如何模拟/单元测试嵌套函数

I have a function which is getting called inside other function.

send_api.go

 function *send_api*(client *http.Client,url string) map[string]string,error {
    //send api request and parse the response and return the dict 

    return dictmap
    for eg:{apple fruit}       
}

Then this function is getting called in main() function

func *main()*{

  getmap :=send_api(client *http.Client,"test.com")
 }

good.go

func *get_dict_key*(key string) string,error {
   value,ok := get_map[key]
   if !ok {
          return fmt.Errorf("value is nil")
   }
   return value ,nil    
 }

function *good*(client *http.client, key string) {
 //get a dictionary value
 dcmap,err := get_dict_key("apple")
 if err != nil {
  panic(err)
  }
 value := dcmap[key]

 //use the value to do other processing
 }

unit_test

  func Test_good(t *testing.T) {
      Convey("AND quadra and conusl dcs are mapped",t, func() {
          mockResponses := send mock GET request to the URL and receive a response{"apple":"fruit"}
        }
        server, client := tools.TestClientServer(&mockResponses)
        defer server.Close()
        getMap := send_api(client.HTTPClient, "http://test")
        //At this point getMAP has value {'apple' 'fruit'}
        **q1.How to pass getMap value inside this get_dict_fkey function during testing?**
        value := get_dict_key("apple")
        good(client,"apple") #error:(value is nil)

Q1. **q1.How to pass getMap value inside this get_dict_function during testing?*

Any pointer would be helpful?

Assuming you are facing difficulty to mock http.Client, I would like to suggest following options.

1. Refactor the code

You need to refactor the code in such a way that you can pass the mockable dependencies to function that you would like to test.

For example,

Refactor func send_api(client *http.Client,url string) map[string]string,error so that it does api request and getting/parsing data, but call another function from it, which does the further processing (that actually you would like to test and not the http.Client part).

But, with this approach, you may not be able to test end to end flow. But you can test those functions separately.

2. Mock http.Client

Again, you may need to refactor your code. Some related article can be found here

Update: Recommending to watch justforfunc #16: unit testing HTTP servers