Fix issue where partial accept duplicates last word

When z-sy-h is enabled after autosuggestion widgets have already been
bound, partial accepting the last part of a suggestion will result in
that string being duplicated.

I was able to reproduce using the following versions of the two plugins:
- z-sy-h: dde84e1b25f059a298ce3189cddfd0778f998df3
- z-asug: ae315ded4dba10685dbbafbfa2ff3c1aefeb490d

and running the following commands interactively one after another:

```
zsh -df
% source path/to/zsh-autosuggestions.zsh
% source path/to/zsh-syntax-highlighting.zsh
% bindkey -e
% bindkey <alt-f>         # shows 'bindkey -e-e'
```

The order of the `source` statements matters and the issue cannot be
reproduced if the two source statements are executed together on one
line.

The problem is very similar to this one:
  https://github.com/zsh-users/zsh-autosuggestions/issues/126#issuecomment-217121315

See GitHub issue #483

.circleci/config.yml

@@ -0,0 +1,15 @@
+version: 2
+jobs:
+  build:
+    parallelism: 4
+    shell: /bin/bash --login
+    docker:
+    - image: ericfreese/zsh-autosuggestions-test:latest
+    steps:
+    - checkout
+    - run:
+        name: Running tests
+        command: |
+          for v in $(grep "^[^#]" ZSH_VERSIONS | awk "(NR + $CIRCLE_NODE_INDEX) % $CIRCLE_NODE_TOTAL == 0"); do
+            TEST_ZSH_BIN=zsh-$v make test || exit 1
+          done

.github/workflows/integration.yml

@@ -1,51 +0,0 @@
-on: [push, pull_request]
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
-  cancel-in-progress: true
-env:
-  IMAGE_CACHE_PATH: /tmp/.image-cache
-  IMAGE_CACHE_NAME: zsh-autosuggestions-test
-jobs:
-  determine-versions:
-    runs-on: ubuntu-22.04
-    outputs:
-      versions: ${{ steps.set-versions.outputs.versions }}
-    steps:
-    - uses: actions/checkout@v3
-    - id: set-versions
-      run: |
-        echo "versions=$(
-          grep "^[^#]" ZSH_VERSIONS \
-          | sed -E 's/(^|$)/"/g' \
-          | paste -sd ',' - \
-          | sed -e 's/^/[/' -e 's/$/]/'
-        )" >> $GITHUB_OUTPUT
-  test:
-    needs: determine-versions
-    runs-on: ubuntu-22.04
-    strategy:
-      matrix:
-        version: ${{ fromJson(needs.determine-versions.outputs.versions) }}
-    steps:
-    - uses: actions/checkout@v3
-    - name: Docker image cache
-      id: image-cache
-      uses: actions/cache@v3
-      with:
-        path: ${{ env.IMAGE_CACHE_PATH }}
-        key: image-cache-${{ matrix.version }}-${{ hashFiles('Dockerfile', 'install_test_zsh.sh', 'Gemfile.lock') }}
-    - name: Load cached docker image if available
-      if: ${{ steps.image-cache.outputs.cache-hit }}
-      run: gunzip < $IMAGE_CACHE_PATH/$IMAGE_CACHE_NAME.tar.gz | docker load
-    - name: Build the docker image if necessary
-      if: ${{ !steps.image-cache.outputs.cache-hit }}
-      run: |
-        docker build --build-arg TEST_ZSH_VERSION=${{ matrix.version }} -t $IMAGE_CACHE_NAME .
-        mkdir -p $IMAGE_CACHE_PATH
-        docker save $IMAGE_CACHE_NAME | gzip > $IMAGE_CACHE_PATH/$IMAGE_CACHE_NAME.tar.gz
-    - name: Run the tests
-      run: |
-        docker run --rm \
-          -v $PWD:/zsh-autosuggestions \
-          $IMAGE_CACHE_NAME \
-          make test

.gitignore

@@ -1,2 +0,0 @@
-# zsh word code files
-*.zwc

CHANGELOG.md

@@ -1,18 +1,5 @@
 # Changelog
 
-## v0.7.1
-- Clear POSTDISPLAY instead of unsetting (#634)
-- Always reset async file descriptor after consuming it (#630)
-- Always use builtin `exec` (#628)
-- Add `history-beginning-search-*-end` widgets to clear widget list (#619)
-- Switch CI from Circle CI to GitHub Actions
-
-## v0.7.0
-- Enable asynchronous mode by default (#498)
-- No longer wrap user widgets starting with `autosuggest-` prefix (#496)
-- Fix a bug wrapping widgets that modify the buffer (#541)
-
-
 ## v0.6.4
 - Fix `vi-forward-char` triggering a bell when using it to accept a suggestion (#488)
 - New configuration option to skip completion suggestions when buffer matches a pattern (#487)

