McFly - fly through your shell history

McFly replaces your default ctrl-r shell history search with an intelligent search engine that takes into account your working directory and the context of recently executed commands. McFly's suggestions are prioritized in real time with a small neural network.

TL;DR: an upgraded ctrl-r where history results make sense for what you're working on right now.

Features

• Rebinds ctrl-r to bring up a full-screen reverse history search prioritized with a small neural network.
• Augments your shell history to track command exit status, timestamp, and execution directory in a SQLite database.
• Maintains your normal shell history file as well so that you can stop using McFly whenever you want.
• Unicode support throughout.
• Includes a simple action to scrub any history item from the McFly database and your shell history files.
• Designed to be extensible for other shells in the future.
• Written in Rust, so it's fast and safe.
• You can type % to match any number of characters when searching.

Prioritization

The key feature of McFly is smart command prioritization powered by a small neural network that runs in real time. The goal is for the command you want to run to always be one of the top suggestions.

When suggesting a command, McFly takes into consideration:

• The directory where you ran the command. You're likely to run that command in the same directory in the future.
• What commands you typed before the command (e.g., the command's execution context).
• How often you run the command.
• When you last ran the command.
• If you've selected the command in McFly before.
• The command's historical exit status. You probably don't want to run old failed commands.

Installation

Install with Homebrew (on OS X or Linux)

1. Install the tap: bash brew tap cantino/mcfly
2. Install mcfly: bash brew install mcfly

3. Add the following to the end of your ~/.bashrc, ~/.zshrc, or ~/.config/fish/config.fish file:

   Bash: bash eval "$(mcfly init bash)"

   Zsh: bash eval "$(mcfly init zsh)"

   Fish: bash mcfly init fish | source

4. Run . ~/.bashrc / . ~/.zshrc / source ~/.config/fish/config.fish or restart your terminal emulator.

Uninstalling with Homebrew

1. Remove mcfly: bash brew uninstall mcfly
2. Remove the tap: bash brew untap cantino/mcfly
3. Remove the lines you added to ~/.bashrc / ~/.zshrc / ~/.config/fish/config.fish.

Install with MacPorts (on OS X)

1. Update the ports tree bash sudo port selfupdate
2. Install mcfly: bash sudo port install mcfly

3. Add the following to the end of your ~/.bashrc, ~/.zshrc, or ~/.config/fish/config.fish file, as appropriate:

   Bash: bash eval "$(mcfly init bash)"

   Zsh: bash eval "$(mcfly init zsh)"

   Fish: bash mcfly init fish | source

4. Run . ~/.bashrc / . ~/.zshrc / source ~/.config/fish/config.fish or restart your terminal emulator.

Uninstalling with MacPorts

1. Remove mcfly: bash sudo port uninstall mcfly
2. Remove the lines you added to ~/.bashrc / ~/.zshrc / ~/.config/fish/config.fish.

Installing using our install script

1. curl -LSfs https://raw.githubusercontent.com/cantino/mcfly/master/ci/install.sh | sh -s -- --git cantino/mcfly

2. Add the following to the end of your ~/.bashrc, ~/.zshrc, or ~/.config/fish/config.fish file, respectively:

   Bash:

   bash eval "$(mcfly init bash)"

   Zsh:

   bash eval "$(mcfly init zsh)"

   Fish:

   bash mcfly init fish | source

3. Run . ~/.bashrc / . ~/.zshrc / source ~/.config/fish/config.fish or restart your terminal emulator.

Installing manually from GitHub

1. Download the latest release from GitHub.
2. Install to a location in your $PATH. (For example, you could create a directory at ~/bin, copy mcfly to this location, and add export PATH="$PATH:$HOME/bin" to your .bashrc / .zshrc, or run set -Ua fish_user_paths "$HOME/bin" for fish.)

3. Add the following to the end of your ~/.bashrc, ~/.zshrc, or ~/.config/fish/config.fish file, respectively:

   Bash: bash eval "$(mcfly init bash)"

   Zsh: bash eval "$(mcfly init zsh)"

   Fish: bash mcfly init fish | source

4. Run . ~/.bashrc / . ~/.zshrc / source ~/.config/fish/config.fish or restart your terminal emulator.

Install manually from source

1. Install Rust 1.40 or later
2. Run git clone https://github.com/cantino/mcfly and cd mcfly
3. Run cargo install --path .
4. Ensure ~/.cargo/bin is in your $PATH.

5. Add the following to the end of your ~/.bashrc, ~/.zshrc, or ~/.config/fish/config.fish file, respectively:

   Bash: bash eval "$(mcfly init bash)"

   Zsh: bash eval "$(mcfly init zsh)"

   Fish: bash mcfly init fish | source

6. Run . ~/.bashrc / . ~/.zshrc / source ~/.config/fish/config.fish or restart your terminal emulator.

Install by Zinit

• Add below code to your zshrc.

  zsh zinit ice lucid wait"0a" from"gh-r" as"program" atload'eval "$(mcfly init zsh)"' zinit light cantino/mcfly

• It will download mcfly and install for you.
• $(mcfly init zsh) will be executed after prompt

iTerm2

To avoid McFly's UI messing up your scrollback history in iTerm2, make sure this option is unchecked:

Settings

A number of settings can be set via environment variables. To set a setting you should add the following snippets to your ~/.bashrc / ~/.zshrc / ~/.config/fish/config.fish.

