[gentoo-portage-dev] [PATCH] emerge: add --ignore-world [ y | n ] option (bug 608564)

[Zac Medico]

Ignore the @world package set and its dependencies. This may be useful
if there is a desire to perform an action even though it might break
the dependencies of some installed packages (it might also remove
installed packages in order to solve blockers). This also alters the
behavior of --complete-graph options so that only deep dependencies
of packages given as arguments are included in the dependency graph.
This option may be useful as an alternative to --nodeps in cases where
it is desirable to account for dependencies of packages given as
arguments.

Bug: https://bugs.gentoo.org/608564
---
 man/emerge.1                                      | 17 +++++++++++++++++
 pym/_emerge/create_depgraph_params.py             |  4 ++++
 pym/_emerge/depgraph.py                           |  8 ++++++--
 pym/_emerge/main.py                               |  9 +++++++++
 pym/portage/tests/resolver/test_complete_graph.py | 18 ++++++++++++++++++
 5 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/man/emerge.1 b/man/emerge.1
index a17b65ed2..01ce62e51 100644
--- a/man/emerge.1
+++ b/man/emerge.1
@@ -630,6 +630,23 @@ Therefore, \fB\-\-usepkgonly\fR (or \fB\-\-getbinpkgonly\fR) must be
 used in order to enable soname depedency resolution when installing
 packages.
 .TP
+.BR "\-\-ignore\-world [ y | n ]"
+Ignore the @world package set and its dependencies. This may be useful
+if there is a desire to perform an action even though it might break
+the dependencies of some installed packages (it might also remove
+installed packages in order to solve blockers). This also alters the
+behavior of \fB\-\-complete\-graph\fR options so that only deep
+dependencies of packages given as arguments are included in the
+dependency graph. This option may be useful as an alternative to
+\fB\-\-nodeps\fR in cases where it is desirable to account for
+dependencies of packages given as arguments.
+
+\fBWARNING:\fR
+This option is intended to be used only with great caution, since it is
+possible for it to make nonsensical changes which may lead to system
+breakage. Therefore, it is advisable to use \fB\-\-ask\fR together with
+this option.
+.TP
 .BR \-j\ [JOBS] ", "  \-\-jobs[=JOBS]
 Specifies the number of packages to build simultaneously. If this option is
 given without an argument, emerge will not limit the number of jobs that can
diff --git a/pym/_emerge/create_depgraph_params.py b/pym/_emerge/create_depgraph_params.py
index fc7fa60d7..0405011fd 100644
--- a/pym/_emerge/create_depgraph_params.py
+++ b/pym/_emerge/create_depgraph_params.py
@@ -26,6 +26,7 @@ def create_depgraph_params(myopts, myaction):
 	# ignore_soname_deps: ignore the soname dependencies of built
 	#   packages, so that they do not trigger dependency resolution
 	#   failures, or cause packages to be rebuilt or replaced.
+	# ignore_world: ignore the @world package set and its dependencies
 	# with_test_deps: pull in test deps for packages matched by arguments
 	# changed_deps: rebuild installed packages with outdated deps
 	# changed_deps_report: report installed packages with outdated deps
@@ -56,6 +57,9 @@ def create_depgraph_params(myopts, myaction):
 		myparams["selective"] = True
 		return myparams
 
+	if myopts.get('--ignore-world') is True:
+		myparams['ignore_world'] = True
+
 	rebuild_if_new_slot = myopts.get('--rebuild-if-new-slot')
 	if rebuild_if_new_slot is not None:
 		myparams['rebuild_if_new_slot'] = rebuild_if_new_slot
diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index 6c728684f..f7ea27c37 100644
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -163,7 +163,10 @@ class _frozen_depgraph_config(object):
 				self.trees[myroot]["bintree"] = DummyTree(
 					DbapiProvidesIndex(trees[myroot]["bintree"].dbapi))
 