Dockerfile

@@ -1,8 +1,5 @@
 FROM ruby:2.5.3-alpine
 
-ARG TEST_ZSH_VERSION
-RUN : "${TEST_ZSH_VERSION:?}"
-
 RUN apk add --no-cache autoconf
 RUN apk add --no-cache libtool
 RUN apk add --no-cache libcap-dev
@@ -14,8 +11,10 @@ RUN apk add --no-cache tmux
 
 WORKDIR /zsh-autosuggestions
 
-ADD install_test_zsh.sh ./
+ADD ZSH_VERSIONS /zsh-autosuggestions/ZSH_VERSIONS
+ADD install_test_zsh.sh /zsh-autosuggestions/install_test_zsh.sh
 RUN ./install_test_zsh.sh
 
-ADD Gemfile Gemfile.lock ./
+ADD Gemfile /zsh-autosuggestions/Gemfile
+ADD Gemfile.lock /zsh-autosuggestions/Gemfile.lock
 RUN bundle install

INSTALL.md

@@ -3,21 +3,19 @@
 * [Packages](#packages)
 * [Antigen](#antigen)
 * [Oh My Zsh](#oh-my-zsh)
-* [HomeBrew](#homebrew)
 * [Manual](#manual-git-clone)
 
 ## Packages
 
 | System  | Package |
 | ------------- | ------------- |
-| Alpine Linux | [zsh-autosuggestions](https://pkgs.alpinelinux.org/packages?name=zsh-autosuggestions) |
 | Debian / Ubuntu | [zsh-autosuggestions OBS repository](https://software.opensuse.org/download.html?project=shells%3Azsh-users%3Azsh-autosuggestions&package=zsh-autosuggestions) |
 | Fedora / CentOS / RHEL / Scientific Linux | [zsh-autosuggestions OBS repository](https://software.opensuse.org/download.html?project=shells%3Azsh-users%3Azsh-autosuggestions&package=zsh-autosuggestions) |
 | OpenSUSE / SLE | [zsh-autosuggestions OBS repository](https://software.opensuse.org/download.html?project=shells%3Azsh-users%3Azsh-autosuggestions&package=zsh-autosuggestions) |
 | Arch Linux / Manjaro / Antergos / Hyperbola | [zsh-autosuggestions](https://www.archlinux.org/packages/zsh-autosuggestions), [zsh-autosuggestions-git](https://aur.archlinux.org/packages/zsh-autosuggestions-git) |
-| NixOS | [zsh-autosuggestions](https://github.com/NixOS/nixpkgs/blob/master/pkgs/by-name/zs/zsh-autosuggestions/package.nix) |
+| NixOS | [zsh-autosuggestions](https://github.com/NixOS/nixpkgs/blob/master/pkgs/shells/zsh/zsh-autosuggestions/default.nix) |
 | Void Linux | [zsh-autosuggestions](https://github.com/void-linux/void-packages/blob/master/srcpkgs/zsh-autosuggestions/template) |
-| Mac OS | [homebrew](https://github.com/Homebrew/homebrew-core/blob/master/Formula/z/zsh-autosuggestions.rb)  |
+| Mac OS | [homebrew](https://github.com/Homebrew/homebrew-core/blob/master/Formula/zsh-autosuggestions.rb)  |
 | NetBSD | [pkgsrc](http://ftp.netbsd.org/pub/pkgsrc/current/pkgsrc/shells/zsh-autosuggestions/README.html)  |
 
 ## Antigen
@@ -41,25 +39,7 @@
 2. Add the plugin to the list of plugins for Oh My Zsh to load (inside `~/.zshrc`):
 
     ```sh
-    plugins=( 
-        # other plugins...
-        zsh-autosuggestions
-    )
-    ```
-
-3. Start a new terminal session.
-
-## Homebrew
-
-1. Install command: 
-    ```sh
-    brew install zsh-autosuggestions
-    ```
-
-2. To activate the autosuggestions, add the following at the end of your .zshrc: 
-    
-    ```sh
-    source $(brew --prefix)/share/zsh-autosuggestions/zsh-autosuggestions.zsh
+    plugins=(zsh-autosuggestions)
     ```
 
