partials named "_next" crash render

To repro, create a partial called, "_next.html.erb", then try to render it.

You get something like the following:

Showing widget/profile_completeness/_next.html.erb where line #52 raised:

compile error
/[path_removed]/_next.html.erb:-3: syntax error, unexpected '=', expecting kEND
next = local_assigns[:next]
     ^

It should probably either not crash or at least raise an explanatory exception.