Ensure that WorkingSet.resolve() (and therefore require() as well)

returns a list of the relevant distributions, even if they are found in
the working set rather than the environment.  This fixes some problems
in the 0.6a3 release.

--HG--
branch : setuptools
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/trunk/setuptools%4041256

pkg_resources.py

@@ -463,7 +463,7 @@ class WorkingSet(object):
 
         requirements = list(requirements)[::-1]  # set up the stack
         processed = {}  # set of processed requirements
-        best = dict([(d.key,d) for d in self])  # key -> dist
+        best = {}  # key -> dist
         to_activate = []
 
         while requirements:
@@ -471,20 +471,20 @@ class WorkingSet(object):
             if req in processed:
                 # Ignore cyclic or redundant dependencies
                 continue
-
             dist = best.get(req.key)
             if dist is None:
                 # Find the best distribution and add it to the map
-                if env is None:
-                    env = Environment(self.entries)
-                dist = best[req.key] = env.best_match(req, self, installer)
+                dist = self.by_key.get(req.key)
                 if dist is None:
-                    raise DistributionNotFound(req)  # XXX put more info here
+                    if env is None:
+                        env = Environment(self.entries)
+                    dist = best[req.key] = env.best_match(req, self, installer)
+                    if dist is None:
+                        raise DistributionNotFound(req)  # XXX put more info here
                 to_activate.append(dist)
             elif dist not in req:
                 # Oops, the "best" so far conflicts with a dependency
                 raise VersionConflict(dist,req) # XXX put more info here
-
             requirements.extend(dist.requires(req.extras)[::-1])
             processed[req] = True
 

pkg_resources.txt

@@ -1488,6 +1488,9 @@ File/Path Utilities
 Release Notes/Change History
 ----------------------------
 
+0.6a4
+ * Fix a bug in ``WorkingSet.resolve()`` that was introduced in 0.6a3.
+
 0.6a3
  * Added ``safe_extra()`` parsing utility routine, and use it for Requirement,
    EntryPoint, and Distribution objects' extras handling.

setuptools/tests/test_resources.py

@@ -123,7 +123,6 @@ class DistroTests(TestCase):
 
     def testResolve(self):
         ad = Environment([]); ws = WorkingSet([])
-
         # Resolving no requirements -> nothing to install
         self.assertEqual( list(ws.resolve([],ad)), [] )
 
@@ -131,7 +130,6 @@ class DistroTests(TestCase):
         self.assertRaises(
             DistributionNotFound, ws.resolve, parse_requirements("Foo"), ad
         )
-
         Foo = Distribution.from_filename(
             "/foo_dir/Foo-1.2.egg",
             metadata=Metadata(('depends.txt', "[bar]\nBaz>=2.0"))
@@ -139,10 +137,12 @@ class DistroTests(TestCase):
         ad.add(Foo)
 
         # Request thing(s) that are available -> list to activate
-        self.assertEqual(
-            list(ws.resolve(parse_requirements("Foo"), ad)), [Foo]
-        )
-
+        for i in range(3):
+            targets = list(ws.resolve(parse_requirements("Foo"), ad))
+            self.assertEqual(targets, [Foo])
+            map(ws.add,targets)
+        ws = WorkingSet([]) # reset
+        
         # Request an extra that causes an unresolved dependency for "Baz"
         self.assertRaises(
             DistributionNotFound, ws.resolve,parse_requirements("Foo[bar]"), ad