Description

When dealing with F#-async workflows and exposing these APIs as public, we often forget about our C#-dev friends (that prefer Task-based alternatives, which should be suffixed with "Async").

Now, if there's already a FooAsync(): Task<'Bar> method, this rule should also suggest adding F#-friendly AsyncFoo(): Async<'Bar>.

Testcases

module Foo =
    let AsyncBar(): Async<int> =
        async { return 0 }

Should give linter warning offering creation of BarAsync(): Task<int>.

module Foo =
    let private AsyncBar(): Async<int> =
        async { return 0 }

Should not give any linter warnings (because it's not public).

module Foo =
    let internal AsyncBar(): Async<int> =
        async { return 0 }

Should not give any linter warnings (because it's not public).

module Foo =
    let AsyncBar(): Async<int> =
        async { return 0 }
    let BarAsync(): Task<int> =
        null

Should not give any linter warnings (because it complies with conventions).

module Foo =
    let Bar(): Async<int> =
        { return 1 }

Should give linter warning offering creation of BarAsync(): Task<int> and rename Bar to AsyncBar.

module Foo =
    let Bar(): Async<int> =
        async { return 0 }
    let BarAsync(): Task<int> =
        null

Should give linter warning offering renaming Bar to AsyncBar.

module Foo =
    let AsyncBar(): int =
        1
    let BarAsync(): Task<int> =
        null

Should give linter warning offering renaming AsyncBar to Bar.

module Foo =
    let AsyncBar(): Async<int> =
        async { return 0 }
    let Bar(): Task<int> =
        null

Should give linter warning offering renaming Bar to BarAsync.

module Foo =
    let AsyncBar(): Async<unit> =
        Async.Sleep 5.0

Should give linter warning offering creation of BarAsync(): Task (because unit in C# doesn't exist).

module Foo =
    let Bar(): Async<unit> =
        Async.Sleep 5.0

Should give linter warning offering creation of BarAsync(): Task (because unit in C# doesn't exist), and rename Bar to AsyncBar.