Two optional tests fails (perhaps this is already known):
$ ./sage --version
SageMath Version 6.10.rc1, Release Date: 2015-12-13
sage -t src/sage/groups/generic.py
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File "src/sage/groups/generic.py", line 1388, in sage.groups.generic.structure_description
Failed example:
G.structure_description() # optional - database_gap
Expected:
'C7'
Got:
'"C7"'
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File "src/sage/groups/generic.py", line 1393, in sage.groups.generic.structure_description
Failed example:
groups.matrix.GL(4,2).structure_description() # optional - database_gap
Expected:
'A8'
Got:
'"A8"'
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1 item had failures:
2 of 14 in sage.groups.generic.structure_description
[215 tests, 2 failures, 7.47 s]