Investigate use of `TimeProvider` for TestFramework

[christothes]

https://www.nuget.org/packages/Microsoft.Bcl.TimeProvider

[pallavit]

Is this specifically for the timeouts?

[christothes]

No - this is a type new to .NET 8, but also available as a standalone package that allows mocking of time for APIs like Task.Delay and CancellationTokens.

More info here:
https://devblogs.microsoft.com/dotnet/fake-it-til-you-make-it-to-production/

[pallavit]

Thanks, what do we use today for this scenario? Or do we not support it at all?

[christothes]

I think the closest thing we have is AsyncGate.

Mostly what we do today is introduce artificially short wait durations for testing components that wait for clock time or rely on specific cancellation timeout logic. TimeProvider allows you to keep the same wait/cancellation logic and modify the advancement of time instead.

[pallavit]

Ooh - sounds like a good addition! We should do this!

[christothes]

note for dependencies pulled in by Microsoft.Bcl.TimeProvider. According to our docs about package versions and their effect on Azure Functions and PowerShell:

• Functions marks the Microsoft.Bcl.AsyncInterfaces dependency as "resolutionPolicy": "private", so that seems safe.
• PowerShell indicates that it's version dependency on Microsoft.Bcl.AsyncInterfaces is on version 5.0.0. So that seems like it could be a problem. However, looking at this PR, it may be ok for this dependency. Need to investigate.

[christothes]

follow up on PowerShell:
PowerShell v7.2.x is using the 5.0.0 version and v7.3.x is using the 7.0.0 version of the package, so there could be loading conflicts when someone is using the latest Azure SDKs with those versions of PowerShell. But it will be good when using the latest v7.4.x PowerShell.

Support Lifecycle for the older versions is here