test: cover --route-rating-result quit/edit/skip/next branches

I added tests for `org-drill--route-rating-result' covering all four
return values: nil → 'quit (end-pos becomes :quit), 'edit → 'edit
(end-pos becomes a marker), 'skip → 'skip (current-item cleared),
quality 0 → 'next (pushes to again-entries) and quality 5 → 'next
(pushes to done-entries).  Also a case where again-entries is non-empty
so the shuffle branch runs.

Coverage moved from 91.6% to 91.7%.

1 files changed, 71 insertions, 0 deletions

diff --git a/tests/test-org-drill-route-rating-result.el b/tests/test-org-drill-route-rating-result.el
new file mode 100644
index 0000000..5469bc8
--- /dev/null
+++ b/tests/test-org-drill-route-rating-result.el
@@ -0,0 +1,71 @@
+;;; test-org-drill-route-rating-result.el --- Tests for --route-rating-result  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for `org-drill--route-rating-result', which translates the return
+;; value of `org-drill-entry' into one of `quit', `edit', `skip', `next'
+;; while updating the session queues.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+(require 'org)
+(require 'org-drill)
+
+(defun make-marker-for-test ()
+  (let ((m (make-marker))) (set-marker m 1) m))
+
+(ert-deftest test-route-rating-result-nil-returns-quit-and-stashes-end-pos ()
+  "When the entry returned nil (user quit), result is `quit' and end-pos is :quit."
+  (let ((session (org-drill-session))
+        (m (make-marker-for-test)))
+    (cl-letf (((symbol-function 'message) #'ignore))
+      (should (eq 'quit (org-drill--route-rating-result session m nil))))
+    (should (eq :quit (oref session end-pos)))))
+
+(ert-deftest test-route-rating-result-edit-stashes-marker-end-pos ()
+  "When the entry returned `edit', end-pos becomes a marker and result is `edit'."
+  (let ((session (org-drill-session))
+        (m (make-marker-for-test)))
+    (with-temp-buffer
+      (insert "x")
+      (goto-char (point-min))
+      (should (eq 'edit (org-drill--route-rating-result session m 'edit))))
+    (should (markerp (oref session end-pos)))))
+
+(ert-deftest test-route-rating-result-skip-clears-current-item ()
+  "Skip result drops the current-item slot to nil and returns `skip'."
+  (let ((session (org-drill-session))
+        (m (make-marker-for-test)))
+    (oset session current-item m)
+    (should (eq 'skip (org-drill--route-rating-result session m 'skip)))
+    (should (null (oref session current-item)))))
+
+(ert-deftest test-route-rating-result-failure-pushes-onto-again-entries ()
+  "A failed-quality result puts the marker on again-entries and returns `next'."
+  (let ((session (org-drill-session))
+        (m (make-marker-for-test)))
+    (should (eq 'next (org-drill--route-rating-result session m 0)))
+    (should (member m (oref session again-entries)))))
+
+(ert-deftest test-route-rating-result-success-pushes-onto-done-entries ()
+  "A passing-quality result puts the marker on done-entries and returns `next'."
+  (let ((session (org-drill-session))
+        (m (make-marker-for-test)))
+    (should (eq 'next (org-drill--route-rating-result session m 5)))
+    (should (member m (oref session done-entries)))))
+
+(ert-deftest test-route-rating-result-failure-with-existing-again-shuffles-it ()
+  "When again-entries already has items, the failure path re-shuffles the list."
+  (let* ((session (org-drill-session))
+         (m1 (let ((mk (make-marker))) (set-marker mk 1) mk))
+         (m2 (let ((mk (make-marker))) (set-marker mk 2) mk))
+         (shuffle-called nil))
+    (oset session again-entries (list m1 m2))
+    (cl-letf (((symbol-function 'org-drill-shuffle)
+               (lambda (lst) (setq shuffle-called t) lst)))
+      (org-drill--route-rating-result session m1 0))
+    (should shuffle-called)))
+
+(provide 'test-org-drill-route-rating-result)
+;;; test-org-drill-route-rating-result.el ends here