Merge pull request #330 from zsh-users/features/completion-suggestions

Features/completion suggestions

Makefile

@@ -9,6 +9,7 @@ SRC_FILES := \
 	$(SRC_DIR)/highlight.zsh \
 	$(SRC_DIR)/widgets.zsh \
 	$(SRC_DIR)/strategies/*.zsh \
+	$(SRC_DIR)/fetch.zsh \
 	$(SRC_DIR)/async.zsh \
 	$(SRC_DIR)/start.zsh
 

README.md

@@ -2,7 +2,7 @@
 
 _[Fish](http://fishshell.com/)-like fast/unobtrusive autosuggestions for zsh._
 
-It suggests commands as you type, based on command history.
+It suggests commands as you type.
 
 Requirements: Zsh v4.3.11 or later
 
@@ -39,10 +39,13 @@ Set `ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE` to configure the style that the suggestion
 
 ### Suggestion Strategy
 
-Set `ZSH_AUTOSUGGEST_STRATEGY` to choose the strategy for generating suggestions. There are currently two to choose from:
+`ZSH_AUTOSUGGEST_STRATEGY` is an array that specifies how suggestions should be generated. The strategies in the array are tried successively until a suggestion is found. There are currently three built-in strategies to choose from:
 
-- `default`: Chooses the most recent match.
-- `match_prev_cmd`: Chooses the most recent match whose preceding history item matches the most recently executed command ([more info](src/strategies/match_prev_cmd.zsh)). Note that this strategy won't work as expected with ZSH options that don't preserve the history order such as `HIST_IGNORE_ALL_DUPS` or `HIST_EXPIRE_DUPS_FIRST`.
+- `history`: Chooses the most recent match from history.
+- `match_prev_cmd`: Like `history`, but chooses the most recent match whose preceding history item matches the most recently executed command ([more info](src/strategies/match_prev_cmd.zsh)). Note that this strategy won't work as expected with ZSH options that don't preserve the history order such as `HIST_IGNORE_ALL_DUPS` or `HIST_EXPIRE_DUPS_FIRST`.
+- `completion`: (experimental) Chooses a suggestion based on what tab-completion would suggest.
+
+For example, setting `ZSH_AUTOSUGGEST_STRATEGY=(history completion)` will first try to find a suggestion from your history, but, if it can't find a match, will find a suggestion from the completion engine.
 
 
 ### Widget Mapping

spec/integrations/client_zpty_spec.rb

@@ -0,0 +1,14 @@
+describe 'a running zpty command' do
+  let(:before_sourcing) { -> { session.run_command('zmodload zsh/zpty && zpty -b kitty cat') } }
+
+  context 'when using `completion` strategy' do
+    let(:options) { ["ZSH_AUTOSUGGEST_STRATEGY=completion"] }
+
+    it 'is not affected' do
+      session.send_keys('a').send_keys('C-h')
+      session.run_command('zpty -t kitty; echo $?')
+
+      wait_for { session.content }.to end_with("\n0")
+    end
+  end
+end

spec/integrations/zle_input_stack_spec.rb

@@ -2,7 +2,7 @@ describe 'using `zle -U`' do
   let(:before_sourcing) do
     -> do
       session.
-        run_command('_zsh_autosuggest_strategy_test() { sleep 1; _zsh_autosuggest_strategy_default "$1" }').
+        run_command('_zsh_autosuggest_strategy_test() { sleep 1; _zsh_autosuggest_strategy_history "$1" }').
         run_command('foo() { zle -U - "echo hello" }; zle -N foo; bindkey ^B foo')
     end
   end

spec/options/strategy_spec.rb

@@ -1,20 +1,45 @@
 describe 'a suggestion for a given prefix' do
-  let(:options) { ['_zsh_autosuggest_strategy_default() { suggestion="echo foo" }'] }
+  let(:history_strategy) { '_zsh_autosuggest_strategy_history() { suggestion="history" }' }
+  let(:foobar_strategy) { '_zsh_autosuggest_strategy_foobar() { [[ "foobar baz" = $1* ]] && suggestion="foobar baz" }' }
+  let(:foobaz_strategy) { '_zsh_autosuggest_strategy_foobaz() { [[ "foobaz bar" = $1* ]] && suggestion="foobaz bar" }' }
 
