Isolate setup code in functions to ease messing with zsh-syntax-highlighting

zsh-syntax-highlighting.zsh

@@ -119,23 +119,20 @@ _zsh_highlight_cursor_moved()
 
 
 # -------------------------------------------------------------------------------------------------
-# Setup
+# Setup functions
 # -------------------------------------------------------------------------------------------------
 
+# Rebind all ZLE widgets to make them invoke _zsh_highlights.
+_zsh_highlight_bind_widgets()
+{
   # Load ZSH module zsh/zleparameter, needed to override user defined widgets.
   zmodload zsh/zleparameter 2>/dev/null || {
-  echo 'zsh-syntax-highlighting: failed loading zsh/zleparameter, exiting.' >&2
+    echo 'zsh-syntax-highlighting: failed loading zsh/zleparameter.' >&2
-  return -1
+    return 1
-}
-
-# Resolve highlighters directory location.
-highlighters_dir="${ZSH_HIGHLIGHT_HIGHLIGHTERS_DIR:-${0:h}/highlighters}"
-[[ -d $highlighters_dir ]] || {
-  echo "zsh-syntax-highlighting: highlighters directory '$highlighters_dir' not found, exiting." >&2
-  return -1
   }
 
   # Override ZLE widgets to make them invoke _zsh_highlight.
+  local cur_widget
   for cur_widget in ${${(f)"$(builtin zle -la)"}:#(.*|orig-*|run-help|which-command|beep)}; do
     case $widgets[$cur_widget] in
 
@@ -160,10 +157,23 @@ for cur_widget in ${${(f)"$(builtin zle -la)"}:#(.*|orig-*|run-help|which-comman
       *) echo "zsh-syntax-highlighting: unhandled ZLE widget '$cur_widget'" >&2 ;;
     esac
   done
-unset cur_widget
+}
+
+# Load highlighters from directory.
+#
+# Arguments:
+#   1) Path to the highlighters directory.
+_zsh_highlight_load_highlighters()
+{
+  # Check the directory exists.
+  [[ -d "$1" ]] || {
+    echo "zsh-syntax-highlighting: highlighters directory '$1' not found." >&2
+    return 1
+  }
 
   # Load highlighters from highlighters directory and check they define required functions.
-for highlighter_dir ($highlighters_dir/*/); do
+  local highlighter highlighter_dir
+  for highlighter_dir ($1/*/); do
     highlighter="${highlighter_dir:t}"
     [[ -f "$highlighter_dir/${highlighter}-highlighter.zsh" ]] && {
       . "$highlighter_dir/${highlighter}-highlighter.zsh"
@@ -173,7 +183,24 @@ for highlighter_dir ($highlighters_dir/*/); do
       }
     }
   done
-unset highlighter highlighter_dir highlighters_dir
+}
+
+
+# -------------------------------------------------------------------------------------------------
+# Setup
+# -------------------------------------------------------------------------------------------------
+
+# Try binding widgets.
+_zsh_highlight_bind_widgets || {
+  echo 'zsh-syntax-highlighting: failed binding ZLE widgets, exiting.' >&2
+  return 1
+}
+
+# Resolve highlighters directory location.
+_zsh_highlight_load_highlighters "${ZSH_HIGHLIGHT_HIGHLIGHTERS_DIR:-${0:h}/highlighters}" || {
+  echo 'zsh-syntax-highlighting: failed loading highlighters, exiting.' >&2
+  return 1
+}
 
 # Initialize the array of active highlighters if needed.
 [[ $#ZSH_HIGHLIGHT_HIGHLIGHTERS -eq 0 ]] && ZSH_HIGHLIGHT_HIGHLIGHTERS=(main)