collectstatic crashed when:
* a hashing static file storage backend was used
* a static file referenced another static file located directly in
STATIC_ROOT (not a subdirectory) with an absolute URL (which must
start with STATIC_URL, which cannot be empty)
It seems to me that the current code reimplements relative path joining
and doesn't handle edge cases correctly. I suspect it assumes that
STATIC_URL is of the form r'/[^/]+/'.
Throwing out that code in favor of the posixpath module makes the logic
easier to follow. Handling absolute paths correctly also becomes easier.
A @font-face declaration may contain a fragment that looks like a relative path,
e.g. @font-face { src: url('../fonts/font.svg#../path/like/fragment'); }
In this case, an incorrect path was passed to the storage backend, which raised
an error that caused collectstatic to crash.
This requires that each test never alters files in static directories
collected by other tests. The alternative is to add a temporary
directory to STATICFILES_DIRS or a new app to INSTALLED_APPS.
