Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
| Property | Value |
|---|---|
| Rule ID | MSTEST0040 |
| Title | Do not assert inside 'async void' contexts |
| Category | Usage |
| Fix is breaking or non-breaking | Non-breaking |
| Enabled by default | Yes |
| Default severity | Warning |
| Introduced in version | 3.8.0 |
| Is there a code fix | No |
Cause
The use of any assertion method in an async void method, local function, or lambda.
Rule description
Exceptions that are thrown in an async void context are unhandled. A failing assertion in an async void method will be swallowed and will not crash the process when using VSTest under .NET Framework. Under .NET, a failing assertion in an async void method might crash the process when using Microsoft.Testing.Platform or VSTest. In cases where a custom SynchronizationContext is present that catches the exception, the failing assertion might be silently swallowed.
How to fix violations
Refactor the code to not use assertions in async void.
When to suppress warnings
Do not suppress a warning from this rule.
Collaborate with us on GitHub
The source for this content can be found on GitHub, where you can also create and review issues and pull requests. For more information, see our contributor guide.
