dotnet/runtime

[Analyzer] Async methods that don't take a CancellationToken

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#78,397 opened on Nov 15, 2022

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 (7 comments) (11 reactions) (1 assignee)C# (5,445 forks)batch import
api-approvedarea-System.Threading.Taskscode-analyzerhelp wanted

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Description

Cancellation is often important to the scalability of an app / service. If an async method has no way to cancel it, that can impact scalability and responsiveness. We should consider adding an analyzer (likely off by default due to noise) that flags async methods (async and/or Task/ValueTask-returning) that have no overloads which accept a CancellationToken, and issue a diagnostic to consider taking one.

Contributor guide

Research direction
Explore Roslyn analyzer documentation and implement a diagnostic that flags async methods (async or Task/ValueTask returning) lacking a CancellationToken parameter. Consider making it off by default with a severity suggestion.
Tech stack
csharp
Domain
tooling
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
3-5 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C#Roslyn analyzersasync/awaitCancellationToken
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
50