Gotcha when using CacheItemPolicy.RemovedCallback and relying on CacheEntryRemovedArguments

[alastairtree]

Gotcha when using CacheItemPolicy.RemovedCallback and relying on CacheEntryRemovedArguments

[alastairtree]

Hi

Thanks for the feedback. I have added a couple of tests and started exploring a potential solution on branch feat/policy-callbacks-should-unwrap-the-lazy. Fancy taking a look to see if the tests reproduce the issue you were experiencing?

[tafs7]

Just had a chance to look at it at glance. I think you may have a bug in that fix, since you never actually assign the value from the Lazy<T>.Value property in the ternary operator

Also, the recursion on the next line will introduce a StackOverflowException:

policy.RemovedCallback = (args) =>
{
    //unwrap the cache item in a removed callback given one is specified
    if (args != null && args.CacheItem != null)
    {
        var item = args.CacheItem.Value;
        if (item is Lazy<T>)
        {
            var lazyCacheItem = (Lazy<T>) item;
            args.CacheItem.Value = lazyCacheItem.IsValueCreated ? item : null; // <-- still using the Lazy object
        }
    }
    policy.RemovedCallback(args); //<-- will cause StackOverflowException
};

I'll fork and see if I can fix that so we can get this to pass. Thanks again for getting this fix started!

[alastairtree]

This should be all sorted now. Version 0.6 up on nuget. Let me know any issues and thanks for the help.