zsh-syntax-highlighting/highlighters/main/main-highlighter.zsh

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# -------------------------------------------------------------------------------------------------
# Copyright (c) 2010-2015 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
# -------------------------------------------------------------------------------------------------
# Define default styles.
: ${ZSH_HIGHLIGHT_STYLES[default]:=none}
: ${ZSH_HIGHLIGHT_STYLES[unknown-token]:=fg=red,bold}
: ${ZSH_HIGHLIGHT_STYLES[reserved-word]:=fg=yellow}
: ${ZSH_HIGHLIGHT_STYLES[alias]:=fg=green}
: ${ZSH_HIGHLIGHT_STYLES[suffix-alias]:=fg=green,underline}
: ${ZSH_HIGHLIGHT_STYLES[builtin]:=fg=green}
: ${ZSH_HIGHLIGHT_STYLES[function]:=fg=green}
: ${ZSH_HIGHLIGHT_STYLES[command]:=fg=green}
: ${ZSH_HIGHLIGHT_STYLES[precommand]:=fg=green,underline}
: ${ZSH_HIGHLIGHT_STYLES[commandseparator]:=none}
: ${ZSH_HIGHLIGHT_STYLES[hashed-command]:=fg=green}
: ${ZSH_HIGHLIGHT_STYLES[path]:=underline}
: ${ZSH_HIGHLIGHT_STYLES[path_prefix]:=underline}
: ${ZSH_HIGHLIGHT_STYLES[globbing]:=fg=blue}
: ${ZSH_HIGHLIGHT_STYLES[history-expansion]:=fg=blue}
: ${ZSH_HIGHLIGHT_STYLES[single-hyphen-option]:=none}
: ${ZSH_HIGHLIGHT_STYLES[double-hyphen-option]:=none}
: ${ZSH_HIGHLIGHT_STYLES[back-quoted-argument]:=none}
: ${ZSH_HIGHLIGHT_STYLES[single-quoted-argument]:=fg=yellow}
: ${ZSH_HIGHLIGHT_STYLES[double-quoted-argument]:=fg=yellow}
: ${ZSH_HIGHLIGHT_STYLES[dollar-quoted-argument]:=fg=yellow}
: ${ZSH_HIGHLIGHT_STYLES[dollar-double-quoted-argument]:=fg=cyan}
: ${ZSH_HIGHLIGHT_STYLES[back-double-quoted-argument]:=fg=cyan}
: ${ZSH_HIGHLIGHT_STYLES[back-dollar-quoted-argument]:=fg=cyan}
: ${ZSH_HIGHLIGHT_STYLES[assign]:=none}
: ${ZSH_HIGHLIGHT_STYLES[redirection]:=none}
: ${ZSH_HIGHLIGHT_STYLES[comment]:=fg=black,bold}
# 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
}
# Helper to deal with tokens crossing line boundaries.
_zsh_highlight_main_add_region_highlight() {
integer start=$1 end=$2
local style=$3
# The calculation was relative to $PREBUFFER$BUFFER, but region_highlight is
# relative to $BUFFER.
(( start -= $#PREBUFFER ))
(( end -= $#PREBUFFER ))
(( end < 0 )) && return # having end<0 would be a bug
(( start < 0 )) && start=0 # having start<0 is normal with e.g. multiline strings
region_highlight+=("$start $end $style")
}
# Wrapper around 'type -w'.
#
# Takes a single argument and outputs the output of 'type -w $1'.
#
# NOTE: This runs 'setopt', but that should be safe since it'll only ever be
# called inside a $(...) subshell, so the effects will be local.
_zsh_highlight_main__type() {
if (( $#options_to_set )); then
setopt $options_to_set;
fi
LC_ALL=C builtin type -w -- $1 2>/dev/null
}
# Main syntax highlighting function.
_zsh_highlight_main_highlighter()
{
## Before we even 'emulate -L', we must test a few options that would reset.
if [[ -o interactive_comments ]]; then
local interactive_comments= # set to empty
fi
if [[ -o path_dirs ]]; then
integer path_dirs_was_set=1
else
integer path_dirs_was_set=0
fi
emulate -L zsh
setopt localoptions extendedglob bareglobqual
## Variable declarations and initializations
local start_pos=0 end_pos highlight_glob=true arg style
local in_array_assignment=false # true between 'a=(' and the matching ')'
typeset -a ZSH_HIGHLIGHT_TOKENS_COMMANDSEPARATOR
typeset -a ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS
typeset -a ZSH_HIGHLIGHT_TOKENS_CONTROL_FLOW
local -a options_to_set # used in callees
local buf="$PREBUFFER$BUFFER"
region_highlight=()
if (( path_dirs_was_set )); then
options_to_set+=( PATH_DIRS )
fi
unset path_dirs_was_set
ZSH_HIGHLIGHT_TOKENS_COMMANDSEPARATOR=(
'|' '||' ';' '&' '&&'
)
ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS=(
'builtin' 'command' 'exec' 'nocorrect' 'noglob'
)
