Re: [gentoo-portage-dev] [PATCH] depgraph: avoid missed update with slot operator and circ dep (bug 612874)

[Brian Dolbec]

On Fri, 17 Mar 2017 01:18:19 -0700
Zac Medico <zmedico@g.o> wrote:

> Fix check_reverse_dependencies to ignore direct circular dependencies,
> since these dependencies tend to prevent updates of packages. This
> solves a missed update from llvm:0 to llvm:4 when clang is not in the
> world file, as demonstrated by the included test case.
>
> X-Gentoo-bug: 612874
> X-Gentoo-bug-url: https://bugs.gentoo.org/show_bug.cgi?id=612874
> ---
>  pym/_emerge/depgraph.py                            | 31
> ++++++++++++----- .../resolver/test_slot_operator_exclusive_slots.py
> | 39 ++++++++++++++++++++++
> pym/portage/util/digraph.py                        |  6 ++++ 3 files
> changed, 68 insertions(+), 8 deletions(-)
>
> diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
> index f4145d0..e94b96c 100644
> --- a/pym/_emerge/depgraph.py
> +++ b/pym/_emerge/depgraph.py
> @@ -1844,14 +1844,29 @@ class depgraph(object):
>  					if (not
> self._too_deep(parent.depth) and not
> self._frozen_config.excluded_pkgs. findAtomForPackage(parent,
> -
> modified_use=self._pkg_use_enabled(parent)) and
> -
> (self._upgrade_available(parent) or
> -						(parent.installed
> and self._in_blocker_conflict(parent)))):
> -						# This parent may be
> irrelevant, since an
> -						# update is
> available (see bug 584626), or
> -						# it could be
> uninstalled in order to solve
> -						# a blocker conflict
> (bug 612772).
> -						continue
> +
> modified_use=self._pkg_use_enabled(parent))):
> +						# Check for common
> reasons that the parent's
> +						# dependency might
> be irrelevant.
> +						if
> self._upgrade_available(parent):
> +							# This
> parent could be replaced by
> +							# an upgrade
> (bug 584626).
> +							continue
> +						if parent.installed
> and self._in_blocker_conflict(parent):
> +							# This
> parent could be uninstalled in order
> +							# to solve a
> blocker conflict (bug 612772).
> +							continue
> +						if
> self._dynamic_config.digraph.has_edge(parent,
> +
> existing_pkg):
> +							# There is a
> direct circular dependency between
> +							# parent and
> existing_pkg. This type of
> +							#
> relationship tends to prevent updates
> +							# of
> packages (bug 612874). Since candidate_pkg
> +							# is
> available, we risk a missed update if we
> +							# don't try
> to eliminate this parent from the
> +							# graph.
> Therefore, we give candidate_pkg a
> +							# chance,
> and assume that it will be masked
> +							# by
> backtracking if necessary.
> +							continue
>
>  				atom_set =
> InternalPackageSet(initial_atoms=(atom,), allow_repo=True)
> diff --git
> a/pym/portage/tests/resolver/test_slot_operator_exclusive_slots.py
> b/pym/portage/tests/resolver/test_slot_operator_exclusive_slots.py
> index 2ab379c..689ed31 100644 ---
> a/pym/portage/tests/resolver/test_slot_operator_exclusive_slots.py
> +++
> b/pym/portage/tests/resolver/test_slot_operator_exclusive_slots.py @@
> -107,3 +107,42 @@ class SlotOperatorExclusiveSlotsTestCase(TestCase):
> test_case.fail_msg) finally: playground.cleanup() +
> +
> +		world = ["media-libs/mesa"]
> +
> +		test_cases = (
> +
> +			# Test bug #612874, where a direct circular
> dependency
> +			# between llvm-3.9.1 and clang-3.9.1-r100
> causes a
> +			# missed update from llvm:0 to llvm:4. Since
> llvm:4 does
> +			# not have a dependency on clang, the
> upgrade from llvm:0
> +			# to llvm:4 makes the installed
> sys-devel/clang-3.9.1-r100
> +			# instance eligible for removal by emerge
> --depclean, which
> +			# explains why clang does not appear in the
> mergelist.
> +			ResolverPlaygroundTestCase(
> +				["@world"],
> +				options = {"--update": True,
> "--deep": True},
> +				success = True,
> +				ambiguous_merge_order = True,
> +				mergelist = [
> +					'sys-devel/llvm-4.0.0',
> +					(
> +						'media-libs/mesa-17.0.1',
> +						'[uninstall]sys-devel/llvm-3.9.1',
> +						'!sys-devel/llvm:0',
> +					)
> +				],
> +			),
> +
> +		)
> +
> +		playground = ResolverPlayground(ebuilds=ebuilds,
> +			installed=installed, world=world)
> +		try:
> +			for test_case in test_cases:
> +				playground.run_TestCase(test_case)
> +
> self.assertEqual(test_case.test_success, True,
> +					test_case.fail_msg)
> +		finally:
> +			playground.cleanup()
> diff --git a/pym/portage/util/digraph.py b/pym/portage/util/digraph.py
> index 4a9cb43..b6be0c9 100644
> --- a/pym/portage/util/digraph.py
> +++ b/pym/portage/util/digraph.py
> @@ -93,6 +93,12 @@ class digraph(object):
>  			del self.nodes[node]
>  		self.order = order
>
> +	def has_edge(self, child, parent):
> +		"""
> +		Return True if the given edge exists.
> +		"""
> +		return child in self.nodes[parent][0]
> +
>  	def remove_edge(self, child, parent):
>  		"""
>  		Remove edge in the direction from child to parent.
> Note that it is


Looks good

-- 
Brian Dolbec <dolsen>