LS3002: CancellationToken Is Not the Last Parameter

LS3002 is a compiler check that reports a cancellation token parameter that is not the last parameter or is not named cancellationToken, which is easy to pass in the wrong position and hides what it is where the method is called. This page states what the rule reports, where the warning sits, and how to place and name the token.

Reference#

What the rule enforces#

LS3002 enforces Name asynchronous methods completely (litespec/backend/dotnet/naming#name-asynchronous-methods-completely). It runs in all five projects. Its category is LiteSpec.Style. It reports a warning and is enabled by default, as the Analyzers overview describes.

What the rule reports#

The rule reports a CancellationToken parameter that is not the last parameter, or that is not named exactly cancellationToken. The token may sit second to last when the last parameter is a params array. The diagnostic sits on the token parameter.

Failing example#

public Task LoadAsync(CancellationToken cancellationToken, string name) => Task.CompletedTask;

Passing example#

public Task SaveAsync(CancellationToken cancellationToken, params string[] names) => Task.CompletedTask;

How to fix#

Move the token to the last position, or before a trailing params array, and name it cancellationToken.

Notes#

What the rule ignores#

The rule does not report methods without a token, overrides, explicit interface implementations, or implementations of members from outside interfaces. It does not run outside the five projects.