# Tokens that, at (naively-determined) "command position", are followed by
# a de jure command position. All of these are reserved words.
ZSH_HIGHLIGHT_TOKENS_CONTROL_FLOW=(
$'\x7b' # block
$'\x28' # subshell
'()' # anonymous function
'while'
'until'
'if'
'then'
'elif'
'else'
'do'
'time'
'coproc'
'!' # reserved word; unrelated to $histchars[1]
)
# State machine
#
# The states are:
# - :start: Command word
# - :sudo_opt: A leading-dash option to sudo (such as "-u" or "-i")
# - :sudo_arg: The argument to a sudo leading-dash option that takes one,
# when given as a separate word; i.e., "foo" in "-u foo" (two
# words) but not in "-ufoo" (one word).
# - :regular: "Not a command word".
# Mainly used to detect premature termination of commands.
#
# When the kind of a word is not yet known, $this_word / $next_word may contain
# multiple states. For example, after "sudo -i", the next word may be either
# another --flag or a command name, hence the state would include both :start:
# and :sudo_opt:.
#
# The tokens are always added with both leading and trailing colons to serve as
# word delimiters (an improvised array); [[ $x == *:foo:* ]] and x=${x//:foo:/}
# will DTRT regardless of how many elements or repetitions $x has..
#
# Handling of redirections: upon seeing a redirection token, we must stall
# the current state --- that is, the value of $this_word --- for two iterations
# (one for the redirection operator, one for the word following it representing
# the redirection target). Therefore, we set $in_redirection to 2 upon seeing a
# redirection operator, decrement it each iteration, and stall the current state
# when it is non-zero. Thus, upon reaching the next word (the one that follows
# the redirection operator and target), $this_word will still contain values
# appropriate for the word immediately following the word that preceded the
# redirection operator.
#
# The "the previous word was a redirection operator" state is not communicated
# to the next iteration via $next_word/$this_word as usual, but via
# $in_redirection. The value of $next_word from the iteration that processed
# the operator is discarded.
#
local this_word=':start:' next_word
integer in_redirection
for arg in ${interactive_comments-${(z)buf}} \
${interactive_comments+${(zZ+c+)buf}}; do
if (( in_redirection )); then
(( --in_redirection ))
fi
if (( in_redirection == 0 )); then
next_word=':regular:'
fi
# $already_added is set to 1 to disable adding an entry to region_highlight
# for this iteration. Currently, that is done for "" and $'' strings,
# which add the entry early so escape sequences within the string override
# the string's color.
integer already_added=0
local style_override=""
