Current state with 6 failures is considered to be better than the previous one

spec/models/list_spec.rb

@@ -163,4 +163,35 @@ describe List do
 
     describe 'product order creation'
   end
+
+  describe 'join requests' do
+    describe '#send_table_join_request_for_user' do
+      it "does not add an existing user to join_request_user_ids" do
+        list.send_table_join_request_for_user! user
+        expect(list.join_request_user_ids).not_to include user.id
+      end
+      it "adds a user to join_request_user_ids" do
+        other_user = create :user
+        list.send_table_join_request_for_user! other_user
+        # test through persistance
+        list.reload
+        expect(list.join_request_user_ids).to eq [other_user.id]
+      end
+
+      it "does not add a user multiple times" do
+        other_user = create :user
+        2.times { list.send_table_join_request_for_user! other_user }
+        expect(list.join_request_user_ids).to eq [other_user.id]
+      end
+
+      it "broadcasts it to the user" do
+        other_user = create :user
+        expect{
+          list.send_table_join_request_for_user! other_user
+        }.to broadcast_to_user(user.id).message('user_join_request').with(
+          hash_including(:users, :join_request)
+        )
+      end
+    end
+  end
 end