support nil pointer and pointer of pointer in SetResult and SetError(i…

…mroc#139)

internal/util/util.go

@@ -20,11 +20,29 @@ func IsXMLType(ct string) bool {
 
 // GetPointer return the pointer of the interface.
 func GetPointer(v interface{}) interface{} {
-	vv := reflect.ValueOf(v)
-	if vv.Kind() == reflect.Ptr {
-		return v
+	t := reflect.TypeOf(v)
+	if t.Kind() == reflect.Ptr {
+		if tt := t.Elem(); tt.Kind() == reflect.Ptr { // pointer of pointer
+			if tt.Elem().Kind() == reflect.Ptr {
+				panic("pointer of pointer of pointer is not supported")
+			}
+			el := reflect.ValueOf(v).Elem()
+			if el.IsZero() {
+				vv := reflect.New(tt.Elem())
+				el.Set(vv)
+				return vv.Interface()
+			} else {
+				return el.Interface()
+			}
+		} else {
+			if reflect.ValueOf(v).IsZero() {
+				vv := reflect.New(t.Elem())
+				return vv.Interface()
+			}
+			return v
+		}
 	}
-	return reflect.New(vv.Type()).Interface()
+	return reflect.New(t).Interface()
 }
 
 // GetType return the underlying type.

request_test.go

@@ -359,6 +359,26 @@ func TestSetBodyMarshal(t *testing.T) {
 	}
 }
 
+func TestSetResult(t *testing.T) {
+	c := tc()
+	var user *UserInfo
+	url := "/search?username=imroc&type=json"
+
+	resp, err := c.R().SetResult(&user).Get(url)
+	assertSuccess(t, resp, err)
+	tests.AssertEqual(t, "imroc", user.Username)
+
+	user = &UserInfo{}
+	resp, err = c.R().SetResult(user).Get(url)
+	assertSuccess(t, resp, err)
+	tests.AssertEqual(t, "imroc", user.Username)
+
+	user = nil
+	resp, err = c.R().SetResult(user).Get(url)
+	assertSuccess(t, resp, err)
+	tests.AssertEqual(t, "imroc", resp.Result().(*UserInfo).Username)
+}
+
 func TestSetBody(t *testing.T) {
 	body := "hello"
 	fn := func() (io.ReadCloser, error) {