Introspection is failing on polynomial rings:

sage: R.<x> = QQ[] 
sage: R.su<tab> 
R.sum                               R.summation 
R.summation_from_element_class_add 
sage: R.sum? 
Object `R.sum` not found. 
sage: R.sum() 
--------------------------------------------------------------------------- 
AttributeError                            Traceback (most recent call last) 

This is because polynomial rings do not yet set their category properly:

sage: QQ[x]._test_category()
------------------------------------------------------------
Traceback (most recent call last):
...
AssertionError: category of self improperly initialized

See http://groups.google.com/group/sage-devel/browse_thread/thread/4780192a11a8b591 for more discussion.

Many other rings are not properly initialised as well. The aim of this ticket is to change that.

Apply attachment: 9138_flat.patch (rebased on top of #9958, but will still apply with fuzz 2 otherwise).

See #11900 for a follow-up fixing some speed regressions.

Depends on #11900

Dependencies: To be merged with #11900

CC: @sagetrac-sage-combinat @robertwb

Component: categories

Keywords: introspection, categories for rings

Author: Simon King

Reviewer: Volker Braun

Merged: sage-5.0.beta0

Issue created by migration from https://trac.sagemath.org/ticket/9138