package commons import ( "log" "fmt" "bytes" "encoding/json" "testing" ) func TestJsonPrintError(t *testing.T) { jsonstr := ` { "name": "George", "age": 87, active": "false", "properties": { "one": "two", "three": "four" } } ` var buf bytes.Buffer log.SetOutput(&buf) content := []byte(jsonstr) var data map[string]any err := json.Unmarshal(content, &data) JsonPrintError(err, content) errOut := fmt.Sprintf("%s", buf.String()) if errOut == "" { t.Fatal("should have printed the error") } }