Fix exiting from editing todo archive file (bug#32437)

* lisp/calendar/todo-mode.el (todo-edit-file): Make the warning
also suitable for Todo Archive mode, and add more space to it.
(todo-edit-quit): On quitting editing an archive file, return to
the Todo Archive mode buffer editing was invoked in.
(todo-check-format): Display a warning instead of a message when
the categories sexp isn't as expected.
(todo-mode-external-set): Remove.
(todo-edit-mode): Set buffer local values of
todo-current-todo-file and todo-categories from the todo or
archive file being edited.
(todo-categories-mode): Set buffer local values of
todo-current-todo-file and todo-categories as before but directly
instead of using superfluous todo-mode-external-set function.

* test/lisp/calendar/todo-mode-tests.el (todo-test-edit-quit): New test.

1 files changed, 18 insertions, 0 deletions

diff --git a/test/lisp/calendar/todo-mode-tests.el b/test/lisp/calendar/todo-mode-tests.el
index 325faeff514..90282045062 100644
--- a/test/lisp/calendar/todo-mode-tests.el
+++ b/test/lisp/calendar/todo-mode-tests.el
@@ -763,6 +763,24 @@ The highlighting should remain enabled."
    (ert-simulate-command '(forward-line)) ; Now on first done item.
    (should (eq 'hl-line (get-char-property (point) 'face)))))
 
+(ert-deftest todo-test-edit-quit ()
+  "Test result of exiting todo-edit-mode on a whole file.
+Exiting should return to the same todo-mode or todo-archive-mode
+buffer from which the editing command was invoked."
+  (with-todo-test
+   (todo-test--show 1)
+   (let ((buf (current-buffer)))
+     (todo-edit-file)
+     (todo-edit-quit)
+     (should (eq (current-buffer) buf))
+     (should (eq major-mode 'todo-mode))
+   (todo-find-archive)
+   (let ((buf (current-buffer)))
+     (todo-edit-file)
+     (todo-edit-quit)
+     (should (eq (current-buffer) buf))
+     (should (eq major-mode 'todo-archive-mode))))))
+
 
 (provide 'todo-mode-tests)
 ;;; todo-mode-tests.el ends here