Handle binary package IUSE_IMPLICIT divergence (bug 640318)

Since profile IUSE_IMPLICIT settings may diverge from those
that a binary package was built with, consider members of
built USE settings to be members of IUSE_EFFECTIVE. Only do
this for EAPIs that support IUSE_EFFECTIVE, since built USE
settings for earlier EAPIs may contain a large number of
irrelevant flags.

Note that the binary package may be remote, so it's only
possible to rely on metadata that is available in the remote
Packages file, and the IUSE_IMPLICIT header in the Packages
file is vulnerable to mutation.

Bug: https://bugs.gentoo.org/640318

3 files changed, 31 insertions, 0 deletions

diff --git a/pym/portage/dbapi/__init__.py b/pym/portage/dbapi/__init__.py
index 95053840d..2574b63df 100644
--- a/pym/portage/dbapi/__init__.py
+++ b/pym/portage/dbapi/__init__.py
@@ -5,6 +5,7 @@ from __future__ import unicode_literals
 
 __all__ = ["dbapi"]
 
+import functools
 import re
 
 import portage
@@ -219,6 +220,10 @@ class dbapi(object):
 		eapi_attrs = _get_eapi_attrs(metadata["EAPI"])
 		if eapi_attrs.iuse_effective:
 			iuse_implicit_match = self.settings._iuse_effective_match
+			if not self._use_mutable:
+				iuse_implicit_match = functools.partial(
+					Package._built_iuse_effective_match,
+					iuse_implicit_match, frozenset(metadata["USE"].split()))
 		else:
 			iuse_implicit_match = self.settings._iuse_implicit_match
 		usealiases = self.settings._use_manager.getUseAliases(pkg)
diff --git a/pym/portage/package/ebuild/config.py b/pym/portage/package/ebuild/config.py
index cd2b009aa..d0225a311 100644
--- a/pym/portage/package/ebuild/config.py
+++ b/pym/portage/package/ebuild/config.py
@@ -1693,6 +1693,12 @@ class config(object):
 			iuse_implicit_match = self._iuse_effective_match
 			portage_iuse = set(self._iuse_effective)
 			portage_iuse.update(explicit_iuse)
+			if built_use is not None:
+				# When the binary package was built, the profile may have
+				# had different IUSE_IMPLICIT settings, so any member of
+				# the built USE setting is considered to be a member of
+				# IUSE_EFFECTIVE (see bug 640318).
+				portage_iuse.update(built_use)
 			self.configdict["pkg"]["IUSE_EFFECTIVE"] = \
 				" ".join(sorted(portage_iuse))
 		else:
diff --git a/pym/portage/tests/dbapi/test_fakedbapi.py b/pym/portage/tests/dbapi/test_fakedbapi.py
index e4f5dd771..19ea9cd00 100644
--- a/pym/portage/tests/dbapi/test_fakedbapi.py
+++ b/pym/portage/tests/dbapi/test_fakedbapi.py
@@ -14,6 +14,20 @@ class TestFakedbapi(TestCase):
 
 	def testFakedbapi(self):
 		packages = (
+			("app-misc/foo-1", {
+				"EAPI"         : "2", # does not support IUSE_EFFECTIVE
+				"IUSE"         : "",
+				"repository"   : "gentoo",
+				"SLOT"         : "1",
+				"USE"          : "missing-iuse",
+			}),
+			("app-misc/foo-2", {
+				"EAPI"         : "5", # supports IUSE_EFFECTIVE
+				"IUSE"         : "",
+				"repository"   : "gentoo",
+				"SLOT"         : "2",
+				"USE"          : "missing-iuse",
+			}),
 			("sys-apps/portage-2.1.10", {
 				"EAPI"         : "2",
 				"IUSE"         : "ipc doc",
@@ -29,6 +43,12 @@ class TestFakedbapi(TestCase):
 		)
 
 		match_tests = (
+			# The missing-iuse match is only intended to work for binary
+			# packages with EAPIs that support IUSE_EFFECTIVE (bug 640318).
+			("app-misc/foo[missing-iuse]",    ["app-misc/foo-2"]),
+			("app-misc/foo[-missing-iuse]",   []),
+			("app-misc/foo",                  ["app-misc/foo-1", "app-misc/foo-2"]),
+
 			("sys-apps/portage:0[ipc]",             ["sys-apps/portage-2.1.10"]),
 			("sys-apps/portage:0[-ipc]",            []),
 			("sys-apps/portage:0[doc]",             []),