if [[ $this_word == *':start:'* ]]; then
in_array_assignment=false
if [[ $arg == 'noglob' ]]; then
highlight_glob=false
fi
fi
# advance $start_pos, skipping over whitespace in $buf.
if [[ $arg == ';' ]] ; then
# We're looking for either a semicolon or a newline, whichever comes
# first. Both of these are rendered as a ";" (SEPER) by the ${(z)..}
# flag.
#
# We can't use the (Z+n+) flag because that elides the end-of-command
# token altogether, so 'echo foo\necho bar' (two commands) becomes
# indistinguishable from 'echo foo echo bar' (one command with three
# words for arguments).
local needle=$'[;\n]'
integer offset=${${buf[start_pos+1,-1]}[(i)$needle]}
(( start_pos += offset - 1 ))
(( end_pos = start_pos + $#arg ))
else
((start_pos+=${#buf[$start_pos+1,-1]}-${#${buf[$start_pos+1,-1]##([[:space:]]|\\[[:space:]])#}}))
((end_pos=$start_pos+${#arg}))
fi
if [[ -n ${interactive_comments+'set'} && $arg[1] == $histchars[3] ]]; then
if [[ $this_word == *(':regular:'|':start:')* ]]; then
style=$ZSH_HIGHLIGHT_STYLES[comment]
else
style=$ZSH_HIGHLIGHT_STYLES[unknown-token] # prematurely terminated
fi
_zsh_highlight_main_add_region_highlight $start_pos $end_pos $style
already_added=1
continue
fi
# Parse the sudo command line
if (( ! in_redirection )); then
if [[ $this_word == *':sudo_opt:'* ]]; then
case "$arg" in
# Flag that requires an argument
'-'[Cgprtu]) this_word=${this_word//:start:/};
next_word=':sudo_arg:';;
# This prevents misbehavior with sudo -u -otherargument
'-'*) this_word=${this_word//:start:/};
next_word+=':start:';
next_word+=':sudo_opt:';;
*) ;;
esac
elif [[ $this_word == *':sudo_arg:'* ]]; then
next_word+=':sudo_opt:'
next_word+=':start:'
fi
fi
if [[ $this_word == *':start:'* ]] && (( in_redirection == 0 )); then # $arg is the command word
if [[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS:#"$arg"} ]]; then
style=$ZSH_HIGHLIGHT_STYLES[precommand]
elif [[ "$arg" = "sudo" ]]; then
style=$ZSH_HIGHLIGHT_STYLES[precommand]
next_word=${next_word//:regular:/}
next_word+=':sudo_opt:'
next_word+=':start:'
else
_zsh_highlight_main_highlighter_expand_path $arg
local expanded_arg="$REPLY"
local res="$(_zsh_highlight_main__type ${expanded_arg})"
() {
# Special-case: command word is '$foo', like that, without braces or anything.
#
# That's not entirely correct --- if the parameter's value happens to be a reserved
# word, the parameter expansion will be highlighted as a reserved word --- but that
# incorrectness is outweighed by the usability improvement of permitting the use of
# parameters that refer to commands, functions, and builtins.
local -a match mbegin mend
local MATCH; integer MBEGIN MEND
if [[ $res == *': none' ]] && (( ${+parameters} )) &&
[[ ${arg[1]} == \$ ]] && [[ ${arg:1} =~ ^([A-Za-z_][A-Za-z0-9_]*|[0-9]+)$ ]]; then
res="$(_zsh_highlight_main__type ${(P)MATCH})"
fi
}
case $res in
*': reserved') style=$ZSH_HIGHLIGHT_STYLES[reserved-word];;
*': suffix alias')
style=$ZSH_HIGHLIGHT_STYLES[suffix-alias]
;;
*': alias') style=$ZSH_HIGHLIGHT_STYLES[alias]
local aliased_command="${"$(alias -- $arg)"#*=}"
[[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS:#"$aliased_command"} && -z ${(M)ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS:#"$arg"} ]] && ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS+=($arg)
;;
*': builtin') style=$ZSH_HIGHLIGHT_STYLES[builtin];;
*': function') style=$ZSH_HIGHLIGHT_STYLES[function];;
*': command') style=$ZSH_HIGHLIGHT_STYLES[command];;
*': hashed') style=$ZSH_HIGHLIGHT_STYLES[hashed-command];;
*) if _zsh_highlight_main_highlighter_check_assign; then
style=$ZSH_HIGHLIGHT_STYLES[assign]
if [[ $arg[-1] == '(' ]]; then
in_array_assignment=true
else
# assignment to a scalar parameter.
# (For array assignments, the command doesn't start until the ")" token.)
next_word+=':start:'
fi
elif [[ $arg[0,1] == $histchars[0,1] || $arg[0,1] == $histchars[2,2] ]]; then
style=$ZSH_HIGHLIGHT_STYLES[history-expansion]
elif [[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_COMMANDSEPARATOR:#"$arg"} ]] &&
[[ $this_word == *':regular:'* ]]; then
# This highlights empty commands (semicolon follows nothing) as an error.
# Zsh accepts them, though.
style=$ZSH_HIGHLIGHT_STYLES[commandseparator]
elif [[ $arg[1] == '<' || $arg[1] == '>' ]]; then
style=$ZSH_HIGHLIGHT_STYLES[redirection]
(( in_redirection=2 ))
