1 files changed, 277 insertions, 0 deletions
diff --git a/t/t2501-cwd-empty.sh b/t/t2501-cwd-empty.sh
new file mode 100755
index 0000000000..f6d8d7d03d
--- /dev/null
+++ b/t/t2501-cwd-empty.sh
@@ -0,0 +1,277 @@
+#!/bin/sh
+
+test_description='Test handling of the current working directory becoming empty'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	test_commit init &&
+
+	git branch fd_conflict &&
+
+	mkdir -p foo/bar &&
+	test_commit foo/bar/baz &&
+
+	git revert HEAD &&
+	git tag reverted &&
+
+	git checkout fd_conflict &&
+	mkdir dirORfile &&
+	test_commit dirORfile/foo &&
+
+	git rm -r dirORfile &&
+	echo not-a-directory >dirORfile &&
+	git add dirORfile &&
+	git commit -m dirORfile &&
+
+	git switch -c df_conflict HEAD~1 &&
+	test_commit random_file &&
+
+	git switch -c undo_fd_conflict fd_conflict &&
+	git revert HEAD
+'
+
+test_incidental_dir_removal () {
+	test_when_finished "git reset --hard" &&
+
+	git checkout foo/bar/baz^{commit} &&
+	test_path_is_dir foo/bar &&
+
+	(
+		cd foo &&
+		"$@" &&
+
+		# Make sure foo still exists, and commands needing it work
+		test-tool getcwd &&
+		git status --porcelain
+	) &&
+	test_path_is_missing foo/bar/baz &&
+	test_path_is_missing foo/bar &&
+
+	test_path_is_dir foo
+}
+
+test_required_dir_removal () {
+	git checkout df_conflict^{commit} &&
+	test_when_finished "git clean -fdx" &&
+
+	(
+		cd dirORfile &&
+
+		# Ensure command refuses to run
+		test_must_fail "$@" 2>../error &&
+		grep "Refusing to remove.*current working directory" ../error &&
+
+		# ...and that the index and working tree are left clean
+		git diff --exit-code HEAD &&
+
+		# Ensure that getcwd and git status do not error out (which
+		# they might if the current working directory had been removed)
+		test-tool getcwd &&
+		git status --porcelain
+	) &&
+
+	test_path_is_dir dirORfile
+}
+
+test_expect_success 'checkout does not clean cwd incidentally' '
+	test_incidental_dir_removal git checkout init
+'
+
+test_expect_success 'checkout fails if cwd needs to be removed' '
+	test_required_dir_removal git checkout fd_conflict
+'
+
+test_expect_success 'reset --hard does not clean cwd incidentally' '
+	test_incidental_dir_removal git reset --hard init
+'
+
+test_expect_success 'reset --hard fails if cwd needs to be removed' '
+	test_required_dir_removal git reset --hard fd_conflict
+'
+
+test_expect_success 'merge does not clean cwd incidentally' '
+	test_incidental_dir_removal git merge reverted
+'
+
+# This file uses some simple merges where
+#   Base: 'dirORfile/' exists
+#   Side1: random other file changed
+#   Side2: 'dirORfile/' removed, 'dirORfile' added
+# this should resolve cleanly, but merge-recursive throws merge conflicts
+# because it's dumb.  Add a special test for checking merge-recursive (and
+# merge-ort), then after this just hard require ort for all remaining tests.
