fix: clear stale end-pos on resume so final-report fires (upstream #33)

When a user interrupted a drill session to edit or capture, the
session's end-pos slot got set to a marker (or :quit).  The end-of-
org-drill cond branched on end-pos: if set, show resume message and
skip org-drill-final-report.

That worked for the first interruption.  But on org-drill-resume,
the session was reused with end-pos still carrying the prior marker.
Even when the resumed session completed normally, the same cond
branch fired again — silently skipping final-report.

Clear end-pos at the top of org-drill when resume-p is non-nil, per
Markus's proposed patch on the upstream issue.  The resumed session
can now reach the final-report branch.

2 files changed, 64 insertions, 0 deletions

diff --git a/org-drill.el b/org-drill.el
index f996f15..6872d29 100644
--- a/org-drill.el
+++ b/org-drill.el
@@ -3150,6 +3150,13 @@ work correctly with older versions of org mode. Your org mode version (%s) appea
            (setq org-drill-last-session
                  (org-drill-session)))))
     (cl-block org-drill
+      ;; Clear stale `end-pos' on resume.  The slot was set when the
+      ;; user interrupted the previous session (edit / quit), and
+      ;; carrying it over makes the post-resume `(if (oref session
+      ;; end-pos) ...)' branch fire — silently skipping
+      ;; `org-drill-final-report' (upstream issue #33).
+      (when resume-p
+        (setf (oref session end-pos) nil))
       (unless resume-p
         (org-drill-free-markers session t)
         (setf (oref session cram-mode) cram
diff --git a/tests/test-org-drill-resume-clears-end-pos.el b/tests/test-org-drill-resume-clears-end-pos.el
new file mode 100644
index 0000000..3f3e1b8
--- /dev/null
+++ b/tests/test-org-drill-resume-clears-end-pos.el
@@ -0,0 +1,57 @@
+;;; test-org-drill-resume-clears-end-pos.el --- Regression for #33  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Upstream issue #33 (2020-05).  When a user interrupted a drill
+;; session to edit or capture, `org-drill-entries' set the session's
+;; `end-pos' slot.  The end-of-`org-drill' cond branched on `end-pos':
+;; if set, show "you can resume" and skip `org-drill-final-report'.
+;;
+;; That worked for the first interruption.  But on subsequent
+;; `org-drill-resume', the session was reused with `end-pos' still
+;; carrying the marker from before — so even when the resumed session
+;; completed normally, `final-report' was still skipped.
+;;
+;; Fix: clear `end-pos' at the top of `org-drill' when resume-p is
+;; non-nil, so the session can again reach the final-report branch.
+;; This matches Markus's proposed patch on the upstream issue.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+(require 'org)
+(require 'org-drill)
+
+;;;; Regression — #33
+
+(ert-deftest test-org-drill-resume-clears-stale-end-pos ()
+  "An org-drill resume on a session whose end-pos is still set from a
+prior interruption should clear end-pos so the resumed session can
+reach the normal final-report branch."
+  (let ((session (org-drill-session))
+        (final-report-called nil))
+    ;; Simulate a session that was interrupted by edit (end-pos = marker).
+    (let ((stale-marker (with-temp-buffer (point-marker))))
+      (oset session end-pos stale-marker))
+    (oset session start-time (float-time (current-time)))
+    ;; Set up org-drill-last-session for the resume path to find.
+    (let ((org-drill-last-session session))
+      (cl-letf (((symbol-function 'org-drill-final-report)
+                 (lambda (_) (setq final-report-called t)))
+                ((symbol-function 'org-drill--setup-display) #'ignore)
+                ((symbol-function 'org-drill--restore-display) #'ignore)
+                ((symbol-function 'org-drill-map-entries) #'ignore)
+                ((symbol-function 'org-drill-order-overdue-entries) #'ignore)
+                ((symbol-function 'org-drill-entries)
+                 (lambda (_session &optional _resume) nil))
+                ((symbol-function 'org-drill-free-markers) #'ignore)
+                ((symbol-function 'persist-save) #'ignore)
+                ((symbol-function 'sit-for) #'ignore))
+        (org-drill nil nil t nil)
+        ;; The resumed session completed normally — end-pos cleared,
+        ;; final-report fired.
+        (should final-report-called)))))
+
+(provide 'test-org-drill-resume-clears-end-pos)
+
+;;; test-org-drill-resume-clears-end-pos.el ends here