Switching an SVN directory to and from an ‘externals’ definition

There seems to be quite a few posts out there about how to replace Subversion externals definitions with local directories, but not so much for going the other way. I’m not sure why; it seems to me more likely that one would start off with some small module as part of a bigger repository, and then at a later date want to move it out to live on its own. I don’t really know what I’m on about, though.

The point being, that I’m working with a branch of a project that is having a few of its directories — its current, local, ‘normal’ directories — replaced by externals definitions. That’s all fine and good, but I keep having to switch to trunk and back again, and there’s the crux: the directories that are getting turned into externals do not like being switched.

Running the usual svn sw http://svn.example.com/repo/branches/v2 from the top level of a trunk checkout gives the following error:

Fetching external item into 'lib/foo':
svn: warning: W155037: Previous operation has not finished; run 'cleanup' if it was interrupted

Running svn cleanup complains with:

svn: E155010: The node '/path-to-repo/lib/foo/file.txt' is not installable

And not even status has anything useful to say (throwing instead the same error as above).

A solution (and yes, this post is probably a bit long-winded for such a short snippet of advice; I can only say that I felt like writing this down this morning because four weeks ago I figured it out but forgot and I suspect that four weeks hence I’ll have forgotten again, and this morning is one of those moments of verbosity; blame Travels with Charley, which I was reading over breakfast this morning), and it’s probably not the ‘proper’ solution because I’m no Subversion hacker and do rather treat it as magic, but the solution that I use is (and I’d better put it on it’s own line, because no one’s likely to have read to the end of this paragraph)…

Solution:

Delete the offending directory (as in, rm -r lib/foo or what have you), and update again.

That’s all.