Add with_list_account scope to List model (#35539)

spec/models/list_spec.rb

@@ -28,4 +28,26 @@ RSpec.describe List do
       end
     end
   end
+
+  describe 'Scopes' do
+    describe '.with_list_account' do
+      let(:alice) { Fabricate :account }
+      let(:bob) { Fabricate :account }
+      let(:list) { Fabricate :list }
+      let(:other_list) { Fabricate :list }
+
+      before do
+        Fabricate :follow, account: list.account, target_account: alice
+        Fabricate :follow, account: other_list.account, target_account: bob
+        Fabricate :list_account, list: list, account: alice
+        Fabricate :list_account, list: other_list, account: bob
+      end
+
+      it 'returns lists connected to the account' do
+        expect(described_class.with_list_account(alice))
+          .to include(list)
+          .and not_include(other_list)
+      end
+    end
+  end
 end