id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	size
67	Fix negative indexing in groups/diffs.py	adehnert		"We're occasionally getting this traceback:
{{{
Traceback (most recent call last):
  File ""./groups/diffs.py"", line 248, in <module>
    generate_diffs()
  File ""./groups/diffs.py"", line 243, in generate_diffs
    diff_objects(objs, since=recent, callbacks=callbacks)
  File ""./groups/diffs.py"", line 213, in diff_objects
    after = after_versions[-1]
  File ""/usr/lib/python2.7/site-packages/django/db/models/query.py"", line 157, in __getitem__
    ""Negative indexing is not supported.""
AssertionError: Negative indexing is not supported.
}}}

(For example, https://diswww.mit.edu/menelaus/asa-db/736.)

We should fix this, and possibly make it robust enough to continue running even when something like that gets run into."	defect	closed	normal	Near Release	Core		fixed			medium