Re: More-verbose tab-completion idiom?

[Daniel Shahaf <d.s@xxxxxxxxxxxxxxxxxx>]

Phil Pennock wrote on Wed, Mar 16, 2022 at 22:21:44 -0400:
> On 2022-03-16 at 18:20 -0700, Bart Schaefer wrote:
> > but that assumes you don't have colons or commas or braces in the keys
> > or descriptions.
> 
> Alas, one of the fields is almost guaranteed to be a URL, thus
> containing a colon, and all of those are fair game in the description
> field.
> 
> In case anyone is interested: while nats(1) (open-source, part of the
> CNCF "NATS" project) is changing fast enough that we probably don't want
> the completion shipping with zsh at this time, here's a copy of the
> completion I'm using today:
> 
>   https://get-nats.io/zsh.complete.nats

Review in unidiff form.  Meant as suggestions to pick and choose from.

I forgot to annotate a few other function definitions with the same
"don't unconditionaly redefine" idiom.

Cheers,

Daniel


[[[
--- https://get-nats.io/zsh.complete.nats
+++ https://get-nats.io/zsh.complete.nats
@@ -23,7 +23,7 @@
 
 # extra-verbose is documented as for features which will slow completion speed.
 if zstyle -t ":completion:${curcontext}:" extra-verbose; then
-  if (( $+commands[jq] )); then
+  if type jq > /dev/null; then
     nats_everbose=1
   else
     : # should we report this back as an error somehow?
@@ -32,15 +32,16 @@
 
 local -r nats_ctxdir="${XDG_CONFIG_HOME:-$HOME/.config}/nats/context"
 
-nats_contexts=( "$nats_ctxdir"/*(:t:r) )
+nats_contexts=( "$nats_ctxdir"/*(N:t:r) )
 
 # TODO: come up with a cache expiration strategy and integrate this with use-cache
 # or at least a global variable.
+(( ${+functions[_nats_context_names]} )) ||
 _nats_context_names() {
   if (( nats_everbose )); then
     described_contexts=()
     for nctx in "${nats_contexts[@]}"; do
-      described_contexts+=("${nctx//:/\\:}:$(jq -r .description < "$nats_ctxdir/$nctx.json")")
+      described_contexts+=("${nctx//:/\\:}:$(_call_program jq "jq -r .description < \"${(q)nats_ctxdir}/${(q)nctx}.json\"")")
     done
     _describe nats-contexts described_contexts
   else
@@ -55,7 +56,7 @@
     ;;
 esac
 
-nats_decorate_flags_desc=(
+nats_decorate_flags_desc=( # this assumes zsh is-at-least 5.5
 	[context]='NATS user context'
 	[tlscert]='TLS client auth public certificate'
 	[tlskey]='TLS client auth private key'
@@ -86,12 +87,12 @@
 
 # We populate a complete set first, so that even if we don't have more details below,
 # we can still tab-complete it; it will just be missing some data
-nats_commands=( $(${words[1]} --completion-bash ${words[1]}) )
+nats_commands=( $(_call_program completion-bash "${words[1]} --completion-bash ${words[1]}") )
 
 # Most flags can appear anywhere; this is not a git-style "top command flags"
 # vs "subcommand flags", but instead "one pool of flags which gains extra
 # entries for some subcommands".
-nats_flags=( $(${words[1]} --completion-bash ${words[1]} --) )
+nats_flags=( $(${words[1]} --completion-bash ${words[1]} --) ) # TODO add _call_program
 _nats_decorate_flags() {
   #zle -M "decorating ..."; zle -R
   local flag directive
@@ -135,7 +136,7 @@
   ;;
 (after-command)
   curcontext=${curcontext%:*:*}:nats-$words[1]:
-  nats_sub=( $("$cmdword" --completion-bash "${words[@]}") )
+  nats_sub=( $("$cmdword" --completion-bash "${words[@]}") ) # TODO add _call_program
   if [[ ${#nats_sub} -eq 0 ]]; then
     # terminal
     nats_flags=( $("$cmdword" --completion-bash "${words[@]}" --) )
]]]

> (I know that I'm misusing the per-flag description by listing it twice in
> this way for the two different location but I haven't yet come up with
> an easier-to-maintain approach)
> 
> -Phil
>