1 files changed, 51 insertions, 0 deletions
diff --git a/lib/portage/tests/resolver/test_unnecessary_slot_upgrade.py b/lib/portage/tests/resolver/test_unnecessary_slot_upgrade.py
new file mode 100644
index 000000000..a89ebdb67
--- /dev/null
+++ b/lib/portage/tests/resolver/test_unnecessary_slot_upgrade.py
@@ -0,0 +1,51 @@
+# Copyright 2021 Gentoo Authors
+# 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 UnnecessarySlotrUpgradeTestCase(TestCase):
+    def testUnnecessarySlotUpgrade(self):
+        ebuilds = {
+            "app-misc/a-1": {
+                "EAPI": "8",
+                "RDEPEND": "|| ( dev-lang/python:3.10 dev-lang/python:3.9 ) || ( dev-lang/python:3.10 dev-lang/python:3.9 )",
+            },
+            "dev-lang/python-3.9": {"SLOT": "3.9"},
+            "dev-lang/python-3.10": {"SLOT": "3.10"},
+        }
+
+        installed = {
+            "dev-lang/python-3.9": {"SLOT": "3.9"},
+        }
+
+        test_cases = (
+            # Test bug 828136, where an unnecessary python slot upgrade
+            # was triggered.
+            ResolverPlaygroundTestCase(
+                [
+                    "app-misc/a",
+                ],
+                success=True,
+                mergelist=(
+                    "dev-lang/python-3.10",
+                    "app-misc/a-1",
+                ),
+            ),
+        )
+
+        playground = ResolverPlayground(
+            debug=False, ebuilds=ebuilds, installed=installed
+        )
+
+        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.debug = False
+            playground.cleanup()