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await Task.WhenAny(new List<Task>()) should not Hang #55578
Description
Description
Run this code:
await Task.WhenAny(new List<Task>())
And it will hang your process.
This is a highly undesirable default behavior. It is not obvious this will hang and there is no easy way to detect that this was the cause.
Other information
I recommend one of the following adjustments:
If using Task.WhenAny() on an empty list/enumerable/array:
A) Throw a Sequence contains no elements exception.
OR
B) Immediately return Task.CompletedTask or Task.FromResult(default(T))
I am OK with either, but I think that A is the best option.
Activity
stephentoub commentedon Jul 13, 2021
This is a regression in .NET 6 caused by #38896. It throws an ArgumentException as expected on previous versions.
TonyValenti commentedon Jul 13, 2021
@stephentoub Thanks!