diff --git a/t/test-lib.sh b/t/test-lib.sh
index 9e2b71132a..32a74a6e7a 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -15,6 +15,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see http://www.gnu.org/licenses/ .
 
+# for git on windows so stdin will not be misdetected as attached to a
+# terminal
+exec < /dev/null
+
 # if --tee was passed, write the output not only to the terminal, but
 # additionally to the file test-results/$BASENAME.out, too.
 case "$GIT_TEST_TEE_STARTED, $* " in