Golang unit test for panic scenario

user_test.go

func TestUserFail(t *testing.T) {

	func() {
		defer func() {
			if r := recover(); r == nil {
				t.Errorf("TestUserFail should have panicked!")
			}
		}()
		// This function should cause a panic 
		CreateUser(12, "hello")
	}()

}

If I were you I wouldn't break the natural flow of the code under test, and do it like this:

func TestPanic(t *testing.T) {
    // No need to check whether `recover()` is nil. Just turn off the panic.
    defer func() { recover() }()

    OtherFunctionThatPanics()

    // Never reaches here if `OtherFunctionThatPanics` panics.
    t.Errorf("did not panic")
}

For a more general solution, you can also do it like this:

func TestPanic(t *testing.T) {
    shouldPanic(t, OtherFunctionThatPanics)
}

func shouldPanic(t *testing.T, f func()) {
    defer func() { recover() }()
    f()
    t.Errorf("should have panicked")
}