Fix: Handle the buffer argument properly; Restore org-overview call

org-ql.el

@@ -1016,8 +1016,15 @@ When optional argument KEEP-PREVIOUS is non-nil, highlighting and
 exposing done by a previous call to `org-occur' or `org-ql-occur'
 will be kept, to allow stacking of calls to this command."
   (interactive (list (read-minibuffer "Query: ")))
+  (unless (bufferp buffer)
+    (user-error "BUFFER should be a single buffer"))
+  (with-current-buffer buffer
     (unless keep-previous
       (org-remove-occur-highlights nil nil t))
+    (when (or (not keep-previous)       ; do not want to keep
+              (not org-occur-highlights)) ; no previous matches
+      ;; hide everything
+      (org-overview))
     ;; (push (cons regexp callback) org-occur-parameters)
     (let ((result (org-ql-select buffer query
                     :action
@@ -1033,7 +1040,7 @@ will be kept, to allow stacking of calls to this command."
         (org-hide-archived-subtrees (point-min) (point-max)))
       (run-hooks 'org-occur-hook)
       (when (called-interactively-p 'interactive)
-      (message "%d match(es) for query %s" (length result) query))))
+        (message "%d match(es) for query %s" (length result) query)))))
 
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