Partial rendering results in a blank page?

Neil Middleton wrote:

I'm stuck with a bug at the moment which is puzzling me. I have a
layout containing some HTML and a partial (for the navigation) - there
is nothing else there other than the yield.

1. If the nav is included as a partial I get nothing returned to the
browser at all (blank page) but everything else appears normal
2. If I remove the partial the page works fine
3. If I put the nav code directly in the template it works fine
4. if I replace the nav code in the partial with a simple string, I get
a blank page again.

Does anyone have any ideas as to what the problem could be, or know how
I might debug it?

Found the issue, the partial was in the layouts folder, instead of the
relevant controller views folder.

However, Rails was throwing a ActionView::MissingTemplate Exception
which was only visible via the debugger which is probably a bug.