ZSH OpenSSH 7.3p1 Hosts Completion

# Custom hosts completion from included SSH configs:

zstyle -e ':completion:*:hosts' hosts 'reply=(
  ${=${=${=${${(f)"$(cat {/etc/ssh_,~/.ssh/known_}hosts(|2)(N) 2>/dev/null)"}%%[#| ]*}//\]:[0-9]*/ }//,/ }//\[/ }
  ${=${(f)"$(cat /etc/hosts(|)(N) <<(ypcat hosts 2>/dev/null))"}%%\#*}
  ${=${${${${(@M)${(f)"$(cat ~/.ssh/config 2>/dev/null)"}:#Host *}#Host }:#*\**}:#*\?*}}
  ${=${${${${(@M)${(f)"$(cat ~/.ssh/config.d/* 2>/dev/null)"}:#Host *}#Host }:#*\**}:#*\?*}}
)'

# The last line above supports reading from files inside a local SSH configuration directory. It pulls
# all configured hosts and allows them to be used for tab completion.