Bug #275047 - Split _emerge/__init__.py into smaller pieces (part 5).

Thanks to Sebastian Mingramm (few) <s.mingramm@gmx.de> for this patch.

svn path=/main/trunk/; revision=13672

1 files changed, 91 insertions, 0 deletions

diff --git a/pym/_emerge/create_world_atom.py b/pym/_emerge/create_world_atom.py
new file mode 100644
index 000000000..1b13c4058
--- /dev/null
+++ b/pym/_emerge/create_world_atom.py
@@ -0,0 +1,91 @@
+try:
+	import portage
+except ImportError:
+	from os import path as osp
+	import sys
+	sys.path.insert(0, osp.join(osp.dirname(osp.dirname(osp.realpath(__file__))), "pym"))
+	import portage
+
+def create_world_atom(pkg, args_set, root_config):
+	"""Create a new atom for the world file if one does not exist.  If the
+	argument atom is precise enough to identify a specific slot then a slot
+	atom will be returned. Atoms that are in the system set may also be stored
+	in world since system atoms can only match one slot while world atoms can
+	be greedy with respect to slots.  Unslotted system packages will not be
+	stored in world."""
+
+	arg_atom = args_set.findAtomForPackage(pkg)
+	if not arg_atom:
+		return None
+	cp = portage.dep_getkey(arg_atom)
+	new_world_atom = cp
+	sets = root_config.sets
+	portdb = root_config.trees["porttree"].dbapi
+	vardb = root_config.trees["vartree"].dbapi
+	available_slots = set(portdb.aux_get(cpv, ["SLOT"])[0] \
+		for cpv in portdb.match(cp))
+	slotted = len(available_slots) > 1 or \
+		(len(available_slots) == 1 and "0" not in available_slots)
+	if not slotted:
+		# check the vdb in case this is multislot
+		available_slots = set(vardb.aux_get(cpv, ["SLOT"])[0] \
+			for cpv in vardb.match(cp))
+		slotted = len(available_slots) > 1 or \
+			(len(available_slots) == 1 and "0" not in available_slots)
+	if slotted and arg_atom != cp:
+		# If the user gave a specific atom, store it as a
+		# slot atom in the world file.
+		slot_atom = pkg.slot_atom
+
+		# 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
+		# If there is no installed package matching the SLOT atom,
+		# it probably changed SLOT spontaneously due to USE=multislot,
+		# so just record an unslotted atom.
+		if vardb.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):
+		# Both atoms would be identical, so there's nothing to add.
+		return None
+	if not slotted:
+		# Unlike world atoms, system atoms are not greedy for slots, so they
+		# can't be safely excluded from world if they are slotted.
+		system_atom = sets["system"].findAtomForPackage(pkg)
+		if system_atom:
+			if not portage.dep_getkey(system_atom).startswith("virtual/"):
+				return None
+			# System virtuals aren't safe to exclude from world since they can
+			# match multiple old-style virtuals but only one of them will be
+			# pulled in by update or depclean.
+			providers = portdb.mysettings.getvirtuals().get(
+				portage.dep_getkey(system_atom))
+			if providers and len(providers) == 1 and providers[0] == cp:
+				return None
+	return new_world_atom
+