'main': In command position, do not highlight directories (unless AUTO_CD is set) and non-executable files. Fixes zsh-users#202.

Test expectations are updated.  For example, BUFFER='/bin' is now
highlighted as path_prefix because it's a prefix of '/bin/sh' which
would be valid.  However, BUFFER='/bin;' is now properly highlighted
as an error (unless AUTO_CD is set).

Author: danielshahaf

highlighters/main/main-highlighter.zsh

@@ -857,7 +857,7 @@ _zsh_highlight_main_highlighter_highlight_list()
                           fi
                           _zsh_highlight_main__stack_pop 'R' reserved-word
                         else
-                          if _zsh_highlight_main_highlighter_check_path $arg; then
+                          if _zsh_highlight_main_highlighter_check_path $arg 1; then
                             style=$REPLY
                           else
                             style=unknown-token
@@ -960,10 +960,13 @@ _zsh_highlight_main_highlighter_highlight_path_separators()
 # Check if $1 is a path.
 # If yes, return 0 and in $REPLY the style to use.
 # Else, return non-zero (and the contents of $REPLY is undefined).
+#
+# $2 should be non-zero iff we're in command position.
 _zsh_highlight_main_highlighter_check_path()
 {
   _zsh_highlight_main_highlighter_expand_path "$1"
   local expanded_path="$REPLY" tmp_path
+  integer in_command_position=$2
 
   REPLY=path
 
@@ -982,16 +985,25 @@ _zsh_highlight_main_highlighter_check_path()
     tmp_path=$tmp_path:h
   done
 
-  [[ -L $expanded_path ]] && return 0
-  [[ -e $expanded_path ]] && return 0
+  if (( in_command_position )); then
+    if [[ -x $expanded_path ]] && [[ $zsyh_user_options[autocd] == on || ! -d $expanded_path ]]; then
+      return 0
+    fi
+  else
+    if [[ -L $expanded_path || -e $expanded_path ]]; then
+      return 0
+    fi
+  fi
 
   # Search the path in CDPATH
   if [[ $expanded_path != /* ]]; then
-    local cdpath_dir
     # TODO: When we've dropped support for pre-5.0.6 zsh, use the *(Y1) glob qualifier here.
-    for cdpath_dir in $cdpath ; do
-      [[ -e "$cdpath_dir/$expanded_path" ]] && return 0
-    done
+    if (( ! in_command_position )) || [[ $zsyh_user_options[autocd] == on ]]; then
+      local cdpath_dir
+      for cdpath_dir in $cdpath ; do
+        [[ -d "$cdpath_dir/$expanded_path" && -x "$cdpath_dir/$expanded_path" ]] && return 0
+      done
+    fi
   fi
 
   # If dirname($1) doesn't exist, neither does $1.
@@ -1012,6 +1024,8 @@ _zsh_highlight_main_highlighter_check_path()
 # Highlight an argument and possibly special chars in quotes starting at $1 in $arg
 # This command will at least highlight $1 to end_pos with the default style
 # If $2 is set to 0, the argument cannot be highlighted as an option.
+#
+# This function currently assumes it's never called for the command word.
 _zsh_highlight_main_highlighter_highlight_argument()
 {
   local base_style=default i=$1 option_eligible=${2:-1} path_eligible=1 ret start style
@@ -1132,7 +1146,8 @@ _zsh_highlight_main_highlighter_highlight_argument()
     esac
   done
 
-  if (( path_eligible )) && _zsh_highlight_main_highlighter_check_path $arg[$1,-1]; then
+  # This function is currently never called for the command word, so $2 is hard-coded as 0.
+  if (( path_eligible )) && _zsh_highlight_main_highlighter_check_path $arg[$1,-1] 0; then
     base_style=$REPLY
     _zsh_highlight_main_highlighter_highlight_path_separators $base_style
     highlights+=($reply)

highlighters/main/test-data/abspath-in-command-position1.zsh

@@ -31,5 +31,5 @@
 BUFFER=$'/'
 
 expected_region_highlight=(
-  '1 1 path' # /
+  '1 1 path_prefix' # /
 )

highlighters/main/test-data/abspath-in-command-position3.zsh

@@ -28,6 +28,7 @@
 # vim: ft=zsh sw=2 ts=2 et
 # -------------------------------------------------------------------------------------------------
 
+setopt autocd
 BUFFER=$'/bin'
 
 expected_region_highlight=(

highlighters/main/test-data/path-dollared-word3.zsh

@@ -34,7 +34,7 @@
 BUFFER='$PWD; ${PWD}'
 
 expected_region_highlight=(
-  "1 4 path" # $PWD
+  "1 4 unknown-token" # $PWD (without AUTO_CD)
   "5 5 commandseparator" # ;
-  "7 12 path" # ${PWD}
+  "7 12 path_prefix" # ${PWD}
 )

highlighters/main/test-data/plain-file-in-command-position.zsh

@@ -33,7 +33,7 @@ chmod -x foo
 BUFFER=$'./foo bar'
 
 expected_region_highlight=(
-  '1 5 unknown-token "issue #202"' # ./foo
+  '1 5 unknown-token' # ./foo
   # The only reason 'bar' is here because at this time BUFFER='./foo' is (not
   # quite correctly) highlighted as 'path_prefix'.  The test will remain
   # forever valid, even if that 'path_prefix' issue is fixed, though.