Error using protocol ssh://[user@]host.xz[:port]/path/to/repo.git/

[Hodkinson]

elm $ elm-install -t
/Users/j/.nvm/versions/node/v7.10.0/lib/node_modules/elm-github-install/scripts/dist-1.6.1/elm-install-1.6.1-osx/lib/vendor/ruby/2.2.0/gems/contracts-0.16.0/lib/contracts.rb:46:in `block in <class:Contract>': Contract violation for return value: (ReturnContractError)
        Expected: ElmInstall::Type,
        Actual: nil
        Value guarded in: ElmInstall::Identifier::uri_type
        With Contract: String, ElmInstall::Branch => ElmInstall::Type
        At: /Users/j/.nvm/versions/node/v7.10.0/lib/node_modules/elm-github-install/scripts/dist-1.6.1/elm-install-1.6.1-osx/lib/vendor/ruby/2.2.0/gems/elm_install-1.6.1/lib/elm_install/identifier.rb:116 

[Hodkinson]

Some more detail: if using ssh string like git@bitbucket.server.com:8999/elm/repo.git, the port is ignored.