org-node-cache-mode warns "No files found" about a scan that is still running

[myshevchuk]

org-node-cache-mode ends with:

(org-mem-reset)
(org-mem-tip-if-empty)

org-mem-reset starts an asynchronous scan, and org-mem-tip-if-empty is then
asked whether the cache is empty — which, on a cold start, it always is at that
instant. So enabling the mode reliably prints a warning about a scan that goes
on to succeed.

org-node-cache-ensure does not have this problem: it awaits first, then tips.

MWE

emacs -Q --batch, with org-mem and org-node on load-path:

(require 'org-mem)
(require 'org-node)

;; A directory holding one file with one ID.
(setq org-mem-watch-dirs '("/tmp/orgmemmwe/"))

(message "--- enabling modes ---")
(org-mem-updater-mode)
(org-node-cache-mode)
(message "--- awaiting scan ---")
(org-mem-await "" 30)
(message "after scan: %d files, %d id-nodes"
         (length (org-mem-all-files)) (length (org-mem-all-id-nodes)))

Output:

--- enabling modes ---
org-mem: No files found in ‘org-mem-watch-dirs’, and no org-ids because Org not loaded
--- awaiting scan ---
after scan: 1 files, 1 id-nodes

How visible it is

It depends on whether org-mem's scan has landed by the time org-node-cache-mode
runs. With the two use-package blocks from the manual, whatever else init does
in between often covers the gap. I defer both to a single hook (Doom's
doom-first-input-hook), so they load back to back and the message appears every
session — over ~430 files the scan takes about 2 s.

Suggested fix

Ask the question where it can be answered — from
org-mem-post-full-scan-functions, one-shot — so the tip reports a cache that is
still empty after the scan meant to fill it. Locally I do:

(defun my-tip-when-settled (&rest _)
  (remove-hook 'org-mem-post-full-scan-functions #'my-tip-when-settled)
  (org-mem-tip-if-empty))

(cl-letf (((symbol-function 'org-mem-tip-if-empty) #'ignore))
  (org-node-cache-mode))
(add-hook 'org-mem-post-full-scan-functions #'my-tip-when-settled)

which keeps the diagnostic for a genuinely empty cache and drops the false alarm.

Versions: org-node 10ea878, org-mem 07094da, Emacs 30.2.

_{Investigated with Claude Code; the MWE output above is from a real run.}