elif [[ $arg[1,2] == '((' ]]; then
# Arithmetic evaluation.
#
# Note: prior to zsh-5.1.1-52-g4bed2cf (workers/36669), the ${(z)...}
# splitter would only output the '((' token if the matching '))' had
# been typed. Therefore, under those versions of zsh, BUFFER="(( 42"
# would be highlighted as an error until the matching "))" are typed.
#
# We highlight just the opening parentheses, as a reserved word; this
# is how [[ ... ]] is highlighted, too.
style=$ZSH_HIGHLIGHT_STYLES[reserved-word]
_zsh_highlight_main_add_region_highlight $start_pos $((start_pos + 2)) $style
already_added=1
if [[ $arg[-2,-1] == '))' ]]; then
_zsh_highlight_main_add_region_highlight $((end_pos - 2)) $end_pos $style
already_added=1
fi
elif [[ $arg == '()' || $arg == $'\x28' ]]; then
# anonymous function
# subshell
style=$ZSH_HIGHLIGHT_STYLES[reserved-word]
else
if _zsh_highlight_main_highlighter_check_path; then
style=$ZSH_HIGHLIGHT_STYLES[path]
else
style=$ZSH_HIGHLIGHT_STYLES[unknown-token]
fi
fi
;;
esac
fi
else # $arg is a non-command word
case $arg in
$'\x29') # subshell or end of array assignment
if $in_array_assignment; then
style=$ZSH_HIGHLIGHT_STYLES[assign]
in_array_assignment=false
else
style=$ZSH_HIGHLIGHT_STYLES[reserved-word]
fi;;
$'\x7d') style=$ZSH_HIGHLIGHT_STYLES[reserved-word];; # block
'--'*) style=$ZSH_HIGHLIGHT_STYLES[double-hyphen-option];;
'-'*) style=$ZSH_HIGHLIGHT_STYLES[single-hyphen-option];;
"'"*) style=$ZSH_HIGHLIGHT_STYLES[single-quoted-argument];;
'"'*) style=$ZSH_HIGHLIGHT_STYLES[double-quoted-argument]
_zsh_highlight_main_add_region_highlight $start_pos $end_pos $style
_zsh_highlight_main_highlighter_highlight_string
already_added=1
;;
\$\'*) style=$ZSH_HIGHLIGHT_STYLES[dollar-quoted-argument]
_zsh_highlight_main_add_region_highlight $start_pos $end_pos $style
_zsh_highlight_main_highlighter_highlight_dollar_string
already_added=1
;;
'`'*) style=$ZSH_HIGHLIGHT_STYLES[back-quoted-argument];;
[*?]*|*[^\\][*?]*)
$highlight_glob && style=$ZSH_HIGHLIGHT_STYLES[globbing] || style=$ZSH_HIGHLIGHT_STYLES[default];;
*) if false; then
elif [[ $arg[0,1] = $histchars[0,1] ]]; then
style=$ZSH_HIGHLIGHT_STYLES[history-expansion]
elif [[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_COMMANDSEPARATOR:#"$arg"} ]]; then
if [[ $this_word == *':regular:'* ]]; then
style=$ZSH_HIGHLIGHT_STYLES[commandseparator]
else
style=$ZSH_HIGHLIGHT_STYLES[unknown-token]
fi
elif [[ $arg[1] == '<' || $arg[1] == '>' ]]; then
style=$ZSH_HIGHLIGHT_STYLES[redirection]
(( in_redirection=2 ))
else
if _zsh_highlight_main_highlighter_check_path; then
style=$ZSH_HIGHLIGHT_STYLES[path]
else
style=$ZSH_HIGHLIGHT_STYLES[default]
fi
fi
;;
esac
fi
# if a style_override was set (eg in _zsh_highlight_main_highlighter_check_path), use it
[[ -n $style_override ]] && style=$ZSH_HIGHLIGHT_STYLES[$style_override]
(( already_added )) || _zsh_highlight_main_add_region_highlight $start_pos $end_pos $style
if [[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_COMMANDSEPARATOR:#"$arg"} ]]; then
next_word=':start:'
elif
[[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_CONTROL_FLOW:#"$arg"} && $this_word == *':start:' ]] ||
[[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_PRECOMMANDS:#"$arg"} && $this_word == *':start:' ]]; then
next_word=':start:'
elif [[ $arg == "repeat" && $this_word == *':start:'* ]]; then
# skip the repeat-count word
in_redirection=2
# The redirection mechanism assumes $this_word describes the word
# following the redirection. Make it so.
#
# The repeat-count word will be handled like a redirection target.
this_word=':start:'
fi
[[ -n ${(M)ZSH_HIGHLIGHT_TOKENS_COMMANDSEPARATOR:#"$arg"} ]] && highlight_glob=true
start_pos=$end_pos
(( in_redirection == 0 )) && this_word=$next_word
done
}
# Check if $arg is variable assignment
_zsh_highlight_main_highlighter_check_assign()
{
setopt localoptions extended_glob
[[ $arg == [[:alpha:]_][[:alnum:]_]#(|\[*\])(|[+])=* ]]
