Help needed on "CS8774 Member must have a non-null value when exiting"

[qrli]

Need some help on [MemberNotNull]. I'm using Dapper.

        [MemberNotNull(nameof(dqListCache))]
        public async Task InitCacheAsync()
        {
            using var conn = connFactory.NewConnection();
            dqListCache = (await conn.QueryAsync<MyDto>("select * from MyTable")).ToList();
        }

It generates "CS8774 Member must have a non-null value when exiting." on the last line, and adding null-forgiving ! anywhere cannot mute it.

[CyrusNajmabadi]

It's possible that this is because it's task returning and async. So the method literally can return (giving the caller the task) before the value is actually set.

[CyrusNajmabadi]

What happens if you start the method with dqListCache = null! prior to any of the existing code.

[qrli]

Cool. It resolves the warning.

A bit counter intuitive, but it does work as defined. I expected [MemberNotNull] to remove null-forgiving from my code, but it seems it needs it by itself. 😂 async initialization seems a bit tricky here and there.