-		self._required_set_names = set(["world"])
+		if params.get("ignore_world", False):
+			self._required_set_names = set()
+		else:
+			self._required_set_names = set(["world"])
 
 		atoms = ' '.join(myopts.get("--exclude", [])).split()
 		self.excluded_pkgs = _wildcard_set(atoms)
@@ -7554,6 +7557,7 @@ class depgraph(object):
 		ignored_uninstall_tasks = set()
 		have_uninstall_task = False
 		complete = "complete" in self._dynamic_config.myparams
+		ignore_world = self._dynamic_config.myparams.get("ignore_world", False)
 		asap_nodes = []
 
 		def get_nodes(**kwargs):
@@ -7971,7 +7975,7 @@ class depgraph(object):
 					# detected as early as possible, which makes it possible
 					# to avoid calling self._complete_graph() when it is
 					# unnecessary due to blockers triggering an abortion.
-					if not complete:
+					if not (complete or ignore_world):
 						# For packages in the world set, go ahead an uninstall
 						# when necessary, as long as the atom will be satisfied
 						# in the final state.
diff --git a/pym/_emerge/main.py b/pym/_emerge/main.py
index fbc2ce01c..5b48d32a4 100644
--- a/pym/_emerge/main.py
+++ b/pym/_emerge/main.py
@@ -146,6 +146,7 @@ def insert_optional_args(args):
 		'--fuzzy-search'         : y_or_n,
 		'--getbinpkg'            : y_or_n,
 		'--getbinpkgonly'        : y_or_n,
+		'--ignore-world'         : y_or_n,
 		'--jobs'       : valid_integers,
 		'--keep-going'           : y_or_n,
 		'--load-average'         : valid_floats,
@@ -503,6 +504,11 @@ def parse_opts(tmpcmdline, silent=False):
 			"choices": y_or_n
 		},
 
+		"--ignore-world": {
+			"help"    : "ignore the @world package set and its dependencies",
+			"choices" : true_y_or_n
+		},
+
 		"--jobs": {
 
 			"shortopt" : "-j",
@@ -919,6 +925,9 @@ def parse_opts(tmpcmdline, silent=False):
 	else:
 		myoptions.getbinpkgonly = None
 
+	if myoptions.ignore_world in true_y:
+		myoptions.ignore_world = True
+
 	if myoptions.keep_going in true_y:
 		myoptions.keep_going = True
 	else:
diff --git a/pym/portage/tests/resolver/test_complete_graph.py b/pym/portage/tests/resolver/test_complete_graph.py
index 95b1f8809..d02e57582 100644
--- a/pym/portage/tests/resolver/test_complete_graph.py
+++ b/pym/portage/tests/resolver/test_complete_graph.py
@@ -59,6 +59,12 @@ class CompleteGraphTestCase(TestCase):
 				success = True,
 			),
 
+			ResolverPlaygroundTestCase(
+				["dev-libs/libxml2"],
+				options = {"--ignore-world" : True},
+				mergelist = ["dev-libs/libxml2-2.8.0"],
+				success = True,
+			),
 		)
 
 		playground = ResolverPlayground(ebuilds=ebuilds,
@@ -99,6 +105,12 @@ class CompleteGraphTestCase(TestCase):
 			),
 			ResolverPlaygroundTestCase(
 				[">=sys-libs/x-2"],
+				options = {"--ignore-world" : True},
+				mergelist = ["sys-libs/x-2"],
+				success = True,
+			),
+			ResolverPlaygroundTestCase(
+				[">=sys-libs/x-2"],
 				options = {"--complete-graph-if-new-ver" : "y"},
 				mergelist = ["sys-libs/x-2"],
 				slot_collision_solutions = [],
@@ -112,6 +124,12 @@ class CompleteGraphTestCase(TestCase):
 			),
 			ResolverPlaygroundTestCase(
 				["<sys-libs/x-1"],
+				options = {"--ignore-world" : True},
+				mergelist = ["sys-libs/x-0.1"],
+				success = True,
+			),
+			ResolverPlaygroundTestCase(
+				["<sys-libs/x-1"],
 				options = {"--complete-graph-if-new-ver" : "y"},
 				mergelist = ["sys-libs/x-0.1"],
 				slot_collision_solutions = [],
-- 
2.13.6