}
# Check if $arg is a path.
_zsh_highlight_main_highlighter_check_path()
{
_zsh_highlight_main_highlighter_expand_path $arg;
local expanded_path="$REPLY"
[[ -z $expanded_path ]] && return 1
[[ -e $expanded_path ]] && return 0
# Search the path in CDPATH
local cdpath_dir
for cdpath_dir in $cdpath ; do
[[ -e "$cdpath_dir/$expanded_path" ]] && return 0
done
# If dirname($arg) doesn't exist, neither does $arg.
[[ ! -e ${expanded_path:h} ]] && return 1
# 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
local -a tmp
tmp=( ${expanded_path}*(N) )
(( $#tmp > 0 )) && style_override=path_prefix && return 0
fi
# It's not a path.
return 1
}
# Highlight special chars inside double-quoted strings
_zsh_highlight_main_highlighter_highlight_string()
{
setopt localoptions noksharrays
local -a match mbegin mend
local MATCH; integer MBEGIN MEND
local i j k style
# Starting quote is at 1, so start parsing at offset 2 in the string.
for (( i = 2 ; i < end_pos - start_pos ; i += 1 )) ; do
(( j = i + start_pos - 1 ))
(( k = j + 1 ))
case "$arg[$i]" in
'$' ) style=$ZSH_HIGHLIGHT_STYLES[dollar-double-quoted-argument]
# Look for an alphanumeric parameter name.
if [[ ${arg:$i} =~ ^([A-Za-z_][A-Za-z0-9_]*|[0-9]+) ]] ; then
(( k += $#MATCH )) # highlight the parameter name
(( i += $#MATCH )) # skip past it
elif [[ ${arg:$i} =~ ^[{]([A-Za-z_][A-Za-z0-9_]*|[0-9]+)[}] ]] ; then
(( k += $#MATCH )) # highlight the parameter name and braces
(( i += $#MATCH )) # skip past it
else
continue
fi
;;
"\\") style=$ZSH_HIGHLIGHT_STYLES[back-double-quoted-argument]
if [[ \\\`\"\$ == *$arg[$i+1]* ]]; then
(( k += 1 )) # Color following char too.
(( i += 1 )) # Skip parsing the escaped char.
else
continue
fi
;;
*) continue ;;
esac
_zsh_highlight_main_add_region_highlight $j $k $style
done
}
# Highlight special chars inside dollar-quoted strings
_zsh_highlight_main_highlighter_highlight_dollar_string()
{
setopt localoptions noksharrays
local -a match mbegin mend
local MATCH; integer MBEGIN MEND
local i j k style
local AA
integer c
# Starting dollar-quote is at 1:2, so start parsing at offset 3 in the string.
for (( i = 3 ; i < end_pos - start_pos ; i += 1 )) ; do
(( j = i + start_pos - 1 ))
(( k = j + 1 ))
case "$arg[$i]" in
"\\") style=$ZSH_HIGHLIGHT_STYLES[back-dollar-quoted-argument]
for (( c = i + 1 ; c <= end_pos - start_pos ; c += 1 )); do
[[ "$arg[$c]" != ([0-9xXuUa-fA-F]) ]] && break
done
AA=$arg[$i+1,$c-1]
# Matching for HEX and OCT values like \0xA6, \xA6 or \012
if [[ "$AA" =~ "^(x|X)[0-9a-fA-F]{1,2}"
|| "$AA" =~ "^[0-7]{1,3}"
|| "$AA" =~ "^u[0-9a-fA-F]{1,4}"
|| "$AA" =~ "^U[0-9a-fA-F]{1,8}"
]]; then
(( k += $#MATCH ))
(( i += $#MATCH ))
else
if (( $#arg > $i+1 )) && [[ $arg[$i+1] == [xXuU] ]]; then
# \x not followed by hex digits is probably an error
style=$ZSH_HIGHLIGHT_STYLES[unknown-token]
fi
(( k += 1 )) # Color following char too.
(( i += 1 )) # Skip parsing the escaped char.
fi
;;
*) continue ;;
esac
_zsh_highlight_main_add_region_highlight $j $k $style
done
}
# Called with a single positional argument.
# Perform filename expansion (tilde expansion) on the argument and set $REPLY to the expanded value.
#
# Does not perform filename generation (globbing).
_zsh_highlight_main_highlighter_expand_path()
{
(( $# == 1 )) || echo "zsh-syntax-highlighting: BUG: _zsh_highlight_main_highlighter_expand_path: called without argument" >&2
# The $~1 syntax normally performs filename generation, but not when it's on the right-hand side of ${x:=y}.
setopt localoptions nonomatch
unset REPLY
: ${REPLY:=${(Q)~1}}
}