From 585696eeeb4e838e65bd43263ac7388558765024 Mon Sep 17 00:00:00 2001
From: Roman Perepelitsa <roman.perepelitsa@gmail.com>
Date: Sun, 19 Jul 2020 11:03:10 +0200
Subject: [PATCH] bug fix: infinite loop when cwd doesn't exist

To reproduce:

    % mkdir /tmp/foo
    % cd /tmp/foo
    % rmdir /tmp/foo
    % exec zsh -f
    % source ~/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh

Press 'a' and zle will hang.
---
 highlighters/main/main-highlighter.zsh | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/highlighters/main/main-highlighter.zsh b/highlighters/main/main-highlighter.zsh
index e59c61c..e229927 100644
--- a/highlighters/main/main-highlighter.zsh
+++ b/highlighters/main/main-highlighter.zsh
@@ -1211,14 +1211,18 @@ _zsh_highlight_main_highlighter_check_path()
   if [[ $expanded_path[1] == / ]]; then
     tmp_path=$expanded_path
   else
-    tmp_path=$PWD/$expanded_path
+    # Unlike $PWD, ${(%):-%/} predictably expands to '.' if the current
+    # working directory doesn't exist.
+    tmp_path=${(%):-%/}/$expanded_path
   fi
   tmp_path=$tmp_path:a
 
-  while [[ $tmp_path != / ]]; do
-    [[ -n ${(M)ZSH_HIGHLIGHT_DIRS_BLACKLIST:#$tmp_path} ]] && return 1
-    tmp_path=$tmp_path:h
-  done
+  if [[ $tmp_path == /* ]]; then
+    while [[ $tmp_path != / ]]; do
+      [[ -n ${(M)ZSH_HIGHLIGHT_DIRS_BLACKLIST:#$tmp_path} ]] && return 1
+      tmp_path=$tmp_path:h
+    done
+  fi
 
   if (( in_command_position )); then
     if [[ -x $expanded_path ]]; then