Prehistory

Once we run into the deadlock issue with AzureFunction. The instance was sometimes crashing with a very strange exception. My colleague Dimitar Nikolov assumed that probably there is a deadlock issue. Then we found accessing .Result property on Task instead of awaiting it. Which leads to deadlock.

Solution

I come to a solution that probably there is an analyzer to handle such cases. Hopefully, I found one in the Microsoft's repository. Unfortunately, there were several problems. The analyzer wasn't checking if property/field/variable returns Task type and was checking only methods with async prefix declaration.

My changes in the analyzer are:

1. Changed to work in any method type (previously worked only in async methods)
2. Check returning type for MemberAccessExpressionSyntax to be Task
3. Removed checking for Sleep() because Task doesn't contain this definition
4. The .GetResult() case moved to separate analyzer. Because C# evolves and we may have different types to await.

My skills weren't enough to update and migrate code fixing.

Notes

Roslyn-analyzers repository deleted some set of analyzers which include this too. They advised to use threading analyzers from the vs-threading repository.