-  it 'is determined by calling the default strategy function' do
-    session.send_string('e')
-    wait_for { session.content }.to eq('echo foo')
+  let(:options) { [ history_strategy ] }
+
+  it 'by default is determined by calling the `history` strategy function' do
+    session.send_string('h')
+    wait_for { session.content }.to eq('history')
   end
 
-  context 'when ZSH_AUTOSUGGEST_STRATEGY is set' do
+  context 'when ZSH_AUTOSUGGEST_STRATEGY is set to an array' do
     let(:options) { [
-      '_zsh_autosuggest_strategy_custom() { suggestion="echo foo" }',
-      'ZSH_AUTOSUGGEST_STRATEGY=custom'
+      foobar_strategy,
+      foobaz_strategy,
+      'ZSH_AUTOSUGGEST_STRATEGY=(foobar foobaz)'
     ] }
 
-    it 'is determined by calling the specified strategy function' do
-      session.send_string('e')
-      wait_for { session.content }.to eq('echo foo')
+    it 'is determined by the first strategy function to return a suggestion' do
+      session.send_string('foo')
+      wait_for { session.content }.to eq('foobar baz')
+
+      session.send_string('baz')
+      wait_for { session.content }.to eq('foobaz bar')
+    end
+  end
+
+  context 'when ZSH_AUTOSUGGEST_STRATEGY is set to a string' do
+    let(:options) { [
+      foobar_strategy,
+      foobaz_strategy,
+      'ZSH_AUTOSUGGEST_STRATEGY="foobar foobaz"'
+    ] }
+
+    it 'is determined by the first strategy function to return a suggestion' do
+      session.send_string('foo')
+      wait_for { session.content }.to eq('foobar baz')
+
+      session.send_string('baz')
+      wait_for { session.content }.to eq('foobaz bar')
     end
   end
 end
+

spec/strategies/completion_spec.rb

@@ -0,0 +1,26 @@
+describe 'the `completion` suggestion strategy' do
+  let(:options) { ['ZSH_AUTOSUGGEST_STRATEGY=completion'] }
+  let(:before_sourcing) do
+    -> do
+      session.
+        run_command('autoload compinit && compinit').
+        run_command('_foo() { compadd bar }').
+        run_command('compdef _foo baz')
+    end
+  end
+
+  it 'suggests the first completion result' do
+    session.send_string('baz ')
+    wait_for { session.content }.to eq('baz bar')
+  end
+
+  context 'when async mode is enabled' do
+    let(:options) { ['ZSH_AUTOSUGGEST_USE_ASYNC=true', 'ZSH_AUTOSUGGEST_STRATEGY=completion'] }
+
+    it 'suggests the first completion result' do
+      session.send_string('baz ')
+      wait_for { session.content }.to eq('baz bar')
+    end
+  end
+end
+

spec/strategies/history_spec.rb

@@ -1,6 +1,6 @@
 require 'strategies/special_characters_helper'
 
-describe 'the default suggestion strategy' do
+describe 'the `history` suggestion strategy' do
   it 'suggests the last matching history entry' do
     with_history('ls foo', 'ls bar', 'echo baz') do
       session.send_string('ls')

spec/strategies/match_prev_cmd_spec.rb

@@ -1,6 +1,6 @@
 require 'strategies/special_characters_helper'
 
-describe 'the match_prev_cmd strategy' do
+describe 'the `match_prev_cmd` strategy' do
   let(:options) { ['ZSH_AUTOSUGGEST_STRATEGY=match_prev_cmd'] }
 
   it 'suggests the last matching history entry after the previous command' do

src/config.zsh

@@ -11,7 +11,9 @@ ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE='fg=8'
 # Prefix to use when saving original versions of bound widgets
 ZSH_AUTOSUGGEST_ORIGINAL_WIDGET_PREFIX=autosuggest-orig-
 
-ZSH_AUTOSUGGEST_STRATEGY=default
+# Strategies to use to fetch a suggestion
+# Will try each strategy in order until a suggestion is returned
+ZSH_AUTOSUGGEST_STRATEGY=(history)
 
 # Widgets that clear the suggestion
 ZSH_AUTOSUGGEST_CLEAR_WIDGETS=(
@@ -68,4 +70,7 @@ 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/fetch.zsh

