{}
json.Unmarshal(raw, &srb)
return "istio.io/client-go/pkg/clientset/versioned/typed/rbac/v1alpha1".ServiceRoleBindings(ns).Create(&srb)

Test code for the same

func TestCreateSRB (t *testing.T) {
	raw, err := ioutil.ReadFile("./files/def-srb.json")
	if err != nil {
		fmt.Println(err)
	}
	srb := v1alpha1.ServiceRoleBinding{}
	err = json.Unmarshal(raw, &srb)
	if err != nil {
		fmt.Println(err)
	}	
	resp, err := CreateSRBforFunc("test", istioclient.NewSimpleClientset().RbacV1alpha1(), "test-group", "test-fn")
	checkError(err, t)
	if diff := cmp.Diff(&srb, resp); diff != "" {
		t.Errorf("mismatch (-want +got):\n%s", diff)
	}		
}

Test Result

--- FAIL: TestCreateSRB (0.00s)
    ns_test.go:237: mismatch (-want +got):
          &v1alpha1.ServiceRoleBinding{
          	TypeMeta: v1.TypeMeta{Kind: "ServiceRoleBinding", APIVersion: "rbac.istio.io/v1alpha1"},
          	ObjectMeta: v1.ObjectMeta{
          		Name:         "bind-service-viewer",
          		GenerateName: "",
        - 		Namespace:    "",
        + 		Namespace:    "test",
          		SelfLink:     "",
          		UID:          "",
          		... // 11 identical fields
          	},
          	Spec: v1alpha1.ServiceRoleBinding{
          		Subjects: []*v1alpha1.Subject{
          			&{User: "*"},
        + 			s`user:"*" `,
        + 			s`user:"*" `,
        + 			s`user:"*" `,
        + 			s`user:"*" `,
        + 			s`user:"*" `,
        + 			s`user:"*" `,
        + 			s`user:"*" `,
          		},
          		RoleRef: &v1alpha1.RoleRef{Kind: "ServiceRole", Name: "service-viewer"},
          		Mode:    s"ENFORCED",
          		... // 5 identical fields
          	},
          }
FAIL
exit status 1

Not sure why so many user subjects are created