import-checker: ensure cffi is always a system module
I've had reports that this is not always happening, so whitelist it
the way we whitelist other problem cases.
--- a/contrib/import-checker.py Thu Jun 23 18:21:25 2016 +0100
+++ b/contrib/import-checker.py Thu Jun 23 20:45:37 2016 -0400
@@ -186,6 +186,9 @@
>>> 'cStringIO' in mods
True
+
+ >>> 'cffi' in mods
+ True
"""
for m in sys.builtin_module_names:
yield m
@@ -198,6 +201,8 @@
yield m
for m in 'cPickle', 'datetime': # in Python (not C) on PyPy
yield m
+ for m in ['cffi']:
+ yield m
stdlib_prefixes = set([sys.prefix, sys.exec_prefix])
# We need to supplement the list of prefixes for the search to work
# when run from within a virtualenv.