As you type commands, you will see a completion offered after the cursor in a muted gray color. This color can be changed by setting the `ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE` variable. See [configuration](#configuration).
If you press the <kbd>→</kbd> key (`forward-char` widget) or <kbd>End</kbd> (`end-of-line` widget) with the cursor at the end of the buffer, it will accept the suggestion, replacing the contents of the command line buffer with the suggestion.
**Note:** If you are using Oh My Zsh, you can put this configuration in a file in the `$ZSH_CUSTOM` directory. See their comments on [overriding internals](https://github.com/robbyrussell/oh-my-zsh/wiki/Customization#overriding-internals).
Set `ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE` to configure the style that the suggestion is shown with. The default is `fg=8`, which will set the foreground color to color 8 from the [256-color palette](https://upload.wikimedia.org/wikipedia/commons/1/15/Xterm_256color_chart.svg). If your terminal only supports 8 colors, you will need to use a number between 0 and 7.
Background color can also be set, and the suggestion can be styled bold, underlined, or standout. For example, this would show suggestions with bold, underlined, pink text on a cyan background:
For more info, read the Character Highlighting section of the zsh manual: `man zshzle` or [online](http://zsh.sourceforge.net/Doc/Release/Zsh-Line-Editor.html#Character-Highlighting).
**Note:** Some iTerm2 users have reported [not being able to see the suggestions](https://github.com/zsh-users/zsh-autosuggestions/issues/416#issuecomment-486516333). If this affects you, the problem is likely caused by incorrect color settings. In order to correct this, go into iTerm2's setting, navigate to profile > colors and make sure that the colors for Basic Colors > Background and ANSI Colors > Bright Black are **different**.
`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:
-`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.
This plugin works by triggering custom behavior when certain [zle widgets](http://zsh.sourceforge.net/Doc/Release/Zsh-Line-Editor.html#Zle-Widgets) are invoked. You can add and remove widgets from these arrays to change the behavior of this plugin:
Set `ZSH_AUTOSUGGEST_BUFFER_MAX_SIZE` to an integer value to disable autosuggestion for large buffers. The default is unset, which means that autosuggestion will be tried for any buffer size. Recommended value is 20.
Suggestions are fetched asynchronously by default in zsh versions 5.0.8 and greater. To disable asynchronous suggestions and fetch them synchronously instead, `unset ZSH_AUTOSUGGEST_USE_ASYNC` after sourcing the plugin.
Alternatively, if you are using a version of zsh older than 5.0.8 and want to enable asynchronous mode, set the `ZSH_AUTOSUGGEST_USE_ASYNC` variable after sourcing the plugin (it can be set to anything). Note that there is [a bug](https://github.com/zsh-users/zsh-autosuggestions/issues/364#issuecomment-481423232) in versions of zsh older than 5.0.8 where <kbd>ctrl</kbd> + <kbd>c</kbd> will fail to reset the prompt immediately after fetching a suggestion asynchronously.
Set `ZSH_AUTOSUGGEST_MANUAL_REBIND` (it can be set to anything) to disable automatic widget re-binding on each precmd. This can be a big boost to performance, but you'll need to handle re-binding yourself if any of the widget lists change or if you or another plugin wrap any of the autosuggest widgets. To re-bind widgets, run `_zsh_autosuggest_bind_widgets`.
Set `ZSH_AUTOSUGGEST_HISTORY_IGNORE` to a [glob pattern](http://zsh.sourceforge.net/Doc/Release/Expansion.html#Glob-Operators) to prevent offering suggestions for history entries that match the pattern. For example, set it to `"cd *"` to never suggest any `cd` commands from history. Or set to `"?(#c50,)"` to never suggest anything 50 characters or longer.
Set `ZSH_AUTOSUGGEST_COMPLETION_IGNORE` to a [glob pattern](http://zsh.sourceforge.net/Doc/Release/Expansion.html#Glob-Operators) to prevent offering completion suggestions when the buffer matches that pattern. For example, set it to `"git *"` to disable completion suggestions for git subcommands.
If you have a problem, please search through [the list of issues on GitHub](https://github.com/zsh-users/zsh-autosuggestions/issues?q=) to see if someone else has already reported it.
Before reporting an issue, please try temporarily disabling sections of your configuration and other plugins that may be conflicting with this plugin to isolate the problem.
- The smallest, simplest `.zshrc` configuration that will reproduce the problem. See [this comment](https://github.com/zsh-users/zsh-autosuggestions/issues/102#issuecomment-180944764) for a good example of what this means.
Tests are written in ruby using the [`rspec`](http://rspec.info/) framework. They use [`tmux`](https://tmux.github.io/) to drive a pseudoterminal, sending simulated keystrokes and making assertions on the terminal content.
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`).
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 pull ericfreese/zsh-autosuggestions-test
```
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 -e TEST_ZSH_BIN=zsh-<version> -v $PWD:/zsh-autosuggestions zsh-autosuggestions-test make test