First pass at getting suggestions from completion engine (#111)

Uses https://github.com/Valodim/zsh-capture-completion with some slight
modifications.

src/config.zsh

@@ -68,4 +68,7 @@ ZSH_AUTOSUGGEST_IGNORE_WIDGETS=(
 ZSH_AUTOSUGGEST_BUFFER_MAX_SIZE=
 
 # Pty name for calculating autosuggestions asynchronously
-ZSH_AUTOSUGGEST_ASYNC_PTY_NAME=zsh_autosuggest_pty
+ZSH_AUTOSUGGEST_ASYNC_PTY_NAME=zsh_autosuggest_async_pty
+
+# Pty name for capturing completions for completion suggestion strategy
+ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME=zsh_autosuggest_completion_pty

src/strategies/completion.zsh

@@ -0,0 +1,132 @@
+
+#--------------------------------------------------------------------#
+# Completion Suggestion Strategy                                     #
+#--------------------------------------------------------------------#
+# Fetches suggestions from zsh's completion engine
+#
+
+# Big thanks to https://github.com/Valodim/zsh-capture-completion
+_zsh_autosuggest_capture_completion() {
+	zpty $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME zsh -f -i
+
+	# line buffer for pty output
+	local line
+
+	setopt rcquotes
+	() {
+		zpty -w $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME source $1
+		repeat 4; do
+			zpty -r $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME line
+			[[ $line == ok* ]] && return
+		done
+		echo 'error initializing.' >&2
+		exit 2
+	} =( <<< '
+	# no prompt!
+	PROMPT=
+	# load completion system
+	autoload compinit
+	compinit -d ~/.zcompdump_autosuggestions
+	# never run a command
+	bindkey ''^M'' undefined
+	bindkey ''^J'' undefined
+	bindkey ''^I'' complete-word
+	# send a line with null-byte at the end before and after completions are output
+	null-line () {
+		echo -E - $''\0''
+	}
+	compprefuncs=( null-line )
+	comppostfuncs=( null-line exit )
+	# never group stuff!
+	zstyle '':completion:*'' list-grouped false
+	# don''t insert tab when attempting completion on empty line
+	zstyle '':completion:*'' insert-tab false
+	# no list separator, this saves some stripping later on
+	zstyle '':completion:*'' list-separator ''''
+	# we use zparseopts
+	zmodload zsh/zutil
+	# override compadd (this our hook)
+	compadd () {
+		# check if any of -O, -A or -D are given
+		if [[ ${@[1,(i)(-|--)]} == *-(O|A|D)\ * ]]; then
+			# if that is the case, just delegate and leave
+			builtin compadd "$@"
+			return $?
+		fi
+		# ok, this concerns us!
+		# echo -E - got this: "$@"
+		# be careful with namespacing here, we don''t want to mess with stuff that
+		# should be passed to compadd!
+		typeset -a __hits __dscr __tmp
+		# do we have a description parameter?
+		# note we don''t use zparseopts here because of combined option parameters
+		# with arguments like -default- confuse it.
+		if (( $@[(I)-d] )); then # kind of a hack, $+@[(r)-d] doesn''t work because of line noise overload
+			# next param after -d
+			__tmp=${@[$[${@[(i)-d]}+1]]}
+			# description can be given as an array parameter name, or inline () array
+			if [[ $__tmp == \(* ]]; then
+				eval "__dscr=$__tmp"
+			else
+				__dscr=( "${(@P)__tmp}" )
+			fi
+		fi
+		# capture completions by injecting -A parameter into the compadd call.
+		# this takes care of matching for us.
+		builtin compadd -A __hits -D __dscr "$@"
+		# JESUS CHRIST IT TOOK ME FOREVER TO FIGURE OUT THIS OPTION WAS SET AND WAS MESSING WITH MY SHIT HERE
+		setopt localoptions norcexpandparam extendedglob
+		# extract prefixes and suffixes from compadd call. we can''t do zsh''s cool
+		# -r remove-func magic, but it''s better than nothing.
+		typeset -A apre hpre hsuf asuf
+		zparseopts -E P:=apre p:=hpre S:=asuf s:=hsuf
+		# append / to directories? we are only emulating -f in a half-assed way
+		# here, but it''s better than nothing.
+		integer dirsuf=0
+		# don''t be fooled by -default- >.>
+		if [[ -z $hsuf && "${${@//-default-/}% -# *}" == *-[[:alnum:]]#f* ]]; then
+			dirsuf=1
+		fi
+		# just drop
+		[[ -n $__hits ]] || return
+		# this is the point where we have all matches in $__hits and all
+		# descriptions in $__dscr!
+		# display all matches
+		local dsuf dscr
+		for i in {1..$#__hits}; do
+			# add a dir suffix?
+			(( dirsuf )) && [[ -d $__hits[$i] ]] && dsuf=/ || dsuf=
+			# description to be displayed afterwards
+			(( $#__dscr >= $i )) && dscr=" -- ${${__dscr[$i]}##$__hits[$i] #}" || dscr=
+			echo -E - $IPREFIX$apre$hpre$__hits[$i]$dsuf$hsuf$asuf
+		done
+	}
+	# signal success!
+	echo ok')
+
+	zpty -w $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME "$*"$'\t'
+
+	integer tog=0
+	# read from the pty, and parse linewise
+	while zpty -r $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME; do :; done | while IFS= read -r line; do
+		if [[ $line == *$'\0\r' ]]; then
+			(( tog++ )) && return 0 || continue
+		fi
+		# display between toggles
+		(( tog )) && echo -E - $line
+	done
+
+	return 2
+}
+
+_zsh_autosuggest_strategy_completion() {
+	typeset -g suggestion=$(_zsh_autosuggest_capture_completion "$1" | head -n 1)
+
+	# Strip the trailing carriage return
+	suggestion="${suggestion%$'\r'}"
+
+	# Add the completion string to the buffer to build the full suggestion
+	local -i i=1
+	while [[ "$suggestion" != "${1[$i,-1]}"* ]]; do ((i++)); done
+	suggestion="${1[1,$i-1]}$suggestion"
+}

