From: Zac Medico <zmedico@gentoo.org>
Date: Sun, 12 Jun 2011 22:12:26 +0000 (-0700)
Subject: test_merge_order: test smallest runtime cycle
X-Git-Tag: v2.2.0_alpha41~5
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=c754569663408e515fa134c52c7b3b8a1bb15181;p=portage.git

test_merge_order: test smallest runtime cycle

In the case of multiple runtime cycles, where some cycles
may depend on smaller independent cycles, it's optimal
to merge smaller independent cycles before other cycles
that depend on them. Therefore, we search for the
smallest cycle in order to try and identify and prefer
these smaller independent cycles.
---

diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index 3b47c3574..9ce199b15 100644
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -5022,6 +5022,12 @@ class depgraph(object):
 					# we want to minimize the number of nodes gathered, since
 					# this tends to produce a more optimal merge order.
 					# Ignoring all medium_soft deps serves this purpose.
+					# In the case of multiple runtime cycles, where some cycles
+					# may depend on smaller independent cycles, it's optimal
+					# to merge smaller independent cycles before other cycles
+					# that depend on them. Therefore, we search for the
+					# smallest cycle in order to try and identify and prefer
+					# these smaller independent cycles.
 					ignore_priority = priority_range.ignore_medium_soft
 					smallest_cycle = None
 					for node in nodes:
diff --git a/pym/portage/tests/resolver/test_merge_order.py b/pym/portage/tests/resolver/test_merge_order.py
index e94b6c7dd..0a52c813b 100644
--- a/pym/portage/tests/resolver/test_merge_order.py
+++ b/pym/portage/tests/resolver/test_merge_order.py
@@ -81,6 +81,27 @@ class MergeOrderTestCase(TestCase):
 				"DEPEND": "app-misc/circ-satisfied-a",
 				"RDEPEND": "app-misc/circ-satisfied-a",
 			},
+			"app-misc/circ-smallest-a-1": {
+				"RDEPEND": "app-misc/circ-smallest-b",
+			},
+			"app-misc/circ-smallest-b-1": {
+				"RDEPEND": "app-misc/circ-smallest-a",
+			},
+			"app-misc/circ-smallest-c-1": {
+				"RDEPEND": "app-misc/circ-smallest-d",
+			},
+			"app-misc/circ-smallest-d-1": {
+				"RDEPEND": "app-misc/circ-smallest-e",
+			},
+			"app-misc/circ-smallest-e-1": {
+				"RDEPEND": "app-misc/circ-smallest-c",
+			},
+			"app-misc/circ-smallest-f-1": {
+				"RDEPEND": "app-misc/circ-smallest-g app-misc/circ-smallest-a app-misc/circ-smallest-c",
+			},
+			"app-misc/circ-smallest-g-1": {
+				"RDEPEND": "app-misc/circ-smallest-f",
+			},
 			"app-misc/installed-blocker-a-1" : {
 				"EAPI"   : "2",
 				"DEPEND" : "!app-misc/blocker-buildtime-a",
@@ -294,6 +315,18 @@ class MergeOrderTestCase(TestCase):
 				ambiguous_merge_order = True,
 				merge_order_assertions = (("app-misc/circ-satisfied-a-1", "app-misc/circ-satisfied-c-1"),),
 				mergelist = [("app-misc/circ-satisfied-a-1", "app-misc/circ-satisfied-b-1", "app-misc/circ-satisfied-c-1")]),
+			# In the case of multiple runtime cycles, where some cycles
+			# may depend on smaller independent cycles, it's optimal
+			# to merge smaller independent cycles before other cycles
+			# that depend on them.
+			ResolverPlaygroundTestCase(
+				["app-misc/circ-smallest-a", "app-misc/circ-smallest-c", "app-misc/circ-smallest-f"],
+				success = True,
+				ambiguous_merge_order = True,
+				all_permutations = True,
+				mergelist = [('app-misc/circ-smallest-a-1', 'app-misc/circ-smallest-b-1'),
+				('app-misc/circ-smallest-c-1', 'app-misc/circ-smallest-d-1', 'app-misc/circ-smallest-e-1'),
+				('app-misc/circ-smallest-f-1', 'app-misc/circ-smallest-g-1')]),
 			# installed package has buildtime-only blocker
 			# that should be ignored
 			ResolverPlaygroundTestCase(