Merge lp:~oddbloke/vmbuilder/mfdiff into lp:~ubuntu-on-ec2/vmbuilder/mfdiff

[Dan Watkins]

[Chris Glass (tribaal)]

Nice!

TIL: operator.methodcaller.

+1

review: Approve

[Philip Roche (philroche)]

+1

review: Approve

[Philip Roche (philroche)]

I did approve this but I'm now a little confused after reading the docstring for operator.methodcaller.

"""
Return a callable object that calls the given method on its operand.
After f = methodcaller('name'), the call f(r) returns r.name().
After g = methodcaller('name', 'date', foo=1), the call g(r) returns
r.name('date', foo=1).
"""

When calling viewkeys do we need to use six as viewkeys' operand?

=== modified file 'mfdiff'
--- mfdiff	2017-06-27 18:56:52 +0000
+++ mfdiff	2017-08-15 13:28:06 +0000
@@ -39,7 +39,18 @@
 import apt
 import requests
 from debian.changelog import Changelog
-from six import iteritems, viewkeys
+from six import PY3, iteritems
+
+try:
+    from six import viewkeys
+except ImportError:
+    # The version of six in trusty doesn't have viewkeys, so pull in the six
+    # code from a more recent version if we can't get it directly from six.
+    import operator
+    if PY3:
+        viewkeys = operator.methodcaller("keys")
+    else:
+        viewkeys = operator.methodcaller("viewkeys")
 
 try:
     from apt import VersionCompare as version_compare