Fix Scheduler._choose_pkg() to perform uninstallation actions (due to

blockers) in the correct order when building in parallel.

svn path=/main/trunk/; revision=10996

diff --git a/pym/_emerge/__init__.py b/pym/_emerge/__init__.py
index cd43593de064e3dab2080a356765feae7ea63202..1c652e69181d97021a438ca10763d91793585f8a 100644 (file)
--- a/pym/_emerge/__init__.py
+++ b/pym/_emerge/__init__.py
@@ -7710,8 +7710,31 @@ class Scheduler(object):
                        return
 
                self._digraph = digraph
+               self._reverse_uninstall_edges()
                self._prune_digraph()
 
+       def _reverse_uninstall_edges(self):
+               """
+               The uninstall is performed only after blocking packages have been
+               merged on top of it (similar to how a normal upgrade is performed
+               by first merging the new version on top of the onld version). This
+               is implemented by reversing the the parent -> uninstall edges in
+               the graph.
+               """
+
+               graph = self._digraph
+
+               for node in self._mergelist:
+                       if not isinstance(node, Package) or \
+                               node.operation != "uninstall":
+                               continue
+
+                       parent_nodes = graph.parent_nodes(node)
+                       graph.remove(node)
+                       for blocked_pkg in parent_nodes:
+                               graph.add(blocked_pkg, node,
+                                       priority=BlockerDepPriority.instance)
+
        def _prune_digraph(self):
                """
                Prune any root nodes that are irrelevant.
@@ -8104,18 +8127,15 @@ class Scheduler(object):
 
        def _choose_pkg(self):
                """
-               TODO: fix order for uninstall operations
+               Choose a task that has all it's dependencies satisfied.
                """
-               if self._max_jobs < 2 or self._jobs == 0 or \
-                       self._pkg_queue[0].operation == "uninstall":
+               if self._max_jobs < 2 or self._jobs == 0:
                        return self._pkg_queue.pop(0)
 
                self._prune_digraph()
 
                chosen_pkg = None
                for pkg in self._pkg_queue:
-                       if pkg.operation == "uninstall":
-                               continue
                        if not self._dependent_on_scheduled_merges(pkg):
                                chosen_pkg = pkg
                                break