Fixes handling incoming unshelve activities

bookwyrm/tests/views/test_inbox.py

@@ -591,6 +591,41 @@ class Inbox(TestCase):
         views.inbox.activity_task(activity)
         self.assertEqual(shelf.books.first(), book)
 
+    def test_handle_unshelve_book(self):
+        """ remove a book from a shelf """
+        work = models.Work.objects.create(title="work title")
+        book = models.Edition.objects.create(
+            title="Test",
+            remote_id="https://bookwyrm.social/book/37292",
+            parent_work=work,
+        )
+        shelf = models.Shelf.objects.create(user=self.remote_user, name="Test Shelf")
+        shelf.remote_id = "https://bookwyrm.social/user/mouse/shelf/to-read"
+        shelf.save()
+
+        shelfbook = models.ShelfBook.objects.create(
+            user=self.remote_user, shelf=shelf, book=book
+        )
+
+        self.assertEqual(shelf.books.first(), book)
+        self.assertEqual(shelf.books.count(), 1)
+
+        activity = {
+            "id": shelfbook.remote_id,
+            "type": "Remove",
+            "actor": "https://example.com/users/rat",
+            "object": {
+                "type": "Edition",
+                "title": "Test Title",
+                "work": work.remote_id,
+                "id": "https://bookwyrm.social/book/37292",
+            },
+            "target": "https://bookwyrm.social/user/mouse/shelf/to-read",
+            "@context": "https://www.w3.org/ns/activitystreams",
+        }
+        views.inbox.activity_task(activity)
+        self.assertFalse(shelf.books.exists())
+
     @responses.activate
     def test_handle_add_book_to_list(self):
         """ listing a book """