Add a rename + D/F conflict testcase

This is a simple testcase where both sides of the rename are paths involved
in (separate) D/F merge conflicts

Signed-off-by: Alexander Gladysh <agladysh@gmail.com>
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t3509-cherry-pick-merge-df.sh

@@ -0,0 +1,35 @@
+#!/bin/sh
+
+test_description='Test cherry-pick with directory/file conflicts'
+. ./test-lib.sh
+
+test_expect_success 'Setup rename across paths each below D/F conflicts' '
+	mkdir a &&
+	>a/f &&
+	git add a &&
+	git commit -m a &&
+
+	mkdir b &&
+	ln -s ../a b/a &&
+	git add b &&
+	git commit -m b &&
+
+	git checkout -b branch &&
+	rm b/a &&
+	mv a b/a &&
+	ln -s b/a a &&
+	git add . &&
+	git commit -m swap &&
+
+	>f1 &&
+	git add f1 &&
+	git commit -m f1
+'
+
+test_expect_failure 'Cherry-pick succeeds with rename across D/F conflicts' '
+	git reset --hard &&
+	git checkout master^0 &&
+	git cherry-pick branch
+'
+
+test_done