zsh-autosuggestions.zsh

@@ -104,7 +104,10 @@ ZSH_AUTOSUGGEST_IGNORE_WIDGETS=(
 ZSH_AUTOSUGGEST_BUFFER_MAX_SIZE=
 
 # Pty name for calculating autosuggestions asynchronously
-ZSH_AUTOSUGGEST_ASYNC_PTY_NAME=zsh_autosuggest_pty
+ZSH_AUTOSUGGEST_ASYNC_PTY_NAME=zsh_autosuggest_async_pty
+
+# Pty name for capturing completions for completion suggestion strategy
+ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME=zsh_autosuggest_completion_pty
 
 #--------------------------------------------------------------------#
 # Utility Functions                                                  #
@@ -493,6 +496,138 @@ zle -N autosuggest-enable _zsh_autosuggest_widget_enable
 zle -N autosuggest-disable _zsh_autosuggest_widget_disable
 zle -N autosuggest-toggle _zsh_autosuggest_widget_toggle
 
+#--------------------------------------------------------------------#
+# Completion Suggestion Strategy                                     #
+#--------------------------------------------------------------------#
+# Fetches suggestions from zsh's completion engine
+#
+
+# Big thanks to https://github.com/Valodim/zsh-capture-completion
+_zsh_autosuggest_capture_completion() {
+	zpty $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME zsh -f -i
+
+	# line buffer for pty output
+	local line
+
+	setopt rcquotes
+	() {
+		zpty -w $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME source $1
+		repeat 4; do
+			zpty -r $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME line
+			[[ $line == ok* ]] && return
+		done
+		echo 'error initializing.' >&2
+		exit 2
+	} =( <<< '
+	# no prompt!
+	PROMPT=
+	# load completion system
+	autoload compinit
+	compinit -d ~/.zcompdump_autosuggestions
+	# never run a command
+	bindkey ''^M'' undefined
+	bindkey ''^J'' undefined
+	bindkey ''^I'' complete-word
+	# send a line with null-byte at the end before and after completions are output
+	null-line () {
+		echo -E - $''\0''
+	}
+	compprefuncs=( null-line )
+	comppostfuncs=( null-line exit )
+	# never group stuff!
+	zstyle '':completion:*'' list-grouped false
+	# don''t insert tab when attempting completion on empty line
+	zstyle '':completion:*'' insert-tab false
+	# no list separator, this saves some stripping later on
+	zstyle '':completion:*'' list-separator ''''
+	# we use zparseopts
+	zmodload zsh/zutil
+	# override compadd (this our hook)
+	compadd () {
+		# check if any of -O, -A or -D are given
+		if [[ ${@[1,(i)(-|--)]} == *-(O|A|D)\ * ]]; then
+			# if that is the case, just delegate and leave
+			builtin compadd "$@"
+			return $?
+		fi
+		# ok, this concerns us!
+		# echo -E - got this: "$@"
+		# be careful with namespacing here, we don''t want to mess with stuff that
+		# should be passed to compadd!
+		typeset -a __hits __dscr __tmp
+		# do we have a description parameter?
