Type declaration isn't type checked when type inherits unknown type

[auduchinok]

namespace ClassLibrary16

type T() =
    inherit Foo()

    let x = Some 123
    do
        match x with
        | Some n -> printfn "%s" n
        | _ -> ()
    
    member x.Bar() = 123

[TIHan]

Can you double check to make sure this isn't a tooling issue on your end? I'm not convinced this is a compiler issue yet because I don't see this behavior in VS:

[vasily-kirichenko]

@TIHan You forget to comment or delete Foo class.

[auduchinok]

@TIHan There's no Foo type declaration in the example.

[TIHan]

I see. My mistake. I'm able to reproduce.

I also notice I lose highlighting.

Yes, this is a compiler issue.

[dsyme]

This is another case of phased error reporting. These aren't considered bugs.

[dsyme]

I'll reopen this as feature improvement since actually checking the contents of the type would presumably give better tooling results.

[dsyme]

Another repro: #5924