+test_begin_subtest "notmuch-search-show-thread returns non-nil on success"
+test_emacs_expect_t '(notmuch-search "id:20091117203301.GV3165@dottiness.seas.harvard.edu")
+ (notmuch-test-wait)
+ (and (notmuch-search-show-thread)
+ (not (notmuch-show-next-thread)))'
+
+test_begin_subtest "notmuch-search-show-thread returns nil when there are no messages"
+test_emacs_expect_t '(notmuch-search "id:non-existing-id")
+ (notmuch-test-wait)
+ (not (notmuch-search-show-thread))'
+