Consider the following example ssh config:

Host example.com
    Hostname ssh.example.com

When openssh is used to connect to example.com through a non-default port, it will properly honor the non-default port and only replace the hostname with ssh.example.com, e.g.:

$ ssh -p 2222 example.com

This will connect to ssh.example.com via port 2222.

Also, using git to clone the url ssh://git@example.com:2222/my-repo will properly handle this the expected way.

The same URL however will cause go-git to unexpectedly switch to port 22. This happens in doGetHostWithPortFromSSHConfig, which uses DefaultSSHConfig.Get to retrieve the user config port. This will however not find a match in the config (as there is no Port for the host) and thus return the default value 22 for it, causing the unexpected port override.

To fix this, a change in the dependent https://github.com/kevinburke/ssh_config library is required, as it's currently not possible to check if a value exists, which is needed to decide if the port should be overridden or not. I'll link the issue that I'm going to create in the library here later. EDIT here it is

Another inconsistency that I found in the same function is that doGetHostWithPortFromSSHConfig will ignore Port in case no Hostname is configured. My understanding (without having it verified) of the ssh config is that you should be able to override the port without overriding the hostname.