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

Fixes #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).

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-position1b.zsh

@@ -0,0 +1,36 @@
+#!/usr/bin/env zsh
+# -------------------------------------------------------------------------------------------------
+# Copyright (c) 2020 zsh-syntax-highlighting contributors
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification, are permitted
+# provided that the following conditions are met:
+#
+#  * Redistributions of source code must retain the above copyright notice, this list of conditions
+#    and the following disclaimer.
+#  * Redistributions in binary form must reproduce the above copyright notice, this list of
+#    conditions and the following disclaimer in the documentation and/or other materials provided
+#    with the distribution.
+#  * Neither the name of the zsh-syntax-highlighting contributors nor the names of its contributors
+#    may be used to endorse or promote products derived from this software without specific prior
+#    written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+# FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# -------------------------------------------------------------------------------------------------
+# -*- mode: zsh; sh-indentation: 2; indent-tabs-mode: nil; sh-basic-offset: 2; -*-
+# vim: ft=zsh sw=2 ts=2 et
+# -------------------------------------------------------------------------------------------------
+
+setopt autocd
+BUFFER=$'/'
+
+expected_region_highlight=(
+  '1 1 arg0' # /
+)

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

@@ -31,7 +31,7 @@
 BUFFER=$'/bin; /bin'
 
 expected_region_highlight=(
-  '1 4 path' # /bin (in middle)
+  '1 4 unknown-token' # /bin (in middle)
   '5 5 commandseparator' # ;
-  '7 10 path' # /bin (at end)
+  '7 10 path_prefix' # /bin (at end)
 )

highlighters/main/test-data/abspath-in-command-position3b.zsh

@@ -32,7 +32,7 @@ setopt autocd
 BUFFER=$'/bin; /bin'
 
 expected_region_highlight=(
-  '1 4 path' # /bin (in middle)
+  '1 4 arg0' # /bin (in middle)
   '5 5 commandseparator' # ;
-  '7 10 path' # /bin (at end)
+  '7 10 arg0' # /bin (at end)
 )

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/path-dollared-word3b.zsh

@@ -0,0 +1,39 @@
+#!/usr/bin/env zsh
+# -------------------------------------------------------------------------------------------------
+# Copyright (c) 2020 zsh-syntax-highlighting contributors
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without modification, are permitted
+# provided that the following conditions are met:
+#
+#  * Redistributions of source code must retain the above copyright notice, this list of conditions
+#    and the following disclaimer.
+#  * Redistributions in binary form must reproduce the above copyright notice, this list of
+#    conditions and the following disclaimer in the documentation and/or other materials provided
+#    with the distribution.
+#  * Neither the name of the zsh-syntax-highlighting contributors nor the names of its contributors
+#    may be used to endorse or promote products derived from this software without specific prior
+#    written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+# FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# -------------------------------------------------------------------------------------------------
+# -*- mode: zsh; sh-indentation: 2; indent-tabs-mode: nil; sh-basic-offset: 2; -*-
+# vim: ft=zsh sw=2 ts=2 et
+# -------------------------------------------------------------------------------------------------
+
+setopt autocd
+
+BUFFER=$'$PWD; ${PWD}'
+
+expected_region_highlight=(
+  '1 4 arg0' # $PWD
+  '5 5 commandseparator' # ;
+  '7 12 arg0' # ${PWD}
+)

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

@@ -33,7 +33,7 @@ chmod -x foo
 BUFFER=$'./foo; ./foo'
 
 expected_region_highlight=(
-  '1 5 unknown-token "issue #202"' # ./foo (in middle)
+  '1 5 unknown-token' # ./foo (in middle)
   '6 6 commandseparator' # ;
-  '8 12 unknown-token "issue #202"' # ./foo (at end)
+  '8 12 unknown-token' # ./foo (at end)
 )