package integers import ( "fmt" "testing" ) func TestAdder(t *testing.T) { sum := Add(2, 2) expected := 4 if sum != expected { t.Errorf("Expected '%d', but got '%d'", expected, sum) } } // If your code changes so that the example is no longer valid, your build will fail. func ExampleAdd() { sum := Add(1, 5) fmt.Println(sum) // Output: 6 }