fix(agenda): hide the refresh tick's selection flicker

The rebuild takes a second or two, and for its whole duration the agenda window was the selected window, so the cursor visibly went hollow in the working frame on every tick. It read as focus theft, though no focus function ever ran. The tick now inhibits redisplay (the synchronous rebuild blocks Emacs anyway, so this costs nothing) and restores selection before redisplay resumes. A tick that would fire during an active minibuffer is skipped.

2 files changed, 46 insertions, 2 deletions

diff --git a/modules/org-agenda-frame.el b/modules/org-agenda-frame.el
index fd911a97..2604f979 100644
--- a/modules/org-agenda-frame.el
+++ b/modules/org-agenda-frame.el
@@ -658,8 +658,20 @@ out-of-range window-start nor steals focus."
          (buffer (cj/--agenda-frame-sticky-buffer))
          (window (and (frame-live-p frame) (buffer-live-p buffer)
                       (get-buffer-window buffer frame))))
-    (when (window-live-p window)
-      (let ((prev-window (selected-window)))
+    (when (and (window-live-p window)
+               ;; Skip the tick while a minibuffer is active anywhere --
+               ;; reselecting windows under an active minibuffer session can
+               ;; break it, and the next tick catches up.
+               (not (active-minibuffer-window)))
+      (let ((prev-window (selected-window))
+            ;; The rebuild takes visible time, and for its duration the
+            ;; agenda window is the selected window.  Without inhibiting
+            ;; redisplay the user's cursor visibly goes hollow for the whole
+            ;; rebuild every tick -- indistinguishable from focus theft.
+            ;; The rebuild blocks Emacs either way (it is synchronous), so
+            ;; this hides the selection flicker at no extra cost; redisplay
+            ;; resumes after the selection is restored.
+            (inhibit-redisplay t))
         (unwind-protect
             (progn
               (select-window window t)
diff --git a/tests/test-org-agenda-frame.el b/tests/test-org-agenda-frame.el
index 29b6a36f..972df6ec 100644
--- a/tests/test-org-agenda-frame.el
+++ b/tests/test-org-agenda-frame.el
@@ -875,6 +875,38 @@ showing the launch buffer."
       (should (eq (cj/--agenda-frame-spawn) 'af))
       (should (eq timed 'af)))))
 
+(ert-deftest test-org-agenda-frame-safe-redo-inhibits-redisplay ()
+  "Normal: the tick runs with redisplay inhibited.
+The rebuild takes visible time; without this, the agenda window is the
+selected window for the whole rebuild and the user watches their cursor
+go hollow every five minutes -- indistinguishable from focus theft."
+  (let (seen (prev (selected-window)))
+    (cl-letf (((symbol-function 'cj/--agenda-frame) (lambda () 'af))
+              ((symbol-function 'cj/--agenda-frame-sticky-buffer)
+               (lambda () (current-buffer)))
+              ((symbol-function 'frame-live-p) (lambda (_f) t))
+              ((symbol-function 'get-buffer-window) (lambda (&rest _) prev))
+              ((symbol-function 'cj/--agenda-frame-do-redo)
+               (lambda (&rest _) (setq seen inhibit-redisplay))))
+      (cj/--agenda-frame-safe-redo)
+      (should (eq seen t)))))
+
+(ert-deftest test-org-agenda-frame-safe-redo-skips-during-minibuffer ()
+  "Boundary: a tick while a minibuffer is active is skipped entirely.
+Reselecting windows under an active minibuffer session can break it; the
+next tick catches up."
+  (let (redone (prev (selected-window)))
+    (cl-letf (((symbol-function 'active-minibuffer-window) (lambda () 'mini))
+              ((symbol-function 'cj/--agenda-frame) (lambda () 'af))
+              ((symbol-function 'cj/--agenda-frame-sticky-buffer)
+               (lambda () (current-buffer)))
+              ((symbol-function 'frame-live-p) (lambda (_f) t))
+              ((symbol-function 'get-buffer-window) (lambda (&rest _) prev))
+              ((symbol-function 'cj/--agenda-frame-do-redo)
+               (lambda (&rest _) (setq redone t))))
+      (cj/--agenda-frame-safe-redo)
+      (should-not redone))))
+
 (ert-deftest test-org-agenda-frame-safe-redo-noop-when-not-shown ()
   "Boundary: a tick with the buffer not shown in the frame does not redo or error."
   (let (redone)