CC'ing two people who are listed in the copyright lines.

Patch #1: factor out code the 'check' phase of tryton modules
  in a procedure, as they are almost all exactly the same except
  for the module name.

  This one does not cause any change in derivation (no rebuilds).

Patch #2: Use 'inputs' argument to the 'check' phase instead of
  %build-inputs.

  I tried building some tryton modules and it seemed to work well.
  No failures, but I didn't try all.

Patch #3: Respect tests?, allow --without-tests.

  I tested building a single tryton module.

Greetings,
Maxime.