dotnet/runtime

Rewrite 3 MemoryCache tests to not be timing sensitive

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#72,890 opened on Jul 26, 2022

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 (2 comments) (0 reactions) (0 assignees)C# (5,445 forks)batch import
area-Extensions-Cachingdisabled-testhelp wanted

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Description

GetAndSet_AreThreadSafe_AndUpdatesNeverLeavesNullValues OvercapacityPurge_AreThreadSafe AddAndReplaceEntries_AreThreadSafe

These were inherited from aspnet/caching but have been disabled as they need rewriting to not be racy.

example failure

System.AggregateException : One or more errors occurred.
---- System.Threading.Tasks.TaskCanceledException : A task was canceled.


Stack trace
   at System.Threading.Tasks.Task.WaitAll(Task[] tasks, Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at Microsoft.Extensions.Caching.Memory.MemoryCacheSetAndRemoveTests.OvercapacityPurge_AreThreadSafe() in /_/src/libraries/Microsoft.Extensions.Caching.Memory/tests/MemoryCacheSetAndRemoveTests.cs:line 655
----- Inner Stack Trace -----

Contributor guide

Research direction
Inspect the three failing tests (GetAndSet AreThreadSafe AndUpdatesNeverLeavesNullValues, OvercapacityPurge AreThreadSafe, AddAndReplaceEntries AreThreadSafe) and understand the timing dependent race conditions. Then rewrite them to use synchronization primitives (e.g., ManualResetEvent, CountdownEvent) or deterministic interleaving to avoid timing sensitivity.
Tech stack
csharp
Domain
backend
Issue type
Test
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C#unit testingthreading basics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70