fix readable forms in the case of a top-level ref-less group

fixes http://manage.dimagi.com/default.asp?124053

first commit fixes, second commit adds regression test
I put this assert here because nothing the user puts in should change this
fact. The assert that caught the error was also a good one—it exposed a way
in which user input *could* change that invariant, which this pr fixes.
On Jul 23, 2014 8:05 AM, "Cory Zue" <notifications@github.com> wrote:

> In corehq/apps/reports/formdetails/readable.py:
>
> > @@ -167,6 +171,14 @@ def path_relative_to_context(path, path_context):
> >          return path
> >
> >
> > +def absolute_path_from_context(path, path_context):
> > +    assert path_context.endswith('/')
>
> not knowing too much about how this works - are you at all worried this
> will get raised on other nonstandard forms? or was this assertion already
> implicit elsewhere in the code.
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/dimagi/commcare-hq/pull/3918/files#r15283765>.
>