fixes for zle handling

README.md

@@ -32,6 +32,15 @@ custom widgets have been created (i.e., after all `zle -N` calls and after
 running `compinit`).  Widgets created later will work, but will not update the
 syntax highlighting.
 
+### Why does syntax highlighting not work while searching history?
+
+In `zsh` versions before 5.3 is not possible for `zsh-syntax-highlighting.zsh`
+to know if an incremental search is currently active and that matched parts of the
+buffer should be underlined (or otherwise highlighted). Therefore, it is not possible
+for `zsh-syntax-highlighting.zsh` to apply syntax highlighting and to underline the
+matched part of the search. While searching the history, the latter is more important,
+so syntax highlighting is disabled in this case.
+
 ### How are new releases announced?
 
 There is currently no "push" announcements channel.  However, the following

highlighters/cursor/cursor-highlighter.zsh

@@ -34,15 +34,14 @@
 # Whether the cursor highlighter should be called or not.
 _zsh_highlight_cursor_highlighter_predicate()
 {
-  # accept-* may trigger removal of cursor highlighting
-  [[ $WIDGET == accept-* ]] ||
-    _zsh_highlight_cursor_moved
+  # remove cursor highlighting when the line is finished
+  [[ $WIDGET == zle-line-finish ]] || _zsh_highlight_cursor_moved
 }
 
 # Cursor highlighting function.
 _zsh_highlight_cursor_highlighter()
 {
-  [[ $WIDGET == accept-* ]] && return
+  [[ $WIDGET == zle-line-finish ]] && return
 
   _zsh_highlight_add_highlight $CURSOR $(( $CURSOR + 1 )) cursor
 }

highlighters/main/main-highlighter.zsh

@@ -62,9 +62,8 @@
 # Whether the highlighter should be called or not.
 _zsh_highlight_main_highlighter_predicate()
 {
-  # accept-* may trigger removal of path_prefix highlighting
-  [[ $WIDGET == accept-* ]] ||
-    _zsh_highlight_buffer_modified
+  # may need to remove path_prefix highlighting when the line ends
+  [[ $WIDGET == zle-line-finish ]] || _zsh_highlight_buffer_modified
 }
 
 # Helper to deal with tokens crossing line boundaries.
@@ -595,7 +594,7 @@ _zsh_highlight_main_highlighter_check_path()
 
   # If this word ends the buffer, check if it's the prefix of a valid path.
   if [[ ${BUFFER[1]} != "-" && ${#BUFFER} == $end_pos ]] &&
-     [[ $WIDGET != accept-* ]]; then
+     [[ $WIDGET != zle-line-finish ]]; then
     local -a tmp
     tmp=( ${expanded_path}*(N) )
     (( $#tmp > 0 )) && REPLY=path_prefix && return 0

highlighters/main/test-data/path_prefix2.zsh

@@ -31,7 +31,7 @@
 # Related to path_prefix.zsh
 
 BUFFER='ls /bin/s'
-WIDGET=accept-line
+WIDGET=zle-line-finish
 
 expected_region_highlight=(
   "4 9 default"    # /bin/s

zsh-syntax-highlighting.zsh

@@ -58,6 +58,14 @@ _zsh_highlight()
   # Store the previous command return code to restore it whatever happens.
   local ret=$?
 
+  # Remove all highlighting in isearch, so that only the underlining done by zsh itself remains.
+  # For details see FAQ entry 'Why does syntax highlighting not work while searching history?'
+  # and http://www.zsh.org/mla/users/2016/msg00415.html.
+  if [[ $WIDGET == zle-isearch-update ]]; then
+    region_highlight=()
+    return $ret
+  fi
+
   setopt localoptions warncreateglobal
   setopt localoptions noksharrays
   local REPLY # don't leak $REPLY into global scope
@@ -235,8 +243,20 @@ _zsh_highlight_bind_widgets()
   }
 
   # Override ZLE widgets to make them invoke _zsh_highlight.
+  local -U widgets_to_bind
+  widgets_to_bind=(${${(k)widgets}:#(.*|orig-*|run-help|which-command|beep|set-local-history|yank)})
+
+  # Always wrap special zle-line-finish widget. This is needed to decide if the
+  # current line ends and special highlighting logic needs to be applied.
+  # E.g. remove cursor imprint, don't highlight partial paths, ...
+  widgets_to_bind+=(zle-line-finish)
+
+  # Always wrap special zle-isearch-update widget to be notified of updates in isearch.
+  # This is needed because we need to disable highlighting in that case.
+  widgets_to_bind+=(zle-isearch-update)
+
   local cur_widget
-  for cur_widget in ${${(k)widgets}:#(.*|orig-*|run-help|which-command|beep|set-local-history|yank)}; do
+  for cur_widget in $widgets_to_bind; do
     case $widgets[$cur_widget] in
 
       # Already rebound event: do nothing.
@@ -262,6 +282,10 @@ _zsh_highlight_bind_widgets()
       builtin) eval "_zsh_highlight_widget_${(q)cur_widget}() { _zsh_highlight_call_widget .${(q)cur_widget} -- \"\$@\" }"
                zle -N $cur_widget _zsh_highlight_widget_$cur_widget;;
 
+      # Special zle-* hook that is currently not bound at all: Bind to z-sy-h driectly.
+      '') eval "_zsh_highlight_widget_${(q)cur_widget}() { :; _zsh_highlight }"
+          zle -N $cur_widget _zsh_highlight_widget_$cur_widget;;
+
       # Default: unhandled case.
       *) echo "zsh-syntax-highlighting: unhandled ZLE widget '$cur_widget'" >&2 ;;
     esac