Subversion and the bash prompt

I recently found this entry that shows how you can update your PS1 value to display certain information about your git workspace.  I don't get to use git too much right now, but I use subversion a lot and wondered what there was for that.  I didn't find anything in the bash-completion entries for svn (though I admittedly didn't look too hard) so I whipped up my own solution late last night. One slight disclaimer before seeing the script:  it was late when i wrote this.  There doesn't appear to be any noticeable performance hits other than the initial run of this script but I make no guarantees.  I'm sure it could be optimized but it's snappy enough and might prove to be mildly useful.  It was interesting enough at midnight at least.  :)  Anyway, the code!

#! /bin/sh
extract() {
	TEXT=$( svn info | grep "$1" )
	echo ${TEXT##$1}
}

if [ -e .svn ]
then
	URL=`extract "URL: "`
	REPROOT=`extract "Repository Root: "`

	echo "\n\033[01;33m[svn: ${URL##$REPROOT}] \033[01;34m"
fi

This can be displayed in your command prompt by setting your PS1 variable like this:

export PS1='\[\033[01;32m\]\u@\h\[\033[01;34m\] \w $(svn_ps1)\$\[\033[00m\] '

The single quotes are important there to prevent immediate execution of the script. If you use double quotes, it will be evaluated immediately and your prompt won't update as you navigate around. You only need to save the first script as svn_ps1 somewhere on your PATH or name it as you wish and update the PS1 variable accordingly. You can, of course, specify the full path in the PS1 var if you'd like. This setting will put the path within the current subversion repository in yellow text on a new line. If you're not in a subversion workspace, your prompt is unaffected. I had some code in there to strip off the relevant portions of the cwd from that display so you essentially only saw what branch or tag you were or if you were in trunk. With the script as it is, there's some redundancy between the subversion info display and the cwd shown, but I can live with that.

I switch between branches and even version control systems often enough that i'll probably expand on this to work for git/svn/hg/cvs accordingly. Next time I'm up late hacking.