Re: Feature Patch: Use completion to view parameter values

[Marlon Richert <marlon.richert@xxxxxxxxx>]

On Mon, Mar 29, 2021 at 10:39 AM Daniel Shahaf <d.s@xxxxxxxxxxxxxxxxxx> wrote:
> What about parameters implemented by modules?  The getters of those may
> run arbitrary code, and may have side effects: e.g., imagine an
> $AUTOINCREMENT parameter that returns an incremented-by-one value every
> time it's evaluated:

Is there a way to identify these somehow, so I could filter them out?
How about if I never auto-evaluate "special" parameters? So, like
this:

diff --git a/Completion/Zsh/Type/_parameters b/Completion/Zsh/Type/_parameters
index 207e5cf78..4cc8171b0 100644
--- a/Completion/Zsh/Type/_parameters
+++ b/Completion/Zsh/Type/_parameters
@@ -6,13 +6,18 @@
 # If you specify a -g option with a pattern, the pattern will be used to
 # restrict the type of parameters matched.

-local expl pattern fakes faked tmp i pfilt
+local MATCH MBEGIN MEND \
+  disp dopt expl fakes faked i matches pattern pfilt sep tmp

 if compset -P '*:'; then
   _history_modifiers p
   return
 fi

+_tags parameters
+( _tags && _requested parameters ) ||
+  return
+
 pattern=(-g \*)
 zparseopts -D -K -E g:=pattern

@@ -32,8 +37,19 @@ zstyle -t ":completion:${curcontext}:parameters"
prefix-needed && \
  [[ $PREFIX != [_.]* ]] && \
  pfilt='[^_.]'

-_wanted parameters expl parameter \
-    compadd "$@" -Q - \
-        "${(@M)${(@k)parameters[(R)${pattern[2]}~*local*]}:#${~pfilt}*}" \
-        "$fakes[@]" \
-        "${(@)${(@M)faked:#${~pattern[2]}}%%:*}"
+_description parameters expl parameter
+compadd "$expl[@]" -O matches - \
+  "${(@M)${(@k)parameters[(R)${pattern[2]}~*local*]}:#${~pfilt}*}" \
+  "$fakes[@]" \
+  "${(@)${(@M)faked:#${~pattern[2]}}%%:*}"
+
+if zstyle -t ":completion:${curcontext}:parameters" extra-verbose; then
+  zstyle -s ":completion:${curcontext}:parameters" list-separator sep ||
+    sep=--
+  zformat -a disp " $sep " \
+    ${matches[@]:/(#m)*/"${MATCH}:${${(t)${(P)MATCH}:#*special*}:+${(Pkv@q+)MATCH}}"}
+  disp=( "${disp[@]:/(#m)*/$MATCH[1,COLUMNS]}" )
+  dopt=( -d disp )
+fi
+
+compadd "$expl[@]" $dopt -Q -a matches
diff --git a/Test/Y01completion.ztst b/Test/Y01completion.ztst
index 571f3cf16..e5901b8e5 100644
--- a/Test/Y01completion.ztst
+++ b/Test/Y01completion.ztst
@@ -222,7 +222,7 @@ F:regression test workers/31611
   comptesteval "zstyle ':completion:*:tst:*' ignored-patterns 2"
   comptest $'tst 1,\t'
   comptesteval "zstyle -d ':completion:*:tst:*' ignored-patterns"
-0:-F doesn't break _sequence
+0:-F doesn’t break _sequence
 >line: {tst 1,}{}
 >DESCRIPTION:{desc}
 >NO:{2}
@@ -237,6 +237,28 @@ F:regression test workers/31611
 >FI:{file1}
 >FI:{file2}

+  comptesteval "bar=({$'\\0'..$'\\C-?'}); baz=\$bar"
+  comptesteval 'zstyle ":completion:*:parameters" extra-verbose yes'
+  comptest $': $ba\t'
+0:extra-verbose shows parameter values
+>line: {: $ba}{}
+>DESCRIPTION:{parameter}
+>NO:{bar -- '^@' '^A' '^B' '^C' '^D' '^E' '^F' '^G' '^H' '\t' '\n'
'^K' '^L' '^M' '^N}
+>NO:{baz -- '^@ ^A ^B ^C ^D ^E ^F ^G ^H \t \n ^K ^L ^M ^N ^O ^P ^Q ^R
^S ^T ^U ^V ^W }
+
+  comptest $': $path\C-D'
+0:extra-verbose does not show special parameter values
+>DESCRIPTION:{parameter}
+>NO:{path}
+
+  comptesteval 'zstyle -d ":completion:*:parameters" extra-verbose'
+  comptest $': $ba\t'
+0:parameter values not shown without extra-verbose
+>line: {: $ba}{}
+>DESCRIPTION:{parameter}
+>NO:{bar}
+>NO:{baz}
+
   comptesteval '_tst() { local disp=( {a..z} ); compadd -ld disp
$disp[@]; comppostfuncs=( _pst ) }'
   comptesteval '_pst() { local disp=(
"<INSERT>$compstate[insert]</INSERT>" ); compadd -Qld disp $disp }'
   comptesteval "zstyle ':completion:*' menu select=long-list"