t6022: Add testcase for merging a renamed file with a simple change

This is a testcase that was broken by b2c8c0a (merge-recursive: When we
detect we can skip an update, actually skip it 2011-02-28) and fixed by
6db4105 (Revert "Merge branch 'en/merge-recursive'" 2011-05-19).  Include
this testcase to ensure we don't regress it again.

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

t/t6022-merge-rename.sh

@@ -673,4 +673,31 @@ test_expect_failure 'avoid unnecessary update, with D/F conflict' '
 	test_cmp expect actual # "df" should have stayed intact
 '
 
+test_expect_success 'setup merge of rename + small change' '
+	git reset --hard &&
+	git checkout --orphan rename-plus-small-change &&
+	git rm -rf . &&
+	git clean -fdqx &&
+
+	echo ORIGINAL >file &&
+	git add file &&
+
+	test_tick &&
+	git commit -m Initial &&
+	git checkout -b rename_branch &&
+	git mv file renamed_file &&
+	git commit -m Rename &&
+	git checkout rename-plus-small-change &&
+	echo NEW-VERSION >file &&
+	git commit -a -m Reformat
+'
+
+test_expect_success 'merge rename + small change' '
+	git merge rename_branch &&
+
+	test 1 -eq $(git ls-files -s | wc -l) &&
+	test 0 -eq $(git ls-files -o | wc -l) &&
+	test $(git rev-parse HEAD:renamed_file) = $(git rev-parse HEAD~1:file)
+'
+
 test_done