 3. Start a new terminal session.

LICENSE

@@ -1,5 +1,5 @@
 Copyright (c) 2013 Thiago de Arruda
-Copyright (c) 2016-2021 Eric Freese
+Copyright (c) 2016-2019 Eric Freese
 
 Permission is hereby granted, free of charge, to any person
 obtaining a copy of this software and associated documentation

README.md

@@ -6,6 +6,7 @@ It suggests commands as you type based on history and completions.
 
 Requirements: Zsh v4.3.11 or later
 
+[![CircleCI](https://img.shields.io/circleci/build/github/zsh-users/zsh-autosuggestions.svg)](https://circleci.com/gh/zsh-users/zsh-autosuggestions)
 [![Chat on Gitter](https://img.shields.io/gitter/room/zsh-users/zsh-autosuggestions.svg)](https://gitter.im/zsh-users/zsh-autosuggestions)
 
 <a href="https://asciinema.org/a/37390" target="_blank"><img src="https://asciinema.org/a/37390.png" width="400" /></a>
@@ -52,7 +53,7 @@ For more info, read the Character Highlighting section of the zsh manual: `man z
 `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:
 
 - `history`: Chooses the most recent match from history.
-- `completion`: Chooses a suggestion based on what tab-completion would suggest. (requires `zpty` module, which is included with zsh since 4.0.1)
+- `completion`: Chooses a suggestion based on what tab-completion would suggest. (requires `zpty` module)
 - `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`.
 
 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.
@@ -169,16 +170,18 @@ Tests are written in ruby using the [`rspec`](http://rspec.info/) framework. The
 
 Test files live in `spec/`. To run the tests, run `make test`. To run a specific test, run `TESTS=spec/some_spec.rb make test`. You can also specify a `zsh` binary to use by setting the `TEST_ZSH_BIN` environment variable (ex: `TEST_ZSH_BIN=/bin/zsh make test`).
 
-It's possible to run the tests for any supported version of zsh in a Docker image by building an image from the provided Dockerfile. To build the docker image for a specific version of zsh (where `<version>` below is substituted with the contents of a line from the [`ZSH_VERSIONS`](ZSH_VERSIONS) file), run:
+A docker image for testing is available [on docker hub](https://hub.docker.com/r/ericfreese/zsh-autosuggestions-test). It comes with ruby, the bundler dependencies, and all supported versions of zsh installed.
+
+Pull the docker image with:
 
 ```sh
-docker build --build-arg TEST_ZSH_VERSION=<version> -t zsh-autosuggestions-test .
+docker pull ericfreese/zsh-autosuggestions-test
 ```
 
-After building the image, run the tests via:
+To run the tests for a specific version of zsh (where `<version>` below is substituted with the contents of a line from the [`ZSH_VERSIONS`](ZSH_VERSIONS) file):
 
 ```sh
-docker run -it -v $PWD:/zsh-autosuggestions zsh-autosuggestions-test make test
+docker run -it -e TEST_ZSH_BIN=zsh-<version> -v $PWD:/zsh-autosuggestions zsh-autosuggestions-test make test
 ```
 
 

VERSION

@@ -1 +1 @@
-v0.7.1
+v0.6.4

ZSH_VERSIONS

@@ -1,5 +1,9 @@
 # Zsh releases to run tests against
 # See https://github.com/zsh-users/zsh/releases
+#
+# When modifying this file, rebuild and push docker image:
+#   $ docker build -t ericfreese/zsh-autosuggestions-test .
+#   $ docker push ericfreese/zsh-autosuggestions-test
 4.3.11
 5.0.2
 5.0.8
@@ -10,5 +14,3 @@
 5.5.1
 5.6.2
 5.7.1
-5.8.1
-5.9

install_test_zsh.sh

@@ -2,17 +2,19 @@
 
 set -ex
 
-mkdir zsh-build
-cd zsh-build
+for v in $(grep "^[^#]" ZSH_VERSIONS); do
+  mkdir zsh-$v
+  cd zsh-$v
 
-curl -L https://api.github.com/repos/zsh-users/zsh/tarball/zsh-$TEST_ZSH_VERSION | tar xz --strip=1
+  curl -L https://api.github.com/repos/zsh-users/zsh/tarball/zsh-$v | tar xz --strip=1
 
   ./Util/preconfig
   ./configure --enable-pcre \
               --enable-cap \
               --enable-multibyte \
               --with-term-lib='ncursesw tinfo' \
-            --with-tcsetpgrp
+              --with-tcsetpgrp \
+              --program-suffix="-$v"
 
   make install.bin
   make install.modules
@@ -20,4 +22,5 @@ make install.fns
 
   cd ..
 
