Analyzer: Warn when passing a Task<T> or ValueTask<T> to Minimal API Results.* methods

[martincostello]

Is your feature request related to a problem? Please describe.

Playing around with Minimal APIs, I wrote some code similar to the below without noticing I'd forgotten to await the method:

app.MapGet("/do-thing", (IThingDoer thing) => Results.Json(thing.DoThingAsync()));

Calling /do-thing then returned some JSON similar to the below:

{"result":{},"id":1,"exception":null,"status":5,"isCanceled":false,"isCompleted":true,"isCompletedSuccessfully":true,"creationOptions":0,"asyncState":null,"isFaulted":false}

Easily fixed by updating the method signature appropriately, but an easy enough mistake to make.

app.MapGet("/do-thing", async (IThingDoer thing) => Results.Json(await thing.DoThingAsync()));

Describe the solution you'd like

An analyzer that warns if a "task-like" type (Task, Task<T>, ValueTask, ValueTask<T>) is passed to one of the static Results methods (like Results.Json(object? data, ...)) for a parameter of type object?.

[rafikiassumani-msft]

Triage: We will evaluate to commit to this work with other analyzers for .NET7 planning.

[ghost]

Thanks for contacting us.

We're moving this issue to the .NET 8 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.