csharp_style_var_when_type_is_apparent breaks when awaiting a generic type

[mslukebo]

Version Used: net6.0, netcoreapp3.1

Summary:

When specifying csharp_style_var_when_type_is_apparent: true, the formatter thinks await Task.Run(() => SomeMethodThatReturnsAGenericallyTypedResult())'s type is "apparent" and awaiting the value forces you to use var

Steps to Reproduce:

1. Create a new solution and add an .editorconfig whose content is

[*.cs]
csharp_style_var_when_type_is_apparent = true:warning

2. In Program.cs, paste the following code:

using System.Collections.Generic;
using System.Threading.Tasks;

public class Program
{
    public static async Task Main()
    {
        object test1 = DoSomeWork();
        object test2 = await Task.Run(() => DoSomeWork());

        IEnumerable<object> test3 = DoSomeWorkGeneric();
        IEnumerable<object> test4 = await Task.Run(() => DoSomeWorkGeneric());
    }

    public static object DoSomeWork()
    {
        return new object();
    }

    public static IEnumerable<object> DoSomeWorkGeneric()
    {
        return new List<object>();
    }
}

Expected Behavior:

All four of the variables should require specifying the type, yielding no warnings in the above code.

Actual Behavior:

test4's type has a warning that says it should use var:

[jasonmalinowski]

@CyrusNajmabadi @sharwell Before I triage out: does this request match your expectation for what "is apparent" is supposed to do here? I know it's not as well specced as we'd like...

[CyrusNajmabadi]

Neither of these cases seem apparant to me. THere's nothing on the RHS that makes me understand what the type should be.

[jasonmalinowski]

@CyrusNajmabadi That was my thought, but wasn't sure if there was some funky logic here.

[CyrusNajmabadi]

Closing out as by design. These cases are not apparent.

[mslukebo]

@CyrusNajmabadi closing this as "by design" because "these cases are not apparent" appears like a misunderstanding of the bug report.

It is agreed that all 4 cases are "not apparent." The issue is the linter thinks test4 is apparent, and wants you to use var.

[CyrusNajmabadi]

Indeed. Reactivated