launchpad-reviewers team mailing list archive

[Gavin Panella <gavin.panella@xxxxxxxxxxxxx>]

Gavin Panella has proposed merging lp:~allenap/launchpad/dsd-base-view-dont-modify-globals-bug-809985 into lp:launchpad with lp:~allenap/launchpad/selected-differences-vocab-bug-817408 as a prerequisite.

Requested reviews:
  Launchpad code reviewers (launchpad-reviewers)
Related bugs:
  Bug #809985 in Launchpad itself: "DistroSeriesDifferenceBaseView modifies shared objects"
  https://bugs.launchpad.net/launchpad/+bug/809985

For more details, see:
https://code.launchpad.net/~allenap/launchpad/dsd-base-view-dont-modify-globals-bug-809985/+merge/70076

Jump through hoops to avoid updating a global in a view, which I hope we agree would be a bad thing :)
-- 
https://code.launchpad.net/~allenap/launchpad/dsd-base-view-dont-modify-globals-bug-809985/+merge/70076
Your team Launchpad code reviewers is requested to review the proposed merge of lp:~allenap/launchpad/dsd-base-view-dont-modify-globals-bug-809985 into lp:launchpad.

=== modified file 'lib/lp/registry/browser/distroseries.py'
--- lib/lp/registry/browser/distroseries.py	2011-08-01 20:31:33 +0000
+++ lib/lp/registry/browser/distroseries.py	2011-08-01 20:31:35 +0000
@@ -828,9 +828,18 @@
         super(DistroSeriesDifferenceBaseView, self).initialize()
 
     def initialize_sync_label(self, label):
-        # XXX: GavinPanella 2011-07-13 bug=809985: Good thing the app servers
-        # are running single threaded...
-        self.__class__.actions.byname['actions.sync'].label = label
+        # Owing to the design of Action/Actions in zope.formlib.form - actions
+        # is actually a descriptor that copies itself and its actions when
+        # accessed - this has the effect of making a shallow copy of the sync
+        # action which we can modify.
+        actions = self.actions
+        sync_action = next(
+            action for action in actions if action.name == "sync")
+        sync_action.label = label
+        # Mask the actions descriptor with an instance variable.
+        self.actions = actions.__class__(
+            *((sync_action if action.name == "sync" else action)
+              for action in actions))
 
     @property
     def label(self):