Fix: (org-ql-completing-read) Warn about empty headings

README.org

@@ -549,6 +549,7 @@ Simple links may also be written manually in either sexp or non-sexp form, like:
 + Query parser ignores leading whitespace (e.g. preventing errors while the user is typing a query into ~org-ql-find~).
 + Use of ~org-ql-find~ with ~:query-prefix~ argument prevented selection of results.  ([[https://github.com/alphapapa/org-ql/issues/351][#351]].  Thanks to [[https://github.com/danielfleischer][Daniel Fleischer]] for reporting.)
 + Handle narrowed buffers correctly in ~org-ql-find~.
++ Warn about empty headings in ~org-ql-completing-read~ (the Org format allows a heading line to have no text, but it's useless for this purpose, and usually indicates unnoticed corruption).
 
 ** 0.7.1
 

org-ql-completing-read.el

@@ -117,6 +117,12 @@ single predicate)."
                   ;; optional arguments in a certain Org version, so in those versions, it will
                   ;; return priority cookies and comment strings.
                   (let ((heading (org-link-display-format (org-entry-get (point) "ITEM"))))
+                    (if (string-empty-p heading)
+                        ;; A heading's string can be empty, but we can't use one because it
+                        ;; wouldn't be useful to the user; and if one is found, it's very
+                        ;; likely to indicate an unnoticed mistake or corruption in the
+                        ;; file: so display a warning and don't record it as a candidate.
+                        (warn "Empty heading at %S in %S" (point) (buffer-name))
                       (when (gethash heading table)
                         ;; Disambiguate heading (even adding the path isn't enough, because that could
                         ;; also be duplicated).
@@ -124,7 +130,7 @@ single predicate)."
                             (setf heading (format "%s <%s>" heading (cl-incf suffix)))
                           (setf heading (format "%s <%s>" heading (puthash heading 2 disambiguations)))))
                       (let ((marker (point-marker)))
-                      (puthash (propertize heading 'org-marker marker) marker table))))
+                        (puthash (propertize heading 'org-marker marker) marker table)))))
                 (path (marker)
                   (org-with-point-at marker
                     (let* ((path (thread-first (org-get-outline-path nil t)

org-ql.info

@@ -1038,6 +1038,9 @@ File: README.info,  Node: 072-pre,  Next: 071,  Up: Changelog
      (https://github.com/alphapapa/org-ql/issues/351).  Thanks to Daniel
      Fleischer (https://github.com/danielfleischer) for reporting.)
    • Handle narrowed buffers correctly in ‘org-ql-find’.
+   • Warn about empty headings in ‘org-ql-completing-read’ (the Org
+     format allows a heading line to have no text, but it’s useless for
+     this purpose, and usually indicates unnoticed corruption).
 
 
 File: README.info,  Node: 071,  Next: 07,  Prev: 072-pre,  Up: Changelog
@@ -1779,37 +1782,37 @@ Node: Links37257
 Node: Tips37944
 Node: Changelog38268
 Node: 072-pre39053
-Node: 07139760
-Node: 0740573
-Node: 06343497
-Node: 06244028
-Node: 06144333
-Node: 0644901
-Node: 05247955
-Node: 05148255
-Node: 0548678
-Node: 04950209
-Node: 04850491
-Node: 04750840
-Node: 04651249
-Node: 04551657
-Node: 04452018
-Node: 04352377
-Node: 04252580
-Node: 04152741
-Node: 0452988
-Node: 03257089
-Node: 03157492
-Node: 0357689
-Node: 02360989
-Node: 02261223
-Node: 02161503
-Node: 0261708
-Node: 0165786
-Node: Notes65887
-Node: Comparison with Org Agenda searches66049
-Node: org-sidebar66938
-Node: License67217
+Node: 07139972
+Node: 0740785
+Node: 06343709
+Node: 06244240
+Node: 06144545
+Node: 0645113
+Node: 05248167
+Node: 05148467
+Node: 0548890
+Node: 04950421
+Node: 04850703
+Node: 04751052
+Node: 04651461
+Node: 04551869
+Node: 04452230
+Node: 04352589
+Node: 04252792
+Node: 04152953
+Node: 0453200
+Node: 03257301
+Node: 03157704
+Node: 0357901
+Node: 02361201
+Node: 02261435
+Node: 02161715
+Node: 0261920
+Node: 0165998
+Node: Notes66099
+Node: Comparison with Org Agenda searches66261
+Node: org-sidebar67150
+Node: License67429
 
 End Tag Table