want_restart_for_use_change: backtrack only if needed (bug 632598)
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
Acked-by: Brian Dolbec <dolsen@gentoo.org>
diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index b0149c4..0b9b98d 100644
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -5972,11 +5972,16 @@
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 0000000..83edeaf
--- /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()
