Add test case for host.go, which contains type `IP`, `HostAddress`, `IPAddress` and function `ConvertAddress`, `ConvertIP`, `ConvertIPFromString`, `ConvertIPAddress`.
Add test case for host.go, which contains type `IP`, `HostAddress`, `IPAddress` and function `ConvertAddress`, `ConvertIP`, `ConvertIPFromString`, `ConvertIPAddress`.

raincious/trap,raincious/trap,raincious/trap,raincious/trap