fix(tmux): Import and modify completions from zsh-user

plugins/tmux/tmux.plugin.zsh

@@ -57,12 +57,53 @@ function _build_tmux_alias {
  }"
 }
 
-function _session_completion {
+# ALIAS COMPLETION (Modified from https://github.com/zsh-users/zsh)
+_tmux-attach-session() {
  local sessions
  sessions=(${(f)"$(tmux list-session)"})
+ [[ -n ${tmux_describe} ]] && print "attach or switch to a session" && return
 
- _alternative \
- 'commands:: _describe -t sessions "tmux session" sessions'
+ # If no flag is given, complete with session names.
+ if (( CURRENT == 2 )); then
+ _alternative \
+ 'commands:: _describe -t sessions "tmux session" sessions'
+ return
+ fi
+
+ _arguments -s \
+ '1:sessions' \
+ '-c+[specify working directory for the session]:directory:_directories' \
+ '-d[detach other clients attached to target session]' \
+ '-f+[set client flags]: :_tmux_client_flags' \
+ '-r[put the client into read-only mode]' \
+ '-t+[specify target session]:target session: __tmux-sessions-separately' \
+ "-E[don't apply update-environment option]" \
+ '-x[with -d, send SIGHUP to the parent of the attached client]'
+
+ return
+}
+
+_tmux_client_flags() {
+ _values -s , flag active-pane ignore-size no-output \
+ 'pause-after:time (seconds)' read-only wait-exit
+}
+
+__tmux-sessions-separately() {
+ local ret=1
+ local -a sessions detached_sessions attached_sessions
+ sessions=( ${${(f)"$(command tmux 2> /dev/null list-sessions)"}/:[ $'\t']##/:} )
+ detached_sessions=( ${sessions:#*"(attached)"} )
+ attached_sessions=( ${(M)sessions:#*"(attached)"} )
+
+ # ### This seems to work without a _tags loop but not with it. I suspect
+ # ### that has something to do with _describe doing its own _tags loop.
+ _tags detached-sessions attached-sessions
+ # Placing detached before attached means the default behaviour of this
+ # function better suits its only current caller, _tmux-attach-session().
+ _requested detached-sessions && _describe -t detached-sessions 'detached session' detached_sessions "$@" && ret=0
+ _requested attached-sessions && _describe -t attached-sessions 'attached session' attached_sessions "$@" && ret=0
+
+ return ret
 }
 
 alias tksv='tmux kill-server'
@@ -140,7 +181,7 @@ function _zsh_tmux_plugin_run() {
 compdef _tmux _zsh_tmux_plugin_run
 
 # Provide session name completion for alias functions.
-compdef _session_completion ta tad tkss
+compdef _tmux-attach-session ta tad tkss
 
 # Alias tmux to our wrapper function.
 alias tmux=_zsh_tmux_plugin_run