1 files changed, 51 insertions, 0 deletions
diff --git a/tests/cp/thru-dangling.sh b/tests/cp/thru-dangling.sh
new file mode 100755
index 0000000..e433525
--- /dev/null
+++ b/tests/cp/thru-dangling.sh
@@ -0,0 +1,51 @@
+#!/bin/sh
+# Ensure that cp works as documented, when the destination is a dangling symlink
+
+# Copyright (C) 2007-2018 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ cp
+
+ln -s no-such dangle || framework_failure_
+echo hi > f || framework_failure_
+echo hi > exp || framework_failure_
+echo "cp: not writing through dangling symlink 'dangle'" \
+    > exp-err || framework_failure_
+
+
+# Starting with 6.9.90, this usage fails, by default:
+for opt in '' '-f'; do
+  returns_ 1 cp $opt f dangle > err 2>&1 || fail=1
+  compare exp-err err || fail=1
+  test -f no-such && fail=1
+done
+
+
+# But you can set POSIXLY_CORRECT to get the historical behavior.
+env POSIXLY_CORRECT=1 cp f dangle > out 2>&1 || fail=1
+cat no-such >> out || fail=1
+compare exp out || fail=1
+
+
+# Starting with 8.30 we treat ELOOP as existing and so
+# remove the symlink
+ln -s loop loop || framework_failure_
+cp -f f loop > err 2>&1 || fail=1
+compare /dev/null err || fail=1
+compare exp loop || fail=1
+test -f loop || fail=1
+
+Exit $fail