envy

Envy

Envy is a shell helper program that automatically sets environment variables when you enter certain directories, and properly undoes its actions when you leave them.

It executes very fast (typically in about 10 ms) every time when your shell (bash, zsh or fish) is about to print its prompt. Unlike many tools written in Python or shell script, it will not make your shell feel sluggish, and upgrading Python will not break your shell.

Envy can be used to replace the shell integration part of tools like pyenv, nvm and asdf. It sets environment variables with the root of the current git repository and the active branch without executing git, which you can use to customize your shell prompt. It also loads custom environment variables from local .envy files.

Screenshot

Installation

macOS

Mac users can use Homebrew to quickly install the binary release (no compilation required):

$ brew install wojas/tap/envy

Binary releases

Binary packages can be found on the Github Releases page.

Install from source

To install from source, you need to have Go 1.10 installed and GOPATH set. Then run:

$ go install github.com/wojas/envy

Configuring your shell

In order to use envy, simply add the following to your ~/.bashrc or ~/.zshrc:

function precmd { eval $(envy session) }

Fish users can create a ~/.config/fish/conf.d/envy.fish file with the following contents:

function _envy_fish_prompt_event --on-event fish_prompt
    eval (envy -fish session)
end

Usage

Envy will automatically:

• Add any bin, .venv/bin (Python) and node_modules/.bin directory in your current working directory, or in one of the directories higher up, to your PATH.
• Set a path as the GOPATH if it contains a bin, pkg and src directory.
• Set all environment variables defined in .envy files.
• Set _ENVY_GITROOT and _ENVY_BRANCH when you enter a git repository.
• Correctly undo all relevant changes when you leave the directories.

For safety, envy currently only performs these actions for directories nested under your home directory. This will be made configurable in a future release.

The .envy files have the same format as .env files, but some environment variables are handled specially:

• ENVY_EXTEND_PATH extends you PATH with the given : separated paths.
• ENVY_GOROOT sets the path as your GOROOT and adds $GOROOT/bin to your PATH.

Example .envy file:

FOO=bar
# This sets GOROOT and adds the bin directory to PATH
ENVY_GOROOT=~/sdk/go1.10
# Note that you can specify these relative to your current dir
ENVY_EXTEND_PATH=/some/path/bin:./other/path/bin

Values can be quoted, but this is not required.

FAQ

Q: Does envy automatically load .env files?

Originally it did, but I found that this has too many undesired side effects:

• You can no longer easily override a variable in your shell session.
• Tools like Docker Compose then treat file paths like COMPOSE_FILE relative to your current directory, instead of relative to the directory that contains your docker-compose.yml.

If you really want to load a .env file, you can symlink it to .envy.