Endless loop with Acquisition and ILocation in Products.Five.component findSite

[gweis]

Prodcuts.Five.component findSite using the ILocation API or if not available the Acquisition chain to find a parent object. If an object Acquisition wrapped object implements the ILocation API the parent retrieved from obj.__parent__ is aq-wrapped in the context of obj which leads to an endless loop in finding an ISite.

The attached patches contain a doc-test to demonstrate the behaviour and a suggested fix. The fix just checks if the object is aq-wrapped before accessing the __parent__ attribute. This basically means, Acquisition is given preference to ILocation.

The patch against current Zope 2.11 development branch, and most likely applies to 2.10 too. I am not sure about 2.12 because there have been some changes to the Acquisition module.

cheers

Gerhard

[Hanno Schlichting (hannosch)]

In Zope 2.12 Acquisition has been made aware of __parent__pointers and the code ling in findSite only uses aq_parent, which does the correct thing internally.