+test_begin_subtest "dump message properties"
+cat <<EOF > PROPERTIES
+#= 4EFC743A.3060609@april.org fancy%20key%20with%20%c3%a1cc%c3%a8nts=import%20value%20with%20= testkey1=alice testkey1=bob testkey1=testvalue1 testkey1=testvalue2 testkey3=alice3 testkey3=bob3 testkey3=testvalue3
+EOF
+cat c_head - c_tail <<'EOF' | test_C ${MAIL_DIR}
+EXPECT0(notmuch_message_add_property (message, "fancy key with áccènts", "import value with ="));
+EOF
+notmuch dump | grep '^#=' > OUTPUT
+test_expect_equal_file PROPERTIES OUTPUT
+