get_dep_chain: prefer parents in merge list

This will fix bug #354747.

diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index 2257318d2f50f62a97fe145235ccc65eccf43781..1b76f5323e4d19a8e9ee64061206d6d8be2620d7 100644 (file)
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -2373,20 +2373,20 @@ class depgraph(object):
                        # When traversing to parents, prefer arguments over packages
                        # since arguments are root nodes. Never traverse the same
                        # package twice, in order to prevent an infinite loop.
+                       child = node
                        selected_parent = None
+                       parent_arg = None
+                       parent_merge = None
+
                        for parent in self._dynamic_config.digraph.parent_nodes(node):
                                if parent in traversed_nodes:
                                        continue
                                if isinstance(parent, DependencyArg):
-                                       if self._dynamic_config.digraph.parent_nodes(parent):
-                                               selected_parent = parent
-                                               child = node
-                                       else:
-                                               dep_chain.append(
-                                                       (_unicode_decode("%s") % (parent,), "argument"))
-                                               selected_parent = None
-                                       break
+                                       parent_arg = parent
                                else:
+                                       if isinstance(parent, Package) and \
+                                               parent.operation == "merge":
+                                               parent_merge = parent
                                        if unsatisfied_dependency and node is start_node:
                                                # Make sure that pkg doesn't satisfy parent's dependency.
                                                # This ensures that we select the correct parent for use
@@ -2396,11 +2396,21 @@ class depgraph(object):
                                                                atom_set = InternalPackageSet(initial_atoms=(atom,))
                                                                if not atom_set.findAtomForPackage(start_node):
                                                                        selected_parent = parent
-                                                                       child = node
                                                                break
                                        else:
                                                selected_parent = parent
-                                               child = node
+
+                       if parent_merge is not None:
+                               # Prefer parent in the merge list (bug #354747).
+                               selected_parent = parent_merge
+                       elif parent_arg is not None:
+                               if self._dynamic_config.digraph.parent_nodes(parent_arg):
+                                       selected_parent = parent_arg
+                               else:
+                                       dep_chain.append(
+                                               (_unicode_decode("%s") % (parent,), "argument"))
+                                       selected_parent = None
+
                        node = selected_parent
                return dep_chain