[gentoo-commits] proj/portage:master commit in: pym/_emerge/, pym/portage/dep/

[Zac Medico]

commit:     cd864267a463769cbd40e058611d2488cc15bf70
Author:     Zac Medico <zmedico <AT> gentoo <DOT> org>
AuthorDate: Mon Oct 31 06:07:06 2016 +0000
Commit:     Zac Medico <zmedico <AT> gentoo <DOT> org>
CommitDate: Thu Nov  3 23:04:08 2016 +0000
URL:        https://gitweb.gentoo.org/proj/portage.git/commit/?id=cd864267

_expand_new_virtuals: constrain output for dep_zapdeps (bug 597752)

Constrain _expand_new_virtuals output in order to avoid incorrect
re-ordering of || deps in the dep_zapdeps function, as reported in
bug 597752.

The incorrect dep_zapdeps behavior involved a problem in the
construction of the _dep_choice.cp_map dictionary inside the
dep_zapdeps function, with this input:

|| ( dev-java/icedtea-bin:8 =virtual/jdk-1.8.0-r3 >=virtual/jdk-1.5 )
( dev-java/icedtea-bin:7 =virtual/jdk-1.7.0-r2 >=virtual/jdk-1.5 )

The cp_map for virtual/jdk-1.7.0-r2 erroneously contained
virtual/jdk-1.8.0-r3 because that was the highest virtual/jdk matched
by the >=virtual/jdk-1.5 atom. This patch removes the >=virtual/jdk-1.5
atom from the _expand_new_virtuals output, in order to avoid triggering
the erroneous dep_zapdeps behavior. The >=virtual/jdk-1.5 atom is not
completely discarded, since the depgraph is able to access it via the
virt_atom._orig_atom attribute.

In order to demonstrate that this patch solves the problem, run the
command `emerge ant-core` from inside a stage3 chroot, and see that
virtual/jdk:1.8 is favored over virtual/jdk:1.7.

X-Gentoo-Bug: 597752
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=597752
Acked-by: Brian Dolbec <dolsen <AT> gentoo.org>

 pym/_emerge/depgraph.py      |  6 +++++-
 pym/portage/dep/dep_check.py | 13 +++++++------
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index 26037ad..9161914 100644
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -4453,7 +4453,11 @@ class depgraph(object):
 				# _UNREACHABLE_DEPTH for complete mode.
 				virt_depth = parent.depth
 
-			chosen_atom_ids = frozenset(id(atom) for atom in mycheck[1])
+			chosen_atom_ids = frozenset(chain(
+				(id(atom) for atom in mycheck[1]),
+				(id(atom._orig_atom) for atom in mycheck[1]
+					if hasattr(atom, '_orig_atom')),
+			))
 			selected_atoms = OrderedDict()
 			node_stack = [(parent, None, None)]
 			traversed_nodes = set()

diff --git a/pym/portage/dep/dep_check.py b/pym/portage/dep/dep_check.py
index 9af4e65..9d2ca4b 100644
--- a/pym/portage/dep/dep_check.py
+++ b/pym/portage/dep/dep_check.py
@@ -188,13 +188,14 @@ def _expand_new_virtuals(mysplit, edebug, mydbapi, mysettings, myroot="/",
 				raise ParseError("%s: %s '%s'" % \
 					(pkg, mycheck[1], depstring))
 
-			# Pull in virt_atom which refers to the specific version
-			# of the virtual whose deps we're expanding. Also pull
-			# in the original input atom, so that callers can reliably
-			# check to see if a given input atom has been selected,
-			# as in depgraph._slot_operator_update_probe.
+			# Replace the original atom "x" with "virt_atom" which refers
+			# to the specific version of the virtual whose deps we're
+			# expanding. The virt_atom._orig_atom attribute is used
+			# by depgraph to map virt_atom back to the original atom.
+			# We specifically exclude the original atom "x" from the
+			# the expanded output here, since otherwise it could trigger
+			# incorrect dep_zapdeps behavior (see bug #597752).
 			mycheck[1].append(virt_atom)
-			mycheck[1].append(x)
 			a.append(mycheck[1])
 			if atom_graph is not None:
 				virt_atom_node = (virt_atom, id(virt_atom))