-rm -rf zsh-build
+  rm -rf zsh-$v
+done

spec/multi_line_spec.rb

@@ -1,6 +1,11 @@
 describe 'a multi-line suggestion' do
   it 'should be displayed on multiple lines' do
-    with_history("echo \"\n\"") do
+    with_history(-> {
+      session.send_string('echo "')
+      session.send_keys('enter')
+      session.send_string('"')
+      session.send_keys('enter')
+    }) do
       session.send_keys('e')
       wait_for { session.content }.to eq("echo \"\n\"")
     end

spec/spec_helper.rb

@@ -1,7 +1,6 @@
 require 'pry'
 require 'rspec/wait'
 require 'terminal_session'
-require 'tempfile'
 
 RSpec.shared_context 'terminal session' do
   let(:term_opts) { {} }
@@ -22,12 +21,11 @@ RSpec.shared_context 'terminal session' do
   end
 
   def with_history(*commands, &block)
-    Tempfile.create do |f|
-      f.write(commands.map{|c| c.gsub("\n", "\\\n")}.join("\n"))
-      f.flush
-
     session.run_command('fc -p')
-      session.run_command("fc -R #{f.path}")
+
+    commands.each do |c|
+      c.respond_to?(:call) ? c.call : session.run_command(c)
+    end
 
     session.clear_screen
 
@@ -37,7 +35,6 @@ RSpec.shared_context 'terminal session' do
     session.run_command('fc -P')
   end
 end
-end
 
 RSpec.configure do |config|
   config.expect_with :rspec do |expectations|

spec/strategies/special_characters_helper.rb

@@ -1,71 +1,58 @@
 shared_examples 'special characters' do
-  describe 'a special character in the buffer should be treated like any other character' do
-    it 'asterisk' do
+  describe 'a special character in the buffer' do
+    it 'should be treated like any other character' do
       with_history('echo "hello*"', 'echo "hello."') do
         session.send_string('echo "hello*')
         wait_for { session.content }.to eq('echo "hello*"')
       end
-    end
 
-    it 'question mark' do
       with_history('echo "hello?"', 'echo "hello."') do
         session.send_string('echo "hello?')
         wait_for { session.content }.to eq('echo "hello?"')
       end
-    end
 
-    it 'backslash' do
       with_history('echo "hello\nworld"') do
         session.send_string('echo "hello\\')
         wait_for { session.content }.to eq('echo "hello\nworld"')
       end
-    end
 
-    it 'double backslash' do
       with_history('echo "\\\\"') do
         session.send_string('echo "\\\\')
         wait_for { session.content }.to eq('echo "\\\\"')
       end
-    end
 
-    it 'tilde' do
       with_history('echo ~/foo') do
         session.send_string('echo ~')
         wait_for { session.content }.to eq('echo ~/foo')
       end
-    end
 
-    it 'parentheses' do
       with_history('echo "$(ls foo)"') do
         session.send_string('echo "$(')
         wait_for { session.content }.to eq('echo "$(ls foo)"')
       end
-    end
 
-    it 'square bracket' do
       with_history('echo "$history[123]"') do
         session.send_string('echo "$history[')
         wait_for { session.content }.to eq('echo "$history[123]"')
         session.send_string('123]')
         wait_for { session.content }.to eq('echo "$history[123]"')
       end
-    end
 
-    it 'octothorpe' do
       with_history('echo "#yolo"') do
         session.send_string('echo "#')
         wait_for { session.content }.to eq('echo "#yolo"')
       end
+
+      with_history('echo "#foo"', 'echo $#abc') do
+        session.send_string('echo "#')
+        wait_for { session.content }.to eq('echo "#foo"')
       end
 
-    it 'caret' do
       with_history('echo "^A"', 'echo "^B"') do
         session.send_string('echo "^A')
         wait_for { session.content }.to eq('echo "^A"')
       end
-    end
 
