# Thursday, July 16, 2015¶

Yesterday I started to worked on #340 (Reception clerk sees “Career” tab).

This problem was rather subtle and took me quite some hours of investigation, mainly using the tested document Reception clerk sees "Career" tab.

It was due to a bug in Lino. lino.modlib.extjs.ext_renderer.ExtRenderer.write_lino_js() used to run a method loosen_requirements in the following lines:

for e in lh.main.walk():
e.loosen_requirements(res)


This was needed because we said that for example an InsertFormPanel has initially the requirements of the actor who defines it. That actor may not be visible to the current user. But the panel may be used by other actors which are visible because they have less requirements. So there are panel for which we need to generate a JS code definition even though the actor who defines them is not available.

But the old approach modified the global element tree. This caused the described side effect. As long as this process didn’t run, everything was okay.

So I replaced it by a different approach: the individual elements no longer inherit the required_roles of their actor, and we have a new attribute _other_datasources on every lino.core.layouts.BaseLayout instance in order to decide whether the code is to be included in that profile’s lino*.js file or not.

Fixing this unveiled also a minor problem of plugin interdependency (lino.modlib.system needs lino.modlib.printing or so).