refactor: extract missing-glossary test helper

Four tests across lookup, list, find-buffer-position, and first-call-creates-file shared the same boilerplate. Each let-bound gloss-file to a randomized nonexistent path, wrapped in unwind-protect, reset the cache, and cleaned up file and buffer afterward.

Extracted as gloss-test--with-missing-glossary in testutil-gloss.el, parallel to the existing gloss-test--with-temp-glossary. The four call sites drop from 8-10 lines each to 2-3.

Tested by running the full 32-test suite. All 32 pass in 0.21 seconds.

1 files changed, 18 insertions, 0 deletions

diff --git a/tests/testutil-gloss.el b/tests/testutil-gloss.el
index b70b0ea..7510765 100644
--- a/tests/testutil-gloss.el
+++ b/tests/testutil-gloss.el
@@ -58,5 +58,23 @@ visiting buffer."
        (when (file-exists-p gloss-file)
          (delete-file gloss-file)))))
 
+(defmacro gloss-test--with-missing-glossary (&rest body)
+  "Bind `gloss-file' to a path that does not yet exist; run BODY.
+Reset the in-memory cache before BODY and after.  Clean up the file and
+any visiting buffer if BODY created them."
+  (declare (indent 0) (debug t))
+  `(let ((gloss-file (concat temporary-file-directory "gloss-missing-"
+                              (number-to-string (random 100000)) ".org")))
+     (unwind-protect
+         (progn
+           (gloss-core--cache-reset)
+           ,@body)
+       (gloss-core--cache-reset)
+       (when-let ((buf (find-buffer-visiting gloss-file)))
+         (with-current-buffer buf (set-buffer-modified-p nil))
+         (kill-buffer buf))
+       (when (file-exists-p gloss-file)
+         (delete-file gloss-file)))))
+
 (provide 'testutil-gloss)
 ;;; testutil-gloss.el ends here