Fix error when creating or deleting a board list

Changelog: fixed

app/assets/javascripts/boards/stores/actions.js

@@ -173,8 +173,9 @@ export default {
 
   addList: ({ commit, dispatch, getters }, list) => {
     commit(types.RECEIVE_ADD_LIST_SUCCESS, updateListPosition(list));
+
     dispatch('fetchItemsForList', {
-      listId: getters.getListByTitle(ListTypeTitles.backlog).id,
+      listId: getters.getListByTitle(ListTypeTitles.backlog)?.id,
     });
   },
 
@@ -294,7 +295,7 @@ export default {
             commit(types.REMOVE_LIST_FAILURE, listsBackup);
           } else {
             dispatch('fetchItemsForList', {
-              listId: getters.getListByTitle(ListTypeTitles.backlog).id,
+              listId: getters.getListByTitle(ListTypeTitles.backlog)?.id,
             });
           }
         },
@@ -305,6 +306,8 @@ export default {
   },
 
   fetchItemsForList: ({ state, commit }, { listId, fetchNext = false }) => {
+    if (!listId) return null;
+
     if (!fetchNext) {
       commit(types.RESET_ITEMS_FOR_LIST, listId);
     }

ee/app/assets/javascripts/boards/stores/actions.js

@@ -262,6 +262,8 @@ export default {
     { state, commit, getters },
     { listId, fetchNext = false, noEpicIssues = false },
   ) => {
+    if (!listId) return null;
+
     if (!fetchNext && !state.isShowingEpicsSwimlanes) {
       commit(types.RESET_ITEMS_FOR_LIST, listId);
     }

ee/spec/frontend/boards/stores/actions_spec.js

@@ -345,6 +345,19 @@ describe('fetchItemsForList', () => {
     [listId]: pageInfo,
   };
 
+  describe('when listId is undefined', () => {
+    it('does not call the query', async () => {
+      jest.spyOn(gqlClient, 'query').mockResolvedValue(queryResponse);
+
+      await actions.fetchItemsForList(
+        { state, getters: () => {}, commit: () => {} },
+        { listId: undefined },
+      );
+
+      expect(gqlClient.query).toHaveBeenCalledTimes(0);
+    });
+  });
+
   it('add epicWildcardId with NONE as value when noEpicIssues is true', () => {
     state = {
       ...state,

spec/frontend/boards/mock_data.js

@@ -291,7 +291,7 @@ export const setMockEndpoints = (opts = {}) => {
 
 export const mockList = {
   id: 'gid://gitlab/List/1',
-  title: 'Backlog',
+  title: 'Open',
   position: -Infinity,
   listType: 'backlog',
   collapsed: false,

spec/frontend/boards/stores/actions_spec.js

@@ -715,6 +715,19 @@ describe('fetchItemsForList', () => {
     [listId]: pageInfo,
   };
 
+  describe('when list id is undefined', () => {
+    it('does not call the query', async () => {
+      jest.spyOn(gqlClient, 'query').mockResolvedValue(queryResponse);
+
+      await actions.fetchItemsForList(
+        { state, getters: () => {}, commit: () => {} },
+        { listId: undefined },
+      );
+
+      expect(gqlClient.query).toHaveBeenCalledTimes(0);
+    });
+  });
+
   it('should commit mutations REQUEST_ITEMS_FOR_LIST and RECEIVE_ITEMS_FOR_LIST_SUCCESS on success', (done) => {
     jest.spyOn(gqlClient, 'query').mockResolvedValue(queryResponse);