depgraph: refactor virtual slot --update code

This re-implements the change from commit
21330075f07248765016e104b3ba8216903f1ecb in order to avoid executing
unnessary virtual slot expansion code when the given atom specifies a
slot or --update is enabled.

diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index 3cb85dcef1e00458f4709093106ff4c0d8ad6ab9..2c3960808b84dabc13534d2101ff97dec3806e60 100644 (file)
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -6530,32 +6530,34 @@ class _dep_check_composite_db(dbapi):
                ret = self._match_cache.get(atom)
                if ret is not None:
                        return ret[:]
+
+               ret = []
                pkg, existing = self._depgraph._select_package(self._root, atom)
-               if not pkg:
-                       ret = []
-               else:
-                       # Return the highest available from select_package() as well as
-                       # any matching slots in the graph db.
+
+               if pkg is not None and self._visible(pkg):
+                       self._cpv_pkg_map[pkg.cpv] = pkg
+                       ret.append(pkg.cpv)
+
+               if pkg is not None and \
+                       atom.slot is None and \
+                       "--update" not in self._depgraph._frozen_config.myopts and \
+                       pkg.cp.startswith("virtual/"):
+                       # For new-style virtual lookahead that occurs inside dep_check()
+                       # for bug #141118, examine all slots. This is needed so that newer
+                       # slots will not unnecessarily be pulled in when a satisfying lower
+                       # slot is already installed. For example, if virtual/jdk-1.5 is
+                       # satisfied via gcj-jdk then there's no need to pull in a newer
+                       # slot to satisfy a virtual/jdk dependency, unless --update is
+                       # enabled.
                        slots = set()
-                       slots.add(pkg.metadata["SLOT"])
-                       if pkg.cp.startswith("virtual/"):
-                               # For new-style virtual lookahead that occurs inside
-                               # dep_check(), examine all slots. This is needed
-                               # so that newer slots will not unnecessarily be pulled in
-                               # when a satisfying lower slot is already installed. For
-                               # example, if virtual/jdk-1.4 is satisfied via kaffe then
-                               # there's no need to pull in a newer slot to satisfy a
-                               # virtual/jdk dependency.
-                               for virt_pkg in self._depgraph._iter_match_pkgs_any(
-                                       self._depgraph._frozen_config.roots[self._root], atom):
-                                       if virt_pkg.cp != pkg.cp:
-                                               continue
-                                       slots.add(virt_pkg.slot)
-                       ret = []
-                       if self._visible(pkg):
-                               self._cpv_pkg_map[pkg.cpv] = pkg
-                               ret.append(pkg.cpv)
-                       slots.remove(pkg.metadata["SLOT"])
+                       slots.add(pkg.slot)
+                       for virt_pkg in self._depgraph._iter_match_pkgs_any(
+                               self._depgraph._frozen_config.roots[self._root], atom):
+                               if virt_pkg.cp != pkg.cp:
+                                       continue
+                               slots.add(virt_pkg.slot)
+
+                       slots.remove(pkg.slot)
                        while slots:
                                slot_atom = atom.with_slot(slots.pop())
                                pkg, existing = self._depgraph._select_package(
@@ -6569,10 +6571,6 @@ class _dep_check_composite_db(dbapi):
 
                        if len(ret) > 1:
                                self._cpv_sort_ascending(ret)
-                               if "--update" in self._depgraph._frozen_config.myopts:
-                                       # With --update, we want to force selection of
-                                       # the highest available version.
-                                       ret = [ret[-1]]
 
                self._match_cache[atom] = ret
                return ret[:]