How do I make the autosuggestions of a zsh function use syntax highlighting - autocomplete

Question

I use zsh and wrote a function to replace cd function. With some help I got it to work like I want it to (mostly). This is a followup to one of my other question.
The function almost works like I want it to, but I still have some problems with syntax highlighting and autocompletion.
For the examples, lets say your directories look like this:
/
a/
b/
c/
d/
some_dir/
I am also assuming the following code has been sourced:
cl () {
local first=$( echo $1 | cut -d/ -f1 )
if [ -d $first ]; then
pushd $1 >/dev/null # If the first argument is an existing normal directory, move there
else
pushd ${PWD%/$first/*}/$1 >/dev/null # Otherwise, move to a parent directory or a child of that parent directory
fi
}
_cl() {
_cd
pth=${words[2]}
opts=""
new=${pth##*/}
local expl
# Generate the visual formatting and store it in `$expl`
_description -V ancestor-directories expl 'ancestor directories'
[[ "$pth" != *"/"*"/"* ]] && middle="" || middle="${${pth%/*}#*/}/"
if [[ "$pth" != *"/"* ]]; then
# If this is the start of the path
# In this case we should also show the parent directories
local ancestor=$PWD:h
while (( $#ancestor > 1 )); do
# -f: Treat this as a file (incl. dirs), so you get proper highlighting.
# -Q: Don't quote (escape) any of the characters.
# -W: Specify the parent of the dir we're adding.
# ${ancestor:h}: The parent ("head") of $ancestor.
# ${ancestor:t}: The short name ("tail") of $ancestor.
compadd "$expl[#]" -fQ -W "${ancestor:h}/" - "${ancestor:t}"
# Move on to the next parent.
ancestor=$ancestor:h
done
else
# $first is the first part of the path the user typed in.
# it it is part of the current direoctory, we know the user is trying to go back to a directory
first=${pth%%/*}
# $middle is the rest of the provided path
if [ ! -d $first ]; then
# path starts with parent directory
dir=${PWD%/$first/*}/$first
first=$first/
# List all sub directories of the $dir/$middle directory
if [ -d "$dir/$middle" ]; then
for d in $(ls -a $dir/$middle); do
if [ -d $dir/$middle/$d ] && [[ "$d" != "." ]] && [[ "$d" != ".." ]]; then
compadd "$expl[#]" -fQ -W $dir/ - $first$middle$d
fi
done
fi
fi
fi
}
compdef _cl cl
The problem:
I use syntax-highlighting, but the path i type is just white (when going to a parent directory. the normal cd functions are colored).
Example:
$ cd /a
$ cl c # 'c' is colored
$ pwd
/a/c
$ cl a/b # 'a/b' is not colored
$ cl a/[tab] # 'a/b', 'a/c' and 'a/some_dir' are not colored
How do I get these paths to be colored?

Answer 1

That's not possible out of the box with the zsh-syntax-highlighting plugin. It checks only whether what you've typed is
A) a valid absolute path or
B) a valid path relative to the present working dir.
This is not specific to your command. Highlighting also fails when specifying path arguments to other commands that are otherwise valid, but are not absolute paths or valid paths relative to the present working dir.
For example:
% cd /a/b
% cd b c # perfectly valid args, but will not get highlighted as valid paths
% pwd
/a/c