Bug #198129 - Prevent SLOT atoms like sys-devel/binutils:0

from being inappropriately recorded in the world file when
USE=multislot is enabled.

svn path=/main/trunk/; revision=8438

diff --git a/pym/_emerge/__init__.py b/pym/_emerge/__init__.py
index 933c4ce9b107049f21b0b228f99df1d7cb227426..67f8d7306386e2604f1a7d89a13690293e756d75 100644 (file)
--- a/pym/_emerge/__init__.py
+++ b/pym/_emerge/__init__.py
@@ -631,19 +631,37 @@ def create_world_atom(pkg_key, metadata, args_set, root_config):
                # If the user gave a specific atom, store it as a
                # slot atom in the world file.
                slot_atom = "%s:%s" % (cp, metadata["SLOT"])
-               # First verify the slot is in the portage tree to avoid
-               # adding a bogus slot like that produced by multislot.
+
+               # For USE=multislot, there are a couple of cases to
+               # handle here:
+               #
+               # 1) SLOT="0", but the real SLOT spontaneously changed to some
+               #    unknown value, so just record an unslotted atom.
+               #
+               # 2) SLOT comes from an installed package and there is no
+               #    matching SLOT in the portage tree.
+               #
+               # Make sure that the slot atom is available in either the
+               # portdb or the vardb, since otherwise the user certainly
+               # doesn't want the SLOT atom recorded in the world file
+               # (case 1 above).  If it's only available in the vardb,
+               # the user may be trying to prevent a USE=multislot
+               # package from being removed by --depclean (case 2 above).
+
                mydb = portdb
                if not portdb.match(slot_atom):
+                       # SLOT seems to come from an installed multislot package
                        mydb = vardb
-               # Now verify that the argument is precise
-               # enough to identify a specific slot.
-               matches = mydb.match(arg_atom)
-               matched_slots = set()
-               for cpv in matches:
-                       matched_slots.add(mydb.aux_get(cpv, ["SLOT"])[0])
-               if len(matched_slots) == 1:
-                       new_world_atom = slot_atom
+               if mydb.match(slot_atom):
+                       # Now verify that the argument is precise
+                       # enough to identify a specific slot.
+                       matches = mydb.match(arg_atom)
+                       matched_slots = set()
+                       for cpv in matches:
+                               matched_slots.add(mydb.aux_get(cpv, ["SLOT"])[0])
+                       if len(matched_slots) == 1:
+                               new_world_atom = slot_atom
+
        if new_world_atom == sets["world"].findAtomForPackage(pkg_key, metadata):
                # Both atoms would be identical, so there's nothing to add.
                return None