[Sqlalchemy-tickets] [sqlalchemy] #2794: CircularDependencyError with jython because WeakSequence doesn't preserve order

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#2794: CircularDependencyError with jython because WeakSequence doesn't preserve
order
--------------------+-----------------------------------------
 Reporter:  sayap   |           Owner:  zzzeek
     Type:  defect  |          Status:  new
 Priority:  medium  |       Milestone:
Component:  utils   |        Severity:  no triage selected yet
 Keywords:          |  Progress State:  awaiting triage
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 I am toying with Jython, and the same app that works fine with CPython
 somehow throws a `CircularDependencyError` when trying to insert an
 instance of a mapped class that participates in a joined table
 inheritance.

 I trace down the culprit to be `WeakSequence.__iter__()`, which doesn't
 preserve the insertion order.

 Changing the line from:
 {{{
 # 0.8
 return self._storage.itervalues()
 }}}
 or:
 {{{
 # 0.9
 return iter(self._storage.values())
 }}}
 to:
 {{{
 for idx in sorted(self._storage):
     yield self._storage[idx]
 }}}
 make things work again on Jython.

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Ticket URL: <http://www.sqlalchemy.org/trac/ticket/2794>
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