[bug] Não permitir que usuário acessem tasks para contests não iniciados ou cancelados

apps/tasks/tests.py

@@ -179,3 +179,14 @@ def test_send_submission_is_redirecting(self) -> None:
     def test_send_submission_without_authentication(self) -> None:
         response = self.client.post(self.url, data={"code": self.code})
         self.assertEqual(response.status_code, 302)
+
+    def test_access_task_that_is_accessible(self) -> None:
+        response = self.client.get(self.url)
+        self.assertEqual(response.status_code, 200)
+
+    def test_access_task_that_is_not_accessible(self) -> None:
+        self.task.contest.cancelled = True
+        self.task.contest.save()
+
+        response = self.client.get(self.url)
+        self.assertEqual(response.status_code, 302)

apps/tasks/views.py

@@ -32,6 +32,17 @@ def get_context_data(self, **kwargs: Any) -> Dict[str, Any]:
     def get_success_url(self) -> str:
         return reverse("tasks:detail", args=[self.object.id])
 
+    def get(
+        self, request: HttpRequest, *args: Any, **kwargs: Any
+    ) -> HttpResponse:
+        self.object = self.get_object()
+
+        if not self.object.is_accessible:
+            return redirect("home")
+
+        context = self.get_context_data(object=self.object)
+        return self.render_to_response(context)
+
     def post(self, request: HttpRequest, *, pk: int) -> HttpResponse:
         # Unauthenticated users should not be able to submit
         # a submission to a task, so we redirect them to the