proposal: testing: add assertion methods #52555
Description
It's very common to use packages like testify or is as a set of helper methods that make testing code more readable. The reason behind using packages like that is to avoid writing repetitive code like the following.
func TestAddition(t *testing.T) {
given := 2+4
expected := 4
if given != expected {
t.Errorf("expected %d but %d given", expected, given)
}
}The if statement with the error message can be repeated even a hundred times. That's why we use external libraries to avoid that.
As we have generics in the language, we can make use of it and provide a new method in testing.T and testing.B:
func (t T) Equal[T comparable](expected, given T) {
// comparing
t.Fail()
}
func (t T) Equalf[T comparable](expected, given T, format string, args ...string) {
// comparing
t.Fail()
}The first snipped would be simplified into:
func TestAddition(t *testing.T) {
given := 2+4
expected := 4
t.Equal(expected, given)
}
func TestAddition2(t *testing.T) {
given := 2+4
expected := 4
t.Equalf(expected, given, "math should always work")
}Using generics has a big benefit over using any - we have a compile-time type check.
I know that saving those 2 lines of code doesn't seem to be a big win but please remember that the code may be repeated many times in a single test file.