c# - RestSharp Unit Test NUnit Moq RestResponse null reference exception -

i'm having challenges trying use moq restsharp. maybe it's misunderstanding of moq reason keep on getting null reference exception when trying mock restresponse.

here unit test.

    [test]     public void getall_method_throws_exception_if_response_data_is_null()     {         var restclient = new mock<irestclient>();          restclient.setup(x => x.execute(it.isany<irestrequest>()))             .returns(new restresponse<rootobjectlist>             {                 statuscode = httpstatuscode.ok,                 content = null             } );          var client = new incidentrestclient(restclient.object);          assert.throws<exception>(() => client.getall());     } 

here implementation:

public class incidentrestclient : iincidentrestclient {     private readonly irestclient client;     private readonly string url = "some url here";      public incidentrestclient()     {         client = new restclient { baseurl = new uri(url) };     }      public rootobjectlist  getall()     {         var request = new restrequest("api/now/table/incident", method.get) { requestformat = dataformat.json };         request.onbeforedeserialization = resp => { resp.contenttype = "application/json"; };          irestresponse<rootobjectlist> response = client.execute<rootobjectlist>(request);          if (response.data == null)             throw new exception(response.errorexception.tostring());          return response.data;     } } 

for reason response object null. i'm mocking return object incorrectly?

for disclosure purposes, assuming incidentrestclient has constructor takes irestclient instance parameter , uses set client member.

it looks like, in test, running setup different overload of execute 1 using. instead of:

.setup(x => x.execute( 

try:

.setup(x => x.execute<rootobjectlist>(