Light Mode

To swap the color scheme for use in a light terminal, set the environment variable MCFLY_LIGHT.

bash / zsh: bash export MCFLY_LIGHT=TRUE

fish: bash set -gx MCFLY_LIGHT TRUE

Tip: on macOS you can use the following snippet for color scheme to be configured based on system-wide settings:

bash / zsh: bash if [[ "$(defaults read -g AppleInterfaceStyle 2&>/dev/null)" != "Dark" ]]; then export MCFLY_LIGHT=TRUE fi

VIM Key Scheme

By default Mcfly uses an emacs inspired key scheme. If you would like to switch to the vim inspired key scheme, set the environment variable MCFLY_KEY_SCHEME.

bash / zsh: bash export MCFLY_KEY_SCHEME=vim

fish: bash set -gx MCFLY_KEY_SCHEME vim

Fuzzy Searching

To enable fuzzy searching, set MCFLY_FUZZY to an integer. 0 is off; higher numbers weight toward shorter matches. Values in the 2-5 range get good results so far; try a few and report what works best for you!

bash / zsh: bash export MCFLY_FUZZY=2

fish: bash set -gx MCFLY_FUZZY 2

Results Count

To change the maximum number of results shown, set MCFLY_RESULTS (default: 10).

bash / zsh: bash export MCFLY_RESULTS=50

fish: bash set -gx MCFLY_RESULTS 50

Interface view

To change interface view, set MCFLY_INTERFACE_VIEW (default: TOP). Available options: TOP and BOTTOM

bash / zsh: bash export MCFLY_INTERFACE_VIEW=BOTTOM

fish: bash set -gx MCFLY_INTERFACE_VIEW BOTTOM

Disable menu interface

To disable the menu interface, set the environment variable MCFLY_DISABLE_MENU.

bash / zsh: bash export MCFLY_DISABLE_MENU=TRUE

fish: bash set -gx MCFLY_DISABLE_MENU TRUE

Results sorting

To change the sorting of results shown, set MCFLY_RESULTS_SORT (default: RANK). Possible values RANK and LAST_RUN

bash / zsh: bash export MCFLY_RESULTS_SORT=LAST_RUN

fish: bash set -gx MCFLY_RESULTS_SORT LAST_RUN

Database Location

McFly stores its SQLite database in the standard location for the OS. On OS X, this is in ~/Library/Application Support/McFly and on Linux it is in $XDG_DATA_DIR/mcfly/history.db (default would be ~/.local/share/mcfly/history.db). For legacy support, if ~/.mcfly/ exists, it is used instead.

Slow startup

If you have a very large history database and you notice that McFly launches slowly, you can set MCFLY_HISTORY_LIMIT to something like 10000 to limit how many records are considered when searching. In this example, McFly would search only the latest 10,000 entries.

Possible Future Features

• Add a screencast to README.
• Learn common command options and autocomplete them in the suggestion UI?
• Sort command line args when coming up with the template matching string.
• Possible prioritization improvements:
  • Cross validation & explicit training set selection.
  • Learn command embeddings

Development

Contributing

Contributions and bug fixes are encouraged! However, we may not merge PRs that increase complexity significantly beyond what is already required to maintain the project. If you're in doubt, feel free to open an issue and ask.

Running tests

cargo test

Releasing (notes for @cantino)

1. Edit Cargo.toml and bump the version.
2. Edit CHANGELOG.txt
3. Run cargo clippy and cargo fmt.
4. Recompile (cargo build).
5. git add -p
6. git ci -m 'Bumping to vx.x.x'
7. git tag vx.x.x
8. git push origin head --tags
9. Let the build finish.
10. Edit the new Release on Github.
11. Edit pkg/brew/mcfly.rb and update the version and SHAs. (shasum -a 256 ...)
12. Edit ../homebrew-mcfly/pkg/brew/mcfly.rb too.
    1. cp pkg/brew/mcfly.rb ../homebrew-mcfly/pkg/brew/mcfly.rb
    2. Compare with diff ../homebrew-mcfly/pkg/brew/mcfly.rb ../mcfly/pkg/brew/mcfly.rb ; diff ../homebrew-mcfly/HomebrewFormula/mcfly.rb ../mcfly/HomebrewFormula/mcfly.rb
13. git add -p && git ci -m 'Update homebrew' && git push
14. cd ../homebrew-mcfly && git add -p && git ci -m 'Update homebrew' && git push && cd ../mcfly
15. cargo publish