[merge] trivial: make assertSubset use sets

[Martin Pool]

=== modified file 'bzrlib/tests/__init__.py'
--- bzrlib/tests/__init__.py    2007-08-15 03:01:38 +0000
+++ bzrlib/tests/__init__.py    2007-08-15 03:42:22 +0000
@@ -900,12 +900,9 @@

     def assertSubset(self, sublist, superlist):
         """Assert that every entry in sublist is present in superlist."""
-        missing = []
-        for entry in sublist:
-            if entry not in superlist:
-                missing.append(entry)
+        missing = set(sublist) - set(superlist)
         if len(missing) > 0:
-            raise AssertionError("value(s) %r not present in container %r" %
+            raise AssertionError("value(s) %r not present in container %r" %
                                  (missing, superlist))

     def assertListRaises(self, excClass, func, *args, **kwargs):

This cuts a few seconds off the runtime of the selftest --list-only
tests, and probably also helps others.

-- 
Martin