How do I change the default virtualenv prompt?

If you are working on a custom PS1 (as I when found out this issue), I recommend you to disable prompt change, use export VIRTUAL_ENV_DISABLE_PROMPT=1 (see virtualenv docs), and make your own virtualenv prompt in order to add to your PS1.

See this snippet that I've used:

function virtualenv_info(){    # Get Virtual Env    if [[ -n "$VIRTUAL_ENV" ]]; then        # Strip out the path and just leave the env name        venv="${VIRTUAL_ENV##*/}"    else        # In case you don't have one activated        venv=''    fi    [[ -n "$venv" ]] && echo "(venv:$venv) "}# disable the default virtualenv prompt changeexport VIRTUAL_ENV_DISABLE_PROMPT=1VENV="\$(virtualenv_info)";# the '...' are for irrelevant info here.export PS1="... ${VENV} ..."

I think the following is the simplest solution:

Add to ~/.virtualenvs/postactivate the following:

PS1="\[\e[1;33;45m\] (`basename \"$VIRTUAL_ENV\"`) \[\e[0m\]$_OLD_VIRTUAL_PS1"

Taken from: http://wiki.hackzine.org/development/python/virtualenv.html

By default, when you switch into a virtualenv with the command "workon < name_of_env >", virtualenvwrapper prepends a string along the lines of "(< name_of_env >) " to your command prompt. The problem is that I set my Bash prompt with the lines:

PROMPT_COLOR1='0;36m'PROMPT_COLOR2='1;34m'PS1='\n\[\033[$PROMPT_COLOR1\](\t)\[\033[$PROMPT_COLOR2\] \u @ \w \n\[\033[$PROMPT_COLOR1\]$ \[\033[0;39m\]'

Which yields a command prompt along the lines of:

< old_line >(19:11:05) kevin @ ~/research $ 

Switching into a new virtual environment with "workon < name_of_env >" turned the command prompt to something like:

< old_line >(< name_of_env >)(19:11:05) kevin @ ~/research $ 

Which was more cluttered than I wanted and the wrong color to boot. I was hoping for something like:

< old_line >(< name_of_env >) (19:11:05) kevin @ ~/research $ 

Ian Bicking has previously pointed out that virtualenvwrapper's hooks were the solution but I figured I'd post my actual code to maybe save someone else a minute down the line.

I simply edited the file $WORKON_HOME/postactivate to include these lines:

# color virtualenv name properly and put it after the \n if there is one at the start of the promptif [ ${_OLD_VIRTUAL_PS1:0:2} == '\n' ]; then    PS1="\n\[\033[$PROMPT_COLOR1\](`basename \"$VIRTUAL_ENV\"`) ${_OLD_VIRTUAL_PS1:2:${#_OLD_VIRTUAL_PS1}}"else    PS1="\[\033[$PROMPT_COLOR1\](`basename \"$VIRTUAL_ENV\"`) $_OLD_VIRTUAL_PS1 "fi

and voila! The color and location are correct and it even works when you switch directly from one virtual environment to another (which I hadn't expected).