From 60d7d3cf4364a1cc41cf98b57359a0faf1fdc5bd Mon Sep 17 00:00:00 2001
From: Zac Medico <zmedico@gentoo.org>
Date: Wed, 19 Sep 2012 12:48:24 -0700
Subject: [PATCH] update_dbentry: improve slotmove support

This could be especially useful for "built" slot operator deps, in
order to avoid having a slotmove trigger unnecessary rebuilds.
---
 .../tests/update/test_update_dbentry.py       | 26 +++++++++++
 pym/portage/update.py                         | 46 ++++++++++++++++---
 2 files changed, 65 insertions(+), 7 deletions(-)

diff --git a/pym/portage/tests/update/test_update_dbentry.py b/pym/portage/tests/update/test_update_dbentry.py
index e13cfed74..ac16a8ae3 100644
--- a/pym/portage/tests/update/test_update_dbentry.py
+++ b/pym/portage/tests/update/test_update_dbentry.py
@@ -6,14 +6,40 @@ import textwrap
 
 import portage
 from portage import os
+from portage.dep import Atom
 from portage.tests import TestCase
 from portage.tests.resolver.ResolverPlayground import ResolverPlayground
+from portage.update import update_dbentry
 from portage.util import ensure_dirs
 from portage._global_updates import _do_global_updates
 
 class UpdateDbentryTestCase(TestCase):
 
 	def testUpdateDbentryTestCase(self):
+		cases = (
+			(("slotmove", Atom("dev-libs/A"), "0", "1"), "1",
+				"  dev-libs/A:0  ", "  dev-libs/A:1  "),
+
+			(("slotmove", Atom("dev-libs/A"), "0", "1"), "1",
+				"  >=dev-libs/A-1:0  ", "  >=dev-libs/A-1:1  "),
+
+			(("slotmove", Atom("dev-libs/A"), "0", "1"), "5_pre2",
+				"  dev-libs/A:0/1=[foo]  ", "  dev-libs/A:1/1=[foo]  "),
+
+			(("slotmove", Atom("dev-libs/A"), "0", "1"), "5_pre2",
+				"  dev-libs/A:0/1[foo]  ", "  dev-libs/A:1/1[foo]  "),
+
+			(("slotmove", Atom("dev-libs/A"), "0", "1"), "5_pre2",
+				"  dev-libs/A:0/0[foo]  ", "  dev-libs/A:1/1[foo]  "),
+
+			(("slotmove", Atom("dev-libs/A"), "0", "1"), "5_pre2",
+				"  dev-libs/A:0=[foo]  ", "  dev-libs/A:1=[foo]  "),
+		)
+		for update_cmd, eapi, input_str, output_str in cases:
+			result = update_dbentry(update_cmd, input_str, eapi=eapi)
+			self.assertEqual(result, output_str)
+
+	def testUpdateDbentryDbapiTestCase(self):
 
 		ebuilds = {
 
diff --git a/pym/portage/update.py b/pym/portage/update.py
index 121e95720..017f71f62 100644
--- a/pym/portage/update.py
+++ b/pym/portage/update.py
@@ -22,7 +22,7 @@ portage.proxy.lazyimport.lazyimport(globals(),
 )
 
 from portage.const import USER_CONFIG_PATH
-from portage.dep import _get_slot_re
+from portage.dep import Atom, _get_slot_re
 from portage.eapi import _get_eapi_attrs
 from portage.exception import DirectoryNotFound, InvalidAtom, PortageException
 from portage.localization import _
@@ -57,12 +57,44 @@ def update_dbentry(update_cmd, mycontent, eapi=None):
 					return "".join(matchobj.groups())
 			mycontent = re.sub("(%s-)(\\S*)" % old_value, myreplace, mycontent)
 	elif update_cmd[0] == "slotmove" and update_cmd[1].operator is None:
-		pkg, origslot, newslot = update_cmd[1:]
-		old_value = "%s:%s" % (pkg, origslot)
-		if old_value in mycontent:
-			old_value = re.escape(old_value)
-			new_value = "%s:%s" % (pkg, newslot)
-			mycontent = re.sub(old_value+"($|\\s)", new_value+"\\1", mycontent)
+		orig_atom, origslot, newslot = update_cmd[1:]
+		orig_cp = orig_atom.cp
+
+		# We don't support versioned slotmove atoms here, since it can be
+		# difficult to determine if the version constraints really match
+		# the atoms that we're trying to update.
+		if orig_atom.version is None and orig_cp in mycontent:
+			# this split preserves existing whitespace
+			split_content = re.split(r'(\s+)', mycontent)
+			modified = False
+			for i, token in enumerate(split_content):
+				if orig_cp not in token:
+					continue
+				try:
+					atom = Atom(token, eapi=eapi)
+				except InvalidAtom:
+					continue
+				if atom.cp != orig_cp:
+					continue
+				if atom.slot is None or atom.slot != origslot:
+					continue
+
+				slot_part = newslot
+				if atom.sub_slot is not None:
+					if atom.sub_slot == origslot:
+						sub_slot = newslot
+					else:
+						sub_slot = atom.sub_slot
+					slot_part += "/" + sub_slot
+				if atom.slot_operator is not None:
+					slot_part += atom.slot_operator
+
+				split_content[i] = atom.with_slot(slot_part)
+				modified = True
+
+			if modified:
+				mycontent = "".join(split_content)
+
 	return mycontent
 
 def update_dbentries(update_iter, mydata, eapi=None):
-- 
2.26.2