@@ -0,0 +1,24 @@
+
+#--------------------------------------------------------------------#
+# Fetch Suggestion                                                   #
+#--------------------------------------------------------------------#
+# Loops through all specified strategies and returns a suggestion
+# from the first strategy to provide one.
+#
+
+_zsh_autosuggest_fetch_suggestion() {
+	typeset -g suggestion
+	local -a strategies
+	local strategy
+
+	# Ensure we are working with an array
+	strategies=(${=ZSH_AUTOSUGGEST_STRATEGY})
+
+	for strategy in $strategies; do
+		# Try to get a suggestion from this strategy
+		_zsh_autosuggest_strategy_$strategy "$1"
+
+		# Break once we've found a suggestion
+		[[ -n "$suggestion" ]] && break
+	done
+}

src/strategies/completion.zsh

@@ -0,0 +1,124 @@
+
+#--------------------------------------------------------------------#
+# Completion Suggestion Strategy                                     #
+#--------------------------------------------------------------------#
+# Fetches suggestions from zsh's completion engine
+# Based on https://github.com/Valodim/zsh-capture-completion
+#
+
+_zsh_autosuggest_capture_setup() {
+	zmodload zsh/zutil # For `zparseopts`
+
+	# Ensure completions have been initialized
+	if ! whence compdef >/dev/null; then
+		autoload -Uz compinit && compinit
+	fi
+
+	# There is a bug in zpty module (fixed in zsh/master) by which a
+	# zpty that exits will kill all zpty processes that were forked
+	# before it. Here we set up a zsh exit hook to SIGKILL the zpty
+	# process immediately, before it has a chance to kill any other
+	# zpty processes.
+	zshexit() {
+		kill -KILL $$
+		sleep 1 # Block for long enough for the signal to come through
+	}
+
+	# Never group stuff!
+	zstyle ':completion:*' list-grouped false
+
+	# No list separator, this saves some stripping later on
+	zstyle ':completion:*' list-separator ''
+
+	# Override compadd (this is our hook)
+	compadd () {
+		setopt localoptions norcexpandparam
+
+		# Just delegate and leave if any of -O, -A or -D are given
+		if [[ ${@[1,(i)(-|--)]} == *-(O|A|D)\ * ]]; then
+			builtin compadd "$@"
+			return $?
+		fi
+
+		# Capture completions by injecting -A parameter into the compadd call.
+		# This takes care of matching for us.
+		typeset -a __hits
+		builtin compadd -A __hits "$@"
+
+		# Exit if no completion results
+		[[ -n $__hits ]] || return
+
+		# 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
+
+		# Print the first match
+		echo -nE - $'\0'$IPREFIX$apre$hpre$__hits[1]$dsuf$hsuf$asuf$'\0'
+	}
+}
+
+_zsh_autosuggest_capture_widget() {
+	_zsh_autosuggest_capture_setup
+
+	zle complete-word
+}
+
+zle -N autosuggest-capture-completion _zsh_autosuggest_capture_widget
+
+_zsh_autosuggest_capture_buffer() {
+	local BUFFERCONTENT="$1"
+
+	_zsh_autosuggest_capture_setup
+
+	zmodload zsh/parameter # For `$functions`
+
+	# Make vared completion work as if for a normal command line
+	# https://stackoverflow.com/a/7057118/154703
+	autoload +X _complete
+	functions[_original_complete]=$functions[_complete]
+	_complete () {
+		unset 'compstate[vared]'
+		_original_complete "$@"
+	}
+
+	# Open zle with buffer set so we can capture completions for it
+	vared BUFFERCONTENT
+}
+
+_zsh_autosuggest_capture_completion() {
+	typeset -g completion
+	local line REPLY
+
+	# Zle will be inactive if we are in async mode
+	if zle; then
+		zpty $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME zle autosuggest-capture-completion
+	else
+		zpty $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME _zsh_autosuggest_capture_buffer "\$1"
+		zpty -w $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME $'\t'
+	fi
+
+	# The completion result is surrounded by null bytes, so read the
+	# content between the first two null bytes.
+	zpty -r $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME line '*'$'\0''*'$'\0'
+
+	# On older versions of zsh, we sometimes get extra bytes after the
+	# second null byte, so trim those off the end
+	completion="${${${(M)line:#*$'\0'*$'\0'*}#*$'\0'}%%$'\0'*}"
+
+	# Destroy the pty
+	zpty -d $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME
+}
+
+_zsh_autosuggest_strategy_completion() {
+	typeset -g suggestion
+	local completion
+
+	# Fetch the first completion result
+	_zsh_autosuggest_capture_completion "$1"
+
+	# Add the completion string to the buffer to build the full suggestion
+	local -i i=1
+	while [[ "$completion" != "${1[$i,-1]}"* ]]; do ((i++)); done
+	suggestion="${1[1,$i-1]}$completion"
+}

