fix(zsh/completion): ensure brew and brew installed shell completion works

zshenv

@@ -137,19 +137,23 @@ if command-exists brew; then
 
   brew-prefix() {
     local package="$1"
+    local cachekey
 
+    cachekey="$package"
     if [[ -z "$package" ]]; then
-      package="__none__"
+      cachekey="__none__"
     fi
 
-    if [[ -n "${_brew_prefix_cache[$package]}" ]]; then
-      echo "${_brew_prefix_cache[$package]}"
+    if [[ -n "${_brew_prefix_cache[$cachekey]}" ]]; then
+      echo "${_brew_prefix_cache[$cachekey]}"
     else
       local result=$(brew --prefix "$package")
-      _brew_prefix_cache[$package]=$result
-      echo $result
+      _brew_prefix_cache["$cachekey"]="$result"
+      echo "$result"
     fi
   }
+
+  export BREW_SITEFUNS="$(brew-prefix)/share/zsh/site-functions"
 fi
 
 # Linuxbrew

zshrc

@@ -66,6 +66,10 @@ zstyle ':completion:*:make:*' tag-order targets
 
 if [ -d "$ZSH_COMPLETIONS" ]; then fpath=("$ZSH_COMPLETIONS" $fpath); fi
 if [ -d "$DOTZSH_SITEFUNS" ]; then fpath=("$DOTZSH_SITEFUNS" $fpath); fi
+if [ -d "$BREW_SITEFUNS" ]; then fpath=("$BREW_SITEFUNS" $fpath); fi
+
+autoload -Uz compinit
+compinit
 
 # setup-completions is a helper function to setup completions for a given
 # command. It takes the command name, the source of the completion, and the