Virtualenv for bash

Question

I really like virtualenv when working with python code and am wondering if there existed some tool which could emulate some of it when working in bash.

What I want is some cleanly reverseble way of setting environment variables by loading/unloading configurations.

I know about a lot of tools which do some magic when entering some directory, but I guess I wouldn't want to start from something like that.

Answer 1

not sure if it's what you're looking for but I have this on my rc files:

mklab() {
    # creates small test environments for scripting
    local d=$(mktemp -d) && cd "$d" || return 1
    clear; bash --login --noprofile --norc
    cd - && rm -r "$d"
}; export -f mklab

it puts you in a temp directory with a clean shell to make tests and removes it afterwards.

virtualenv is a bad example for bash because here you don't "install" libraries, if you're looking for a way to easily switch between bash versions you should mention that on the question.

Answer 2

A naive attempt:

to load env:

shvirtualenv() ( source "$1"; VIRTUALENV="$1" bash; )

On exit one should save variables (or not if undesirable):

shvirtualenv_exit() {
    # one could ask here whether to save the env:
    declare -x > $VIRTUALENV
}

trap EXIT shvirtualenv_exit

CONS:

• It does not handle inheritance well: if you want to source another env on save it will save all and further changes in parent env are not reflected.
• Another problem is with multiple sessions (just open another terminal) - now you will end up with conflicts

TODO:

• I would love to see separate history for the env.
• per-project bashrc