Mocking P/Invoke calls?

[Robert]

Hi,

is it possible to mock P/Invoke (Windows API) calls using JustMock commercial edition? I have a helper class which uses a few APIs from advapi32.dll and kernel32.dll to log-on to a remote file share and would like to unit test it and assert whether the right APIs were called with the right parameters.

E.g. the API

[DllImport("advapi32.dll", SetLastError = true)]
>private static extern bool LogonUser(string lpszUsername, string lpszDomain, string lpszPassword, int dwLogonType, int dwLogonProvider, ref IntPtr phToken);

is called in my code and I'd like to assert that the correct user name, domain, password etc. were passed to it.

Regards, Robert

[Ricky]

Hi Robert,

Mocking an extern method directly is not supported.

As a workaround, if you're calling the extern from your own code, you can wrap the call by:

Code:

public static bool InternalLogonUser(string lpszUsername, string lpszDomain, string lpszPassword, int dwLogonType, int dwLogonProvider, ref IntPtr phToken)
{
    return LogonUser(lpszUsername, lpszDomain, lpszPassword, dwLogonType, dwLogonProvider, ref phToken);
}

And mock the behavior on the wrapper call.

Should you have anymore questions please don't hesitate to write us back.

Kind Regards,
Ricky
the Telerik team

[Robert]

Ok, thanks. Are there any plans to support this in the future, or is it too exotic?

Regards, Robert

[Ricky]

Hi Robert,

Thanks again for your reply. I have already included that into our product backlog and we would love to have that support in JustMock. However, due to some technical issues with P/Invoke and profiling, it is not possible to intercept such calls at the moment.

Kind regards,
Ricky
the Telerik team