-    it 'dash' do
       with_history('-foo() {}') do
         session.send_string('-')
         wait_for { session.content }.to eq('-foo() {}')

src/async.zsh

@@ -11,7 +11,7 @@ _zsh_autosuggest_async_request() {
 	# If we've got a pending request, cancel it
 	if [[ -n "$_ZSH_AUTOSUGGEST_ASYNC_FD" ]] && { true <&$_ZSH_AUTOSUGGEST_ASYNC_FD } 2>/dev/null; then
 		# Close the file descriptor and remove the handler
-		builtin exec {_ZSH_AUTOSUGGEST_ASYNC_FD}<&-
+		exec {_ZSH_AUTOSUGGEST_ASYNC_FD}<&-
 		zle -F $_ZSH_AUTOSUGGEST_ASYNC_FD
 
 		# We won't know the pid unless the user has zsh/system module installed
@@ -32,7 +32,7 @@ _zsh_autosuggest_async_request() {
 	fi
 
 	# Fork a process to fetch a suggestion and open a pipe to read from it
-	builtin exec {_ZSH_AUTOSUGGEST_ASYNC_FD}< <(
+	exec {_ZSH_AUTOSUGGEST_ASYNC_FD}< <(
 		# Tell parent process our pid
 		echo $sysparams[pid]
 
@@ -44,8 +44,7 @@ _zsh_autosuggest_async_request() {
 
 	# There's a weird bug here where ^C stops working unless we force a fork
 	# See https://github.com/zsh-users/zsh-autosuggestions/issues/364
-	autoload -Uz is-at-least
-	is-at-least 5.8 || command true
+	command true
 
 	# Read the pid from the child process
 	read _ZSH_AUTOSUGGEST_CHILD_PID <&$_ZSH_AUTOSUGGEST_ASYNC_FD
@@ -68,10 +67,9 @@ _zsh_autosuggest_async_response() {
 		zle autosuggest-suggest -- "$suggestion"
 
 		# Close the fd
-		builtin exec {1}<&-
+		exec {1}<&-
 	fi
 
 	# Always remove the handler
 	zle -F "$1"
-	_ZSH_AUTOSUGGEST_ASYNC_FD=
 }

src/config.zsh

@@ -28,8 +28,6 @@ typeset -g ZSH_AUTOSUGGEST_ORIGINAL_WIDGET_PREFIX=autosuggest-orig-
 		history-search-backward
 		history-beginning-search-forward
 		history-beginning-search-backward
-		history-beginning-search-forward-end
-		history-beginning-search-backward-end
 		history-substring-search-up
 		history-substring-search-down
 		up-line-or-beginning-search

src/widgets.zsh

@@ -30,7 +30,7 @@ _zsh_autosuggest_toggle() {
 # Clear the suggestion
 _zsh_autosuggest_clear() {
 	# Remove the suggestion
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	_zsh_autosuggest_invoke_original_widget $@
 }
@@ -47,7 +47,7 @@ _zsh_autosuggest_modify() {
 	local orig_postdisplay="$POSTDISPLAY"
 
 	# Clear suggestion while waiting for next one
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	# Original widget may modify the buffer
 	_zsh_autosuggest_invoke_original_widget $@
@@ -61,9 +61,20 @@ _zsh_autosuggest_modify() {
 		return $retval
 	fi
 
-	# Optimize if manually typing in the suggestion or if buffer hasn't changed
-	if [[ "$BUFFER" = "$orig_buffer"* && "$orig_postdisplay" = "${BUFFER:$#orig_buffer}"* ]]; then
-		POSTDISPLAY="${orig_postdisplay:$(($#BUFFER - $#orig_buffer))}"
+	# Optimize if manually typing in the suggestion
+	if (( $#BUFFER > $#orig_buffer )); then
+		local added=${BUFFER#$orig_buffer}
+
+		# If the string added matches the beginning of the postdisplay
+		if [[ "$added" = "${orig_postdisplay:0:$#added}" ]]; then
+			POSTDISPLAY="${orig_postdisplay:$#added}"
+			return $retval
+		fi
+	fi
+
+	# Don't fetch a new suggestion if the buffer hasn't changed
+	if [[ "$BUFFER" = "$orig_buffer" ]]; then
+		POSTDISPLAY="$orig_postdisplay"
 		return $retval
 	fi
 
