Add support to depgraph._select_atoms() to take a "parent" parameter

and use that to try and avoid unresolvable direct circular dependencies
when necessary. Also, make atom selection more consistent with the
graph to solve some cases of bug #1343. This improves the fix from
bug #141118 to work in cases when a virtual is not yet installed but
it has been pulled into the graph. For example, see the case of
in Bug #163801#c17, where we want kaffe to satisfy virtual/jdk-1.4
without an extra jvm being pulled in unnecessarily.

svn path=/main/trunk/; revision=9901

2 files changed, 45 insertions, 3 deletions

diff --git a/pym/_emerge/__init__.py b/pym/_emerge/__init__.py
index e6a8f3dc0..e5c9b0ca9 100644
--- a/pym/_emerge/__init__.py
+++ b/pym/_emerge/__init__.py
@@ -1609,6 +1609,7 @@ class depgraph(object):
 				pass
 			filtered_tree.dbapi = self._dep_check_composite_db(self, myroot)
 			self._filtered_trees[myroot]["porttree"] = filtered_tree
+			self._filtered_trees[myroot]["graph_db"] = graph_tree.dbapi
 
 			# Passing in graph_tree as the vartree here could lead to better
 			# atom selections in some cases by causing atoms for packages that
@@ -2070,7 +2071,7 @@ class depgraph(object):
 				vardb = self.roots[dep_root].trees["vartree"].dbapi
 				try:
 					selected_atoms = self._select_atoms(dep_root,
-						dep_string, myuse=myuse, strict=strict)
+						dep_string, myuse=myuse, parent=pkg, strict=strict)
 				except portage.exception.InvalidDependString, e:
 					show_invalid_depstring_notice(jbigkey, dep_string, str(e))
 					return 0
@@ -2528,7 +2529,7 @@ class depgraph(object):
 		return self._select_atoms_highest_available(*pargs, **kwargs)
 
 	def _select_atoms_highest_available(self, root, depstring,
-		myuse=None, strict=True, trees=None):
+		myuse=None, parent=None, strict=True, trees=None):
 		"""This will raise InvalidDependString if necessary. If trees is
 		None then self._filtered_trees is used."""
 		pkgsettings = self.pkgsettings[root]
@@ -2536,12 +2537,16 @@ class depgraph(object):
 			trees = self._filtered_trees
 		if True:
 			try:
+				if parent is not None:
+					trees[root]["parent"] = parent
 				if not strict:
 					portage.dep._dep_check_strict = False
 				mycheck = portage.dep_check(depstring, None,
 					pkgsettings, myuse=myuse,
 					myroot=root, trees=trees)
 			finally:
+				if parent is not None:
+					trees[root].pop("parent")
 				portage.dep._dep_check_strict = True
 			if not mycheck[0]:
 				raise portage.exception.InvalidDependString(mycheck[1])
diff --git a/pym/portage/__init__.py b/pym/portage/__init__.py
index a20e40ecb..13ded0fea 100644
--- a/pym/portage/__init__.py
+++ b/pym/portage/__init__.py
@@ -5467,6 +5467,8 @@ def dep_zapdeps(unreduced, reduced, myroot, use_binaries=0, trees=None):
 	other = []
 
 	# Alias the trees we'll be checking availability against
+	parent   = trees[myroot].get("parent")
+	graph_db = trees[myroot].get("graph_db")
 	vardb = None
 	if "vartree" in trees[myroot]:
 		vardb = trees[myroot]["vartree"].dbapi
@@ -5528,8 +5530,43 @@ def dep_zapdeps(unreduced, reduced, myroot, use_binaries=0, trees=None):
 					preferred.append(this_choice)
 				else:
 					preferred_any_slot.append(this_choice)
-			else:
+			elif graph_db is None:
 				possible_upgrades.append(this_choice)
+			else:
+				all_in_graph = True
+				for slot_atom in versions:
+					# New-style virtuals have zero cost to install.
+					if not graph_db.match(slot_atom) and \
+						not slot_atom.startswith("virtual/"):
+						all_in_graph = False
+						break
+				if all_in_graph:
+					if parent is None:
+						preferred.append(this_choice)
+					else:
+						# Check if the atom would result in a direct circular
+						# dependency and try to avoid that if it seems likely
+						# to be unresolvable.
+						cpv_slot_list = [parent.cpv_slot]
+						circular_atom = None
+						for atom in atoms:
+							if "!" == atom[:1]:
+								continue
+							if vardb.match(atom):
+								# If the atom is satisfied by an installed
+								# version then it's not a circular dep.
+								continue
+							if dep_getkey(atom) != parent.cp:
+								continue
+							if match_from_list(atom, cpv_slot_list):
+								circular_atom = atom
+								break
+						if circular_atom is None:
+							preferred.append(this_choice)
+						else:
+							other.append(this_choice)
+				else:
+					possible_upgrades.append(this_choice)
 		else:
 			other.append(this_choice)