+		# note we don''t use zparseopts here because of combined option parameters
+		# with arguments like -default- confuse it.
+		if (( $@[(I)-d] )); then # kind of a hack, $+@[(r)-d] doesn''t work because of line noise overload
+			# next param after -d
+			__tmp=${@[$[${@[(i)-d]}+1]]}
+			# description can be given as an array parameter name, or inline () array
+			if [[ $__tmp == \(* ]]; then
+				eval "__dscr=$__tmp"
+			else
+				__dscr=( "${(@P)__tmp}" )
+			fi
+		fi
+		# capture completions by injecting -A parameter into the compadd call.
+		# this takes care of matching for us.
+		builtin compadd -A __hits -D __dscr "$@"
+		# JESUS CHRIST IT TOOK ME FOREVER TO FIGURE OUT THIS OPTION WAS SET AND WAS MESSING WITH MY SHIT HERE
+		setopt localoptions norcexpandparam extendedglob
+		# extract prefixes and suffixes from compadd call. we can''t do zsh''s cool
+		# -r remove-func magic, but it''s better than nothing.
+		typeset -A apre hpre hsuf asuf
+		zparseopts -E P:=apre p:=hpre S:=asuf s:=hsuf
+		# append / to directories? we are only emulating -f in a half-assed way
+		# here, but it''s better than nothing.
+		integer dirsuf=0
+		# don''t be fooled by -default- >.>
+		if [[ -z $hsuf && "${${@//-default-/}% -# *}" == *-[[:alnum:]]#f* ]]; then
+			dirsuf=1
+		fi
+		# just drop
+		[[ -n $__hits ]] || return
+		# this is the point where we have all matches in $__hits and all
+		# descriptions in $__dscr!
+		# display all matches
+		local dsuf dscr
+		for i in {1..$#__hits}; do
+			# add a dir suffix?
+			(( dirsuf )) && [[ -d $__hits[$i] ]] && dsuf=/ || dsuf=
+			# description to be displayed afterwards
+			(( $#__dscr >= $i )) && dscr=" -- ${${__dscr[$i]}##$__hits[$i] #}" || dscr=
+			echo -E - $IPREFIX$apre$hpre$__hits[$i]$dsuf$hsuf$asuf
+		done
+	}
+	# signal success!
+	echo ok')
+
+	zpty -w $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME "$*"$'\t'
+
+	integer tog=0
+	# read from the pty, and parse linewise
+	while zpty -r $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME; do :; done | while IFS= read -r line; do
+		if [[ $line == *$'\0\r' ]]; then
+			(( tog++ )) && return 0 || continue
+		fi
+		# display between toggles
+		(( tog )) && echo -E - $line
+	done
+
+	return 2
+}
+
+_zsh_autosuggest_strategy_completion() {
+	typeset -g suggestion=$(_zsh_autosuggest_capture_completion "$1" | head -n 1)
+
+	# Strip the trailing carriage return
+	suggestion="${suggestion%$'\r'}"
+
+	# Add the completion string to the buffer to build the full suggestion
+	local -i i=1
+	while [[ "$suggestion" != "${1[$i,-1]}"* ]]; do ((i++)); done
+	suggestion="${1[1,$i-1]}$suggestion"
+}
+
 #--------------------------------------------------------------------#
 # Default Suggestion Strategy                                        #
 #--------------------------------------------------------------------#