package namesgenerator import ( "testing" ) type FalseChecker struct{} func (n *FalseChecker) Exists(name string) bool { return false } type TrueChecker struct{} func (n *TrueChecker) Exists(name string) bool { return true } func TestGenerateRandomName(t *testing.T) { if _, err := GenerateRandomName(&FalseChecker{}); err != nil { t.Error(err) } if _, err := GenerateRandomName(&TrueChecker{}); err == nil { t.Error("An error was expected") } }