VSTHRD110 fires in Expression-valued scenarios

[iouri-s]

Bug description

When a Task-valued lambda is passed into a method expecting an Expression<> argument, VSTRD110 shouldn't fire, because no invocation is likely being made.

Repro steps

Code to reproduce the behavior.

Write a test using Moq library in VisualStudio:

using Moq;

var mock = new Mock<ILogger>();
mock.Verify(
    x => x.InfoAsync(It.IsAny<string>()),
    Times.Never,
    "No Log should have been written");

public interface ILogger
{
    Task InfoAsync(string message);
}

Expected behavior

No warning.

Actual behavior

VSTHRD110 warning.

• Version used: 17.5.22
• Application (if applicable):
  Microsoft Visual Studio Enterprise 2022 (64-bit) - Current
  Version 17.4.5

Additional context

Add any other context about the problem here.

[AArnott]

Thank you for this report. It makes sense and I agree with your suggestion.

[whyleee]

As a simple workaround for this issue, use a Times object instead of a method group. For example, use Times.Never() instead of Times.Never:

mock.Verify(
    x => x.InfoAsync(It.IsAny<string>()),
    Times.Never(),
    "No Log should have been written");

This will not trigger VSTHRD110 warning, because another Verify method overload with Func<Task> will be used instead of an overload with Action<T> that doesn't not return a task to the caller.