How do I change the default virtualenv prompt?
bash, command-prompt, python, virtualenv, virtualenvwrapper
Solution
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 prompt
if [ ${_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).
Problem
How do you change the default Virtualenvwrapper prompt? By default, working on a particular virtual environment with a command like `workon <_name_of_env_>` prepends the name of the virtualenv to your prompt. This may work poorly if you're not using a default command prompt.