A travis run for native macOS has recently been added, but it required a hacky cd workaround. Someone experienced with macOS on travis (or a lot of time) might want to debug this workaround and either remove it or document and wrap it. See https://github.com/bitcoin/bitcoin/pull/16597/files#r336052676 for context.