suggest: include receiver parameter