+#
+test_expect_success 'merge fails if cwd needs to be removed; recursive friendly' '
+	git checkout foo/bar/baz &&
+	test_when_finished "git clean -fdx" &&
+
+	mkdir dirORfile &&
+	(
+		cd dirORfile &&
+
+		test_must_fail git merge fd_conflict 2>../error
+	) &&
+
+	test_path_is_dir dirORfile &&
+	grep "Refusing to remove the current working directory" error
+'
+
+GIT_TEST_MERGE_ALGORITHM=ort
+
+test_expect_success 'merge fails if cwd needs to be removed' '
+	test_required_dir_removal git merge fd_conflict
+'
+
+test_expect_success 'cherry-pick does not clean cwd incidentally' '
+	test_incidental_dir_removal git cherry-pick reverted
+'
+
+test_expect_success 'cherry-pick fails if cwd needs to be removed' '
+	test_required_dir_removal git cherry-pick fd_conflict
+'
+
+test_expect_success 'rebase does not clean cwd incidentally' '
+	test_incidental_dir_removal git rebase reverted
+'
+
+test_expect_success 'rebase fails if cwd needs to be removed' '
+	test_required_dir_removal git rebase fd_conflict
+'
+
+test_expect_success 'revert does not clean cwd incidentally' '
+	test_incidental_dir_removal git revert HEAD
+'
+
+test_expect_success 'revert fails if cwd needs to be removed' '
+	test_required_dir_removal git revert undo_fd_conflict
+'
+
+test_expect_success 'rm does not clean cwd incidentally' '
+	test_incidental_dir_removal git rm bar/baz.t
+'
+
+test_expect_success 'apply does not remove cwd incidentally' '
+	git diff HEAD HEAD~1 >patch &&
+	test_incidental_dir_removal git apply ../patch
+'
+
+test_incidental_untracked_dir_removal () {
+	test_when_finished "git reset --hard" &&
+
+	git checkout foo/bar/baz^{commit} &&
+	mkdir -p untracked &&
+	mkdir empty
+	>untracked/random &&
+
+	(
+		cd untracked &&
+		"$@" &&
+
+		# Make sure untracked still exists, and commands needing it work
+		test-tool getcwd &&
+		git status --porcelain
+	) &&
+	test_path_is_missing empty &&
+	test_path_is_missing untracked/random &&
+
+	test_path_is_dir untracked
+}
+
+test_expect_success 'clean does not remove cwd incidentally' '
+	test_incidental_untracked_dir_removal \
+		git -C .. clean -fd -e warnings . >warnings &&
+	grep "Refusing to remove current working directory" warnings
+'
+
+test_expect_success 'stash does not remove cwd incidentally' '
+	test_incidental_untracked_dir_removal \
+		git stash --include-untracked
+'
+
+test_expect_success '`rm -rf dir` only removes a subset of dir' '
+	test_when_finished "rm -rf a/" &&
+
+	mkdir -p a/b/c &&
+	>a/b/c/untracked &&
+	>a/b/c/tracked &&
+	git add a/b/c/tracked &&
+
+	(
+		cd a/b &&
+		git rm -rf ../b
+	) &&
+
+	test_path_is_dir a/b &&
+	test_path_is_missing a/b/c/tracked &&
+	test_path_is_file a/b/c/untracked
+'
+
+test_expect_success '`rm -rf dir` even with only tracked files will remove something else' '
+	test_when_finished "rm -rf a/" &&
+
+	mkdir -p a/b/c &&
+	>a/b/c/tracked &&
+	git add a/b/c/tracked &&
+
+	(
+		cd a/b &&
+		git rm -rf ../b
+	) &&
+
+	test_path_is_missing a/b/c/tracked &&
+	test_path_is_missing a/b/c &&
+	test_path_is_dir a/b
+'
+
+test_expect_success 'git version continues working from a deleted dir' '
+	mkdir tmp &&
+	(
+		cd tmp &&
+		rm -rf ../tmp &&
+		git version
+	)
+'
+
+test_submodule_removal () {
+	path_status=$1 &&
+	shift &&
+
+	test_status=
+	test "$path_status" = dir && test_status=test_must_fail
+
+	test_when_finished "git reset --hard HEAD~1" &&
+	test_when_finished "rm -rf .git/modules/my_submodule" &&
+
+	git checkout foo/bar/baz &&
+
+	git init my_submodule &&
+	touch my_submodule/file &&
+	git -C my_submodule add file &&
+	git -C my_submodule commit -m "initial commit" &&
+	git submodule add ./my_submodule &&
+	git commit -m "Add the submodule" &&
+
+	(
+		cd my_submodule &&
+		$test_status "$@"
+	) &&
+
+	test_path_is_${path_status} my_submodule
+}
+
+test_expect_success 'rm -r with -C leaves submodule if cwd inside' '
+	test_submodule_removal dir git -C .. rm -r my_submodule/
+'
+
+test_expect_success 'rm -r leaves submodule if cwd inside' '
+	test_submodule_removal dir \
+		git --git-dir=../.git --work-tree=.. rm -r ../my_submodule/
+'
+
+test_expect_success 'rm -rf removes submodule even if cwd inside' '
+	test_submodule_removal missing \
+		git --git-dir=../.git --work-tree=.. rm -rf ../my_submodule/
+'
+
+test_done