test: use (format "%S") to print nil in emacs test.

[notmuch] / test / emacs-subject-to-filename

diff --git a/test/emacs-subject-to-filename b/test/emacs-subject-to-filename
index 176e6859b0dbaba87d13f9bf87121eb49e469a83..a0ffdfef038aefcea46acd12f7d6e765e9c39d5a 100755 (executable)
--- a/test/emacs-subject-to-filename
+++ b/test/emacs-subject-to-filename
@@ -8,10 +8,10 @@ test_emacs '(ignore)'
 
 # test notmuch-wash-subject-to-patch-sequence-number (subject)
 test_begin_subtest "no patch sequence number"
-output=$(test_emacs '(notmuch-wash-subject-to-patch-sequence-number
-      "[PATCH] A normal patch subject without numbers")'
+output=$(test_emacs '(format "%S" (notmuch-wash-subject-to-patch-sequence-number
+      "[PATCH] A normal patch subject without numbers"))'
 )
-test_expect_equal "$output" ""
+test_expect_equal "$output" '"nil"'
 
 test_begin_subtest "patch sequence number #1"
 output=$(test_emacs '(notmuch-wash-subject-to-patch-sequence-number