Bug #233253 - Implement a @downgrade set which selects packages for which

the highest visible ebuild version is lower than the currently installed
version. This is useful if you have installed packages from an overlay and
you want to downgrade to the highest visible after removing the overlay,
even though the packages that will be dowgraded are not necessarily masked
in any way.

svn path=/main/trunk/; revision=11299

3 files changed, 55 insertions, 1 deletions

diff --git a/cnf/sets.conf b/cnf/sets.conf
index eda003f43..b3dc132fa 100644
--- a/cnf/sets.conf
+++ b/cnf/sets.conf
@@ -53,3 +53,9 @@ inherits = cvs darcs git mercurial subversion
 class = portage.sets.dbapi.OwnerSet
 world-candidate = False
 files = /lib/modules
+
+# Installed packages for which the highest visible ebuild
+# version is lower than the currently installed version.
+[downgrade]
+class = portage.sets.dbapi.DowngradeSet
+world-candidate = False
diff --git a/doc/config/sets.docbook b/doc/config/sets.docbook
index 16fe54107..7cccbbc93 100644
--- a/doc/config/sets.docbook
+++ b/doc/config/sets.docbook
@@ -479,6 +479,15 @@
 		</itemizedlist>
 		</para>
 		</sect2>
+		<sect2 id='config-set-classes-DowngradeSet'>
+		<title>portage.sets.dbapi.DowngradeSet</title>
+		<para>
+		Package set which contains all packages
+		for which the highest visible ebuild version is lower than
+		the currently installed version.
+		This class doesn't support any extra options.
+		</para>
+		</sect2>
 		<sect2 id='config-set-classes-PreservedLibraryConsumerSet'>
 		<title>portage.sets.libs.PreservedLibraryConsumerSet</title>
 		<para>
@@ -518,6 +527,7 @@
 	<listitem><varname>preserved-rebuild</varname>: uses <classname>PreservedLibraryConsumerSet</classname></listitem>
 	<listitem><varname>live-rebuild</varname>: uses <classname>InheritSet</classname></listitem>
 	<listitem><varname>module-rebuild</varname>: uses <classname>OwnerSet</classname></listitem>
+	<listitem><varname>downgrade</varname>: uses <classname>DowngradeSet</classname></listitem>
 	</itemizedlist>
 	Additionally the default configuration includes a multi set section based on
 	the <classname>StaticFileSet</classname> defaults that creates a set for each 
diff --git a/pym/portage/sets/dbapi.py b/pym/portage/sets/dbapi.py
index 66c014272..28632f43b 100644
--- a/pym/portage/sets/dbapi.py
+++ b/pym/portage/sets/dbapi.py
@@ -2,7 +2,7 @@
 # Distributed under the terms of the GNU General Public License v2
 # $Id$
 
-from portage.versions import catpkgsplit, catsplit
+from portage.versions import catpkgsplit, catsplit, pkgcmp
 from portage.sets.base import PackageSet
 from portage.sets import SetConfigError, get_boolean
 
@@ -105,6 +105,44 @@ class InheritSet(PackageSet):
 
 	singleBuilder = classmethod(singleBuilder)
 
+class DowngradeSet(PackageSet):
+
+	_operations = ["merge", "unmerge"]
+
+	description = "Package set which contains all packages " + \
+		"for which the highest visible ebuild version is lower than " + \
+		"the currently installed version."
+
+	def __init__(self, portdb=None, vardb=None):
+		super(DowngradeSet, self).__init__()
+		self._portdb = portdb
+		self._vardb = vardb
+
+	def load(self):
+		atoms = []
+		xmatch = self._portdb.xmatch
+		xmatch_level = "bestmatch-visible"
+		cp_list = self._vardb.cp_list
+		aux_get = self._vardb.aux_get
+		aux_keys = ["SLOT"]
+		for cp in self._vardb.cp_all():
+			for cpv in cp_list(cp):
+				slot, = aux_get(cpv, aux_keys)
+				slot_atom = "%s:%s" % (cp, slot)
+				ebuild = xmatch(xmatch_level, slot_atom)
+				ebuild_split = catpkgsplit(ebuild)[1:]
+				installed_split = catpkgsplit(cpv)[1:]
+				if pkgcmp(installed_split, ebuild_split) > 0:
+					atoms.append(slot_atom)
+
+		self._setAtoms(atoms)
+
+	def singleBuilder(cls, options, settings, trees):
+		return cls(portdb=trees["porttree"].dbapi,
+			vardb=trees["vartree"].dbapi)
+
+	singleBuilder = classmethod(singleBuilder)
+
 class CategorySet(PackageSet):
 	_operations = ["merge", "unmerge"]