#15156: Pickling with __reduce__() loops creates invalid pickles
-------------------------------------+-------------------------------------
Reporter: vbraun | Owner:
Type: defect | Status: needs_info
Priority: major | Milestone: sage-6.3
Component: misc | Resolution:
Keywords: | Merged in:
Authors: SimonKing, | Reviewers:
jkeitel, novoselt, nbruin | Work issues:
Report Upstream: N/A | Commit:
Branch: | 9e449c3269e35238397a684d3262651b6bd74d51
u/saraedum/ticket/15156 | Stopgaps:
Dependencies: |
-------------------------------------+-------------------------------------
Changes (by saraedum):
* commit: => 9e449c3269e35238397a684d3262651b6bd74d51
Comment:
I found this useful to find out which object causes the cyclic reference.
It traverses the graph which `__reduce__` creates and looks for cycles. It
is certainly not complete, so I do not want to include it into sage like
this.
{{{
from collections import defaultdict
graph = {}
decode_graph = {}
queue = [o]
while queue:
o = queue.pop()
if id(o) in graph:
continue
decode_graph[id(o)] = o
if isinstance(o, (list, tuple)):
reduction = (None, list(o))
elif isinstance(o, dict):
reduction = (None, list(o.keys()) + list(o.values()))
elif isinstance(o, (str, int, float)):
reduction = (None, [])
else:
try:
reduction = o.__reduce_ex__(2)
except TypeError:
reduction = (None, [])
args = reduction[1]
graph[id(o)] = [id(a) for a in args]
queue.extend(args)
if len(reduction) >= 3:
queue.append(reduction[2])
if len(reduction) >= 4:
queue.append(reduction[3])
if len(reduction) >= 5:
queue.append(reduction[4])
from sage.graphs.digraph import DiGraph
graph = DiGraph(graph)
for cycle in graph.all_simple_cycles():
print [decode_graph[i] for i in cycle]
}}}
----
New commits:
||[http://git.sagemath.org/sage.git/commit/?id=98d17b4eb321ba74c85956131aa153120e208c5d
98d17b4]||{{{Check for invalid pickles in _test_pickling()}}}||
||[http://git.sagemath.org/sage.git/commit/?id=9e449c3269e35238397a684d3262651b6bd74d51
9e449c3]||{{{Fix a circular reference in
PermutationGroupElement.__reduce__()}}}||
--
Ticket URL: <http://trac.sagemath.org/ticket/15156#comment:10>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