src/strategies/history.zsh

@@ -1,12 +1,12 @@
 
 #--------------------------------------------------------------------#
-# Default Suggestion Strategy                                        #
+# History Suggestion Strategy                                        #
 #--------------------------------------------------------------------#
 # Suggests the most recent history item that matches the given
 # prefix.
 #
 
-_zsh_autosuggest_strategy_default() {
+_zsh_autosuggest_strategy_history() {
 	# Reset options to defaults and enable LOCAL_OPTIONS
 	emulate -L zsh
 

src/widgets.zsh

@@ -97,7 +97,7 @@ _zsh_autosuggest_fetch() {
 		_zsh_autosuggest_async_request "$BUFFER"
 	else
 		local suggestion
-		_zsh_autosuggest_strategy_$ZSH_AUTOSUGGEST_STRATEGY "$BUFFER"
+		_zsh_autosuggest_fetch_suggestion "$BUFFER"
 		_zsh_autosuggest_suggest "$suggestion"
 	fi
 }

zsh-autosuggestions.zsh

@@ -47,7 +47,9 @@ ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE='fg=8'
 # Prefix to use when saving original versions of bound widgets
 ZSH_AUTOSUGGEST_ORIGINAL_WIDGET_PREFIX=autosuggest-orig-
 
-ZSH_AUTOSUGGEST_STRATEGY=default
+# Strategies to use to fetch a suggestion
+# Will try each strategy in order until a suggestion is returned
+ZSH_AUTOSUGGEST_STRATEGY=(history)
 
 # Widgets that clear the suggestion
 ZSH_AUTOSUGGEST_CLEAR_WIDGETS=(
@@ -104,7 +106,10 @@ 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                                                  #
@@ -378,7 +383,7 @@ _zsh_autosuggest_fetch() {
 		_zsh_autosuggest_async_request "$BUFFER"
 	else
 		local suggestion
-		_zsh_autosuggest_strategy_$ZSH_AUTOSUGGEST_STRATEGY "$BUFFER"
+		_zsh_autosuggest_fetch_suggestion "$BUFFER"
 		_zsh_autosuggest_suggest "$suggestion"
 	fi
 }
@@ -494,13 +499,137 @@ zle -N autosuggest-disable _zsh_autosuggest_widget_disable
 zle -N autosuggest-toggle _zsh_autosuggest_widget_toggle
 
