SVN Paths Are Case Sensitive

Over the last couple of days I've been busy re-installing the computer that runs my SVN repository (it runs other things as well but that isn't so important). It's a Windows machine and it had finally reached the point where the only solution to the BSODs it kept suffering was a full re-install.

I've never been particularly good at making regular backups of things and while I've suffered a fair amount of hardware failures over the years I've never really lost anything important. In fact the SVN repository itself has saved me from a disk crash recently. So at the same time as the re-install I thought I should setup a proper back schedule and organize my data a little more carefully.

So I now have two disks in the machine that are not used for day-to-day stuff. One drive holds the live copy of the SVN repository (as well as the Hudson home dir, Tomcat webapps and associated MySQL data). The other drive holds backup copies of everything.

This re-organization meant that local path access to the SVN repository changed (the external svn:// URL stayed the same), which meant I had to update the Hudson configurations (which use local file access for performance) to use the new paths.

So I went through each of the 12 jobs in Hudson and changed the paths accordingly. I checked a few of the projects and they built without any problems so I assumed that was job done. Then this morning I noticed that all 12 jobs were being built every 10 minutes as polling SVN always reported that the workspace didn't contain a checkout of the correct folder. The path it was showing was correct so at first glance nothing appeared wrong. After messing around at the command line for a bit I eventually figured out the problem.

Basically I'd changed from URLs starting file:///z:/SVN to URLs starting file:///L:/SVN. For some reason I'd typed in the drive letter as a capital (the way Windows displays it) rather than in lower case. It turns out that while SVN is happy to do a checkout from the capital letter version it stores the URL in the checked out copy using a lowercase drive letter, and hence on future updates the two don't match. Fixing the jobs to access URLs starting file:///l:/SVN fixed the problem.

Bizarrely Hudson didn't complain about the problem so the builds all succeeded it's just that there was an awful lot of wasted CPU time over the last day or so!