1 files changed, 81 insertions, 0 deletions
diff --git a/t/t2022-checkout-paths.sh b/t/t2022-checkout-paths.sh
new file mode 100755
index 000000000000..fc3eb43b8909
--- /dev/null
+++ b/t/t2022-checkout-paths.sh
@@ -0,0 +1,81 @@
+#!/bin/sh
+
+test_description='checkout $tree -- $paths'
+. ./test-lib.sh
+
+test_expect_success setup '
+	mkdir dir &&
+	>dir/master &&
+	echo common >dir/common &&
+	git add dir/master dir/common &&
+	test_tick && git commit -m "master has dir/master" &&
+	git checkout -b next &&
+	git mv dir/master dir/next0 &&
+	echo next >dir/next1 &&
+	git add dir &&
+	test_tick && git commit -m "next has dir/next but not dir/master"
+'
+
+test_expect_success 'checking out paths out of a tree does not clobber unrelated paths' '
+	git checkout next &&
+	git reset --hard &&
+	rm dir/next0 &&
+	cat dir/common >expect.common &&
+	echo modified >expect.next1 &&
+	cat expect.next1 >dir/next1 &&
+	echo untracked >expect.next2 &&
+	cat expect.next2 >dir/next2 &&
+
+	git checkout master dir &&
+
+	test_cmp expect.common dir/common &&
+	test_path_is_file dir/master &&
+	git diff --exit-code master dir/master &&
+
+	test_path_is_missing dir/next0 &&
+	test_cmp expect.next1 dir/next1 &&
+	test_path_is_file dir/next2 &&
+	test_must_fail git ls-files --error-unmatch dir/next2 &&
+	test_cmp expect.next2 dir/next2
+'
+
+test_expect_success 'do not touch unmerged entries matching $path but not in $tree' '
+	git checkout next &&
+	git reset --hard &&
+
+	cat dir/common >expect.common &&
+	EMPTY_SHA1=$(git hash-object -w --stdin </dev/null) &&
+	git rm dir/next0 &&
+	cat >expect.next0 <<-EOF &&
+	100644 $EMPTY_SHA1 1	dir/next0
+	100644 $EMPTY_SHA1 2	dir/next0
+	EOF
+	git update-index --index-info <expect.next0 &&
+
+	git checkout master dir &&
+
+	test_cmp expect.common dir/common &&
+	test_path_is_file dir/master &&
+	git diff --exit-code master dir/master &&
+	git ls-files -s dir/next0 >actual.next0 &&
+	test_cmp expect.next0 actual.next0
+'
+
+test_expect_success 'do not touch files that are already up-to-date' '
+	git reset --hard &&
+	echo one >file1 &&
+	echo two >file2 &&
+	git add file1 file2 &&
+	git commit -m base &&
+	echo modified >file1 &&
+	test-tool chmtime =1000000000 file2 &&
+	git update-index -q --refresh &&
+	git checkout HEAD -- file1 file2 &&
+	echo one >expect &&
+	test_cmp expect file1 &&
+	echo "1000000000" >expect &&
+	test-tool chmtime --get file2 >actual &&
+	test_cmp expect actual
+'
+
+test_done