 #--------------------------------------------------------------------#
-# Default Suggestion Strategy                                        #
+# Completion Suggestion Strategy                                     #
+#--------------------------------------------------------------------#
+# Fetches suggestions from zsh's completion engine
+# Based on https://github.com/Valodim/zsh-capture-completion
+#
+
+_zsh_autosuggest_capture_setup() {
+	zmodload zsh/zutil # For `zparseopts`
+
+	# Ensure completions have been initialized
+	if ! whence compdef >/dev/null; then
+		autoload -Uz compinit && compinit
+	fi
+
+	# There is a bug in zpty module (fixed in zsh/master) by which a
+	# zpty that exits will kill all zpty processes that were forked
+	# before it. Here we set up a zsh exit hook to SIGKILL the zpty
+	# process immediately, before it has a chance to kill any other
+	# zpty processes.
+	zshexit() {
+		kill -KILL $$
+		sleep 1 # Block for long enough for the signal to come through
+	}
+
+	# Never group stuff!
+	zstyle ':completion:*' list-grouped false
+
+	# No list separator, this saves some stripping later on
+	zstyle ':completion:*' list-separator ''
+
+	# Override compadd (this is our hook)
+	compadd () {
+		setopt localoptions norcexpandparam
+
+		# Just delegate and leave if any of -O, -A or -D are given
+		if [[ ${@[1,(i)(-|--)]} == *-(O|A|D)\ * ]]; then
+			builtin compadd "$@"
+			return $?
+		fi
+
+		# Capture completions by injecting -A parameter into the compadd call.
+		# This takes care of matching for us.
+		typeset -a __hits
+		builtin compadd -A __hits "$@"
+
+		# Exit if no completion results
+		[[ -n $__hits ]] || return
+
+		# 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
+
+		# Print the first match
+		echo -nE - $'\0'$IPREFIX$apre$hpre$__hits[1]$dsuf$hsuf$asuf$'\0'
+	}
+}
+
+_zsh_autosuggest_capture_widget() {
+	_zsh_autosuggest_capture_setup
+
+	zle complete-word
+}
+
+zle -N autosuggest-capture-completion _zsh_autosuggest_capture_widget
+
+_zsh_autosuggest_capture_buffer() {
+	local BUFFERCONTENT="$1"
+
+	_zsh_autosuggest_capture_setup
+
+	zmodload zsh/parameter # For `$functions`
+
+	# Make vared completion work as if for a normal command line
+	# https://stackoverflow.com/a/7057118/154703
+	autoload +X _complete
+	functions[_original_complete]=$functions[_complete]
+	_complete () {
+		unset 'compstate[vared]'
+		_original_complete "$@"
+	}
+
+	# Open zle with buffer set so we can capture completions for it
+	vared BUFFERCONTENT
+}
+
+_zsh_autosuggest_capture_completion() {
+	typeset -g completion
+	local line REPLY
+
+	# Zle will be inactive if we are in async mode
+	if zle; then
+		zpty $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME zle autosuggest-capture-completion
+	else
+		zpty $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME _zsh_autosuggest_capture_buffer "\$1"
+		zpty -w $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME $'\t'
+	fi
+
+	# The completion result is surrounded by null bytes, so read the
+	# content between the first two null bytes.
+	zpty -r $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME line '*'$'\0''*'$'\0'
+
+	# On older versions of zsh, we sometimes get extra bytes after the
+	# second null byte, so trim those off the end
+	completion="${${${(M)line:#*$'\0'*$'\0'*}#*$'\0'}%%$'\0'*}"
+
+	# Destroy the pty
+	zpty -d $ZSH_AUTOSUGGEST_COMPLETIONS_PTY_NAME
+}
+
+_zsh_autosuggest_strategy_completion() {
+	typeset -g suggestion
+	local completion
+
+	# Fetch the first completion result
+	_zsh_autosuggest_capture_completion "$1"
+
+	# Add the completion string to the buffer to build the full suggestion
+	local -i i=1
+	while [[ "$completion" != "${1[$i,-1]}"* ]]; do ((i++)); done
+	suggestion="${1[1,$i-1]}$completion"
+}
+
+#--------------------------------------------------------------------#
+# History Suggestion Strategy                                        #
 #--------------------------------------------------------------------#
 # Suggests the most recent history item that matches the given
 # prefix.
 #
 
-_zsh_autosuggest_strategy_default() {
+_zsh_autosuggest_strategy_history() {
 	# Reset options to defaults and enable LOCAL_OPTIONS
 	emulate -L zsh
 
@@ -577,6 +706,30 @@ _zsh_autosuggest_strategy_match_prev_cmd() {
 	typeset -g suggestion="$history[$histkey]"
 }
 
+#--------------------------------------------------------------------#
+# Fetch Suggestion                                                   #
+#--------------------------------------------------------------------#
+# Loops through all specified strategies and returns a suggestion
+# from the first strategy to provide one.
+#
+
+_zsh_autosuggest_fetch_suggestion() {
+	typeset -g suggestion
+	local -a strategies
+	local strategy
+
+	# Ensure we are working with an array
+	strategies=(${=ZSH_AUTOSUGGEST_STRATEGY})
+
+	for strategy in $strategies; do
+		# Try to get a suggestion from this strategy
+		_zsh_autosuggest_strategy_$strategy "$1"
+
+		# Break once we've found a suggestion
+		[[ -n "$suggestion" ]] && break
+	done
+}
+
 #--------------------------------------------------------------------#
 # Async                                                              #
 #--------------------------------------------------------------------#