@@ -102,7 +113,7 @@ _zsh_autosuggest_suggest() {
 	if [[ -n "$suggestion" ]] && (( $#BUFFER )); then
 		POSTDISPLAY="${suggestion#$BUFFER}"
 	else
-		POSTDISPLAY=
+		unset POSTDISPLAY
 	fi
 }
 
@@ -128,7 +139,7 @@ _zsh_autosuggest_accept() {
 	BUFFER="$BUFFER$POSTDISPLAY"
 
 	# Remove the suggestion
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	# Run the original widget before manually moving the cursor so that the
 	# cursor movement doesn't make the widget do something unexpected
@@ -151,7 +162,7 @@ _zsh_autosuggest_execute() {
 	BUFFER="$BUFFER$POSTDISPLAY"
 
 	# Remove the suggestion
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	# Call the original `accept-line` to handle syntax highlighting or
 	# other potential custom behavior
@@ -162,11 +173,13 @@ _zsh_autosuggest_execute() {
 _zsh_autosuggest_partial_accept() {
 	local -i retval cursor_loc
 
-	# Save the contents of the buffer so we can restore later if needed
+	# Save the original buffer/postdisplay so we can restore later if needed
 	local original_buffer="$BUFFER"
+	local original_postdisplay="$POSTDISPLAY"
 
 	# Temporarily accept the suggestion.
 	BUFFER="$BUFFER$POSTDISPLAY"
+	unset POSTDISPLAY
 
 	# Original widget moves the cursor
 	_zsh_autosuggest_invoke_original_widget $@
@@ -186,8 +199,9 @@ _zsh_autosuggest_partial_accept() {
 		# Clip the buffer at the cursor
 		BUFFER="${BUFFER[1,$cursor_loc]}"
 	else
-		# Restore the original buffer
+		# Restore the original buffer/postdisplay
 		BUFFER="$original_buffer"
+		POSTDISPLAY="$original_postdisplay"
 	fi
 
 	return $retval

zsh-autosuggestions.zsh

@@ -1,8 +1,8 @@
 # Fish-like fast/unobtrusive autosuggestions for zsh.
 # https://github.com/zsh-users/zsh-autosuggestions
-# v0.7.1
+# v0.6.4
 # Copyright (c) 2013 Thiago de Arruda
-# Copyright (c) 2016-2021 Eric Freese
+# Copyright (c) 2016-2019 Eric Freese
 # 
 # Permission is hereby granted, free of charge, to any person
 # obtaining a copy of this software and associated documentation
@@ -54,8 +54,6 @@ typeset -g ZSH_AUTOSUGGEST_ORIGINAL_WIDGET_PREFIX=autosuggest-orig-
 		history-search-backward
 		history-beginning-search-forward
 		history-beginning-search-backward
-		history-beginning-search-forward-end
-		history-beginning-search-backward-end
 		history-substring-search-up
 		history-substring-search-down
 		up-line-or-beginning-search
@@ -294,7 +292,7 @@ _zsh_autosuggest_toggle() {
 # Clear the suggestion
 _zsh_autosuggest_clear() {
 	# Remove the suggestion
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	_zsh_autosuggest_invoke_original_widget $@
 }
@@ -311,7 +309,7 @@ _zsh_autosuggest_modify() {
 	local orig_postdisplay="$POSTDISPLAY"
 
 	# Clear suggestion while waiting for next one
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	# Original widget may modify the buffer
 	_zsh_autosuggest_invoke_original_widget $@
@@ -325,9 +323,20 @@ _zsh_autosuggest_modify() {
 		return $retval
 	fi
 
-	# Optimize if manually typing in the suggestion or if buffer hasn't changed
-	if [[ "$BUFFER" = "$orig_buffer"* && "$orig_postdisplay" = "${BUFFER:$#orig_buffer}"* ]]; then
-		POSTDISPLAY="${orig_postdisplay:$(($#BUFFER - $#orig_buffer))}"
+	# Optimize if manually typing in the suggestion
+	if (( $#BUFFER > $#orig_buffer )); then
+		local added=${BUFFER#$orig_buffer}
+
+		# If the string added matches the beginning of the postdisplay
+		if [[ "$added" = "${orig_postdisplay:0:$#added}" ]]; then
+			POSTDISPLAY="${orig_postdisplay:$#added}"
+			return $retval
+		fi
+	fi
+
+	# Don't fetch a new suggestion if the buffer hasn't changed
+	if [[ "$BUFFER" = "$orig_buffer" ]]; then
+		POSTDISPLAY="$orig_postdisplay"
 		return $retval
 	fi
 
