It appears that git 2.16.0 and 2.16.1 have introduced a change which surprises the Jenkins git client plugin. Git 2.16.0 and 2.16.1 on Linux both report "fatal: ssh variant 'simple' does not support setting port" when used in the context of the Jenkins git client plugin. The solution we've accepted into the git client plugin source code is to set the environment variable "GIT_SSH_VARIANT=ssh". That allows the failing case to pass, and does not seem to harm older versions of git. The documentation at https://git-scm.com/docs/git says that GIT_SSH_VARIANT "overrides Git’s autodetection whether GIT_SSH/GIT_SSH_COMMAND/core.sshCommand refer to OpenSSH, plink or tortoiseplink." I haven't seen the same message from Git 2.16.1 for Windows. The Jenkins bug report (https://issues.jenkins-ci.org/browse/JENKINS-49111) describes the user experience. Is the GIT_SSH_VARIANT solution expected to be used by git consumers like the Jenkins git client plugin when passing credential information through environment variables like SSH_ASKPASS? I see "ssh", "plink", and "tortoiseplink" as values of GIT_SSH_VARIANT used in tests, and "auto", "putty", and "simple" used in the source code in addition to "ssh", "plink", and "tortoiseplink". What are the allowed values for GIT_SSH_VARIANT? What is the recommended value so that the Jenkins git client plugin can remain most compatible with previous behavior? No value was assigned previously to GIT_SSH_VARIANT in the Jenkins git client plugin. I was expecting that git would choose "ssh" as the default value for GIT_SSH_VARIANT, rather than apparently choosing "simple". Is this a bug, or is this the new, intentional behavior of git? Thanks, Mark Waite
