Merge branch 'js/checkout-untracked-symlink' into maint

* js/checkout-untracked-symlink:
  do not overwrite untracked symlinks
  Demonstrate breakage: checkout overwrites untracked symlink with directory

2 files changed, 61 insertions, 3 deletions

diff --git a/t/t2021-checkout-overwrite.sh b/t/t2021-checkout-overwrite.sh
new file mode 100755
index 0000000000..27db2ad529
--- /dev/null
+++ b/t/t2021-checkout-overwrite.sh
@@ -0,0 +1,50 @@
+#!/bin/sh
+
+test_description='checkout must not overwrite an untracked objects'
+. ./test-lib.sh
+
+test_expect_success 'setup' '
+
+	mkdir -p a/b/c &&
+	>a/b/c/d &&
+	git add -A &&
+	git commit -m base &&
+	git tag start
+'
+
+test_expect_success 'create a commit where dir a/b changed to file' '
+
+	git checkout -b file &&
+	rm -rf a/b &&
+	>a/b &&
+	git add -A &&
+	git commit -m "dir to file"
+'
+
+test_expect_success 'checkout commit with dir must not remove untracked a/b' '
+
+	git rm --cached a/b &&
+	git commit -m "un-track the file" &&
+	test_must_fail git checkout start &&
+	test -f a/b
+'
+
+test_expect_success SYMLINKS 'create a commit where dir a/b changed to symlink' '
+
+	rm -rf a/b &&	# cleanup if previous test failed
+	git checkout -f -b symlink start &&
+	rm -rf a/b &&
+	ln -s foo a/b &&
+	git add -A &&
+	git commit -m "dir to symlink"
+'
+
+test_expect_failure SYMLINKS 'checkout commit with dir must not remove untracked a/b' '
+
+	git rm --cached a/b &&
+	git commit -m "un-track the symlink" &&
+	test_must_fail git checkout start &&
+	test -h a/b
+'
+
+test_done
diff --git a/t/t6035-merge-dir-to-symlink.sh b/t/t6035-merge-dir-to-symlink.sh
index 92e02d5d77..2599ae50eb 100755
--- a/t/t6035-merge-dir-to-symlink.sh
+++ b/t/t6035-merge-dir-to-symlink.sh
@@ -17,13 +17,21 @@ test_expect_success SYMLINKS 'create a commit where dir a/b changed to symlink'
 	git commit -m "dir to symlink"
 '
 
-test_expect_success SYMLINKS 'keep a/b-2/c/d across checkout' '
+test_expect_success SYMLINKS 'checkout does not clobber untracked symlink' '
 	git checkout HEAD^0 &&
 	git reset --hard master &&
 	git rm --cached a/b &&
 	git commit -m "untracked symlink remains" &&
-	 git checkout start^0 &&
-	 test -f a/b-2/c/d
+	test_must_fail git checkout start^0
+'
+
+test_expect_success SYMLINKS 'a/b-2/c/d is kept when clobbering symlink b' '
+	git checkout HEAD^0 &&
+	git reset --hard master &&
+	git rm --cached a/b &&
+	git commit -m "untracked symlink remains" &&
+	git checkout -f start^0 &&
+	test -f a/b-2/c/d
 '
 
 test_expect_success SYMLINKS 'checkout should not have deleted a/b-2/c/d' '