@@ -366,7 +375,7 @@ _zsh_autosuggest_suggest() {
 	if [[ -n "$suggestion" ]] && (( $#BUFFER )); then
 		POSTDISPLAY="${suggestion#$BUFFER}"
 	else
-		POSTDISPLAY=
+		unset POSTDISPLAY
 	fi
 }
 
@@ -392,7 +401,7 @@ _zsh_autosuggest_accept() {
 	BUFFER="$BUFFER$POSTDISPLAY"
 
 	# Remove the suggestion
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	# Run the original widget before manually moving the cursor so that the
 	# cursor movement doesn't make the widget do something unexpected
@@ -415,7 +424,7 @@ _zsh_autosuggest_execute() {
 	BUFFER="$BUFFER$POSTDISPLAY"
 
 	# Remove the suggestion
-	POSTDISPLAY=
+	unset POSTDISPLAY
 
 	# Call the original `accept-line` to handle syntax highlighting or
 	# other potential custom behavior
@@ -426,11 +435,13 @@ _zsh_autosuggest_execute() {
 _zsh_autosuggest_partial_accept() {
 	local -i retval cursor_loc
 
-	# Save the contents of the buffer so we can restore later if needed
+	# Save the original buffer/postdisplay so we can restore later if needed
 	local original_buffer="$BUFFER"
+	local original_postdisplay="$POSTDISPLAY"
 
 	# Temporarily accept the suggestion.
 	BUFFER="$BUFFER$POSTDISPLAY"
+	unset POSTDISPLAY
 
 	# Original widget moves the cursor
 	_zsh_autosuggest_invoke_original_widget $@
@@ -450,8 +461,9 @@ _zsh_autosuggest_partial_accept() {
 		# Clip the buffer at the cursor
 		BUFFER="${BUFFER[1,$cursor_loc]}"
 	else
-		# Restore the original buffer
+		# Restore the original buffer/postdisplay
 		BUFFER="$original_buffer"
+		POSTDISPLAY="$original_postdisplay"
 	fi
 
 	return $retval
@@ -768,7 +780,7 @@ _zsh_autosuggest_async_request() {
 	# If we've got a pending request, cancel it
 	if [[ -n "$_ZSH_AUTOSUGGEST_ASYNC_FD" ]] && { true <&$_ZSH_AUTOSUGGEST_ASYNC_FD } 2>/dev/null; then
 		# Close the file descriptor and remove the handler
-		builtin exec {_ZSH_AUTOSUGGEST_ASYNC_FD}<&-
+		exec {_ZSH_AUTOSUGGEST_ASYNC_FD}<&-
 		zle -F $_ZSH_AUTOSUGGEST_ASYNC_FD
 
 		# We won't know the pid unless the user has zsh/system module installed
@@ -789,7 +801,7 @@ _zsh_autosuggest_async_request() {
 	fi
 
 	# Fork a process to fetch a suggestion and open a pipe to read from it
-	builtin exec {_ZSH_AUTOSUGGEST_ASYNC_FD}< <(
+	exec {_ZSH_AUTOSUGGEST_ASYNC_FD}< <(
 		# Tell parent process our pid
 		echo $sysparams[pid]
 
@@ -801,8 +813,7 @@ _zsh_autosuggest_async_request() {
 
 	# There's a weird bug here where ^C stops working unless we force a fork
 	# See https://github.com/zsh-users/zsh-autosuggestions/issues/364
-	autoload -Uz is-at-least
-	is-at-least 5.8 || command true
+	command true
 
 	# Read the pid from the child process
 	read _ZSH_AUTOSUGGEST_CHILD_PID <&$_ZSH_AUTOSUGGEST_ASYNC_FD
@@ -825,12 +836,11 @@ _zsh_autosuggest_async_response() {
 		zle autosuggest-suggest -- "$suggestion"
 
 		# Close the fd
-		builtin exec {1}<&-
+		exec {1}<&-
 	fi
 
 	# Always remove the handler
 	zle -F "$1"
-	_ZSH_AUTOSUGGEST_ASYNC_FD=
 }
 
 #--------------------------------------------------------------------#