Re: [gentoo-portage-dev] [PATCH] want_restart_for_use_change: backtrack only if needed (bug 632598)

[Brian Dolbec]

On Sat, 30 Sep 2017 19:48:21 -0700
Zac Medico <zmedico@g.o> wrote:

> Only backtrack if changes break a USE dependency. Prior
> to this fix, the included test case succeeded only with
> a --backtrack setting of 3 or more, but now it succeeds
> with a --backtrack setting of 2.
>
> X-Gentoo-bug: 632598
> X-Gentoo-bug-url: https://bugs.gentoo.org/632598
> ---
>  pym/_emerge/depgraph.py                            | 13 +++-
>  .../resolver/test_autounmask_use_backtrack.py      | 86
> ++++++++++++++++++++++ 2 files changed, 95 insertions(+), 4
> deletions(-) create mode 100644
> pym/portage/tests/resolver/test_autounmask_use_backtrack.py
>
> diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
> index b0149c4dc..0b9b98dbb 100644
> --- a/pym/_emerge/depgraph.py
> +++ b/pym/_emerge/depgraph.py
> @@ -5972,11 +5972,16 @@ class depgraph(object):
>
>  			new_use, changes =
> self._dynamic_config._needed_use_config_changes.get(pkg) for ppkg,
> atom in parent_atoms:
> -				if not atom.use or \
> -					not any(x in
> atom.use.required for x in changes):
> +				if not atom.use:
>  					continue
> -				else:
> -					return True
> +
> +				# Backtrack only if changes break a
> USE dependency.
> +				enabled = atom.use.enabled
> +				disabled = atom.use.disabled
> +				for k, v in changes.items():
> +					want_enabled = k in enabled
> +					if (want_enabled or k in
> disabled) and want_enabled != v:
> +						return True
>
>  			return False
>
> diff --git
> a/pym/portage/tests/resolver/test_autounmask_use_backtrack.py
> b/pym/portage/tests/resolver/test_autounmask_use_backtrack.py new
> file mode 100644 index 000000000..83edeafa4 --- /dev/null
> +++ b/pym/portage/tests/resolver/test_autounmask_use_backtrack.py
> @@ -0,0 +1,86 @@
> +# Copyright 2017 Gentoo Foundation
> +# Distributed under the terms of the GNU General Public License v2
> +
> +from portage.tests import TestCase
> +from portage.tests.resolver.ResolverPlayground import (
> +	ResolverPlayground,
> +	ResolverPlaygroundTestCase,
> +)
> +
> +class AutounmaskUseBacktrackTestCase(TestCase):
> +
> +	def testAutounmaskUseBacktrack(self):
> +		ebuilds = {
> +			'dev-libs/A-1': {
> +				'EAPI': '6',
> +				'RDEPEND': 'dev-libs/C',
> +			},
> +			'dev-libs/A-2': {
> +				'EAPI': '6',
> +				'RDEPEND': 'dev-libs/C[y]',
> +			},
> +			'dev-libs/A-3': {
> +				'EAPI': '6',
> +				'RDEPEND': 'dev-libs/C',
> +			},
> +			'dev-libs/B-1': {
> +				'EAPI': '6',
> +				'RDEPEND': '<dev-libs/A-3',
> +			},
> +			'dev-libs/C-1': {
> +				'EAPI': '6',
> +				'IUSE': 'x y z',
> +			},
> +			'dev-libs/D-1': {
> +				'EAPI': '6',
> +				'RDEPEND': '>=dev-libs/A-2
> dev-libs/C[x]',
> +			},
> +		}
> +
> +		installed = {
> +			'dev-libs/A-1': {
> +				'EAPI': '6',
> +				'RDEPEND': 'dev-libs/C',
> +			},
> +			'dev-libs/B-1': {
> +				'EAPI': '6',
> +				'RDEPEND': '<dev-libs/A-3',
> +			},
> +			'dev-libs/C-1': {
> +				'EAPI': '6',
> +				'IUSE': 'x y z',
> +			},
> +		}
> +
> +		world = ['dev-libs/B']
> +
> +		test_cases = (
> +			# Test bug 632598, where autounmask USE
> changes triggered
> +			# unnecessary backtracking. The following
> case should
> +			# require a --backtrack setting no larger
> than 2.
> +			ResolverPlaygroundTestCase(
> +				['dev-libs/D'],
> +				options={
> +					'--autounmask-backtrack':
> 'y',
> +					'--backtrack': 2,
> +				},
> +				success=False,
> +				ambiguous_merge_order=True,
> +				mergelist=[
> +					('dev-libs/C-1',
> 'dev-libs/A-2'),
> +					'dev-libs/D-1',
> +				],
> +				use_changes={'dev-libs/C-1': {'y':
> True, 'x': True}},
> +			),
> +		)
> +
> +		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()


Looks fine

-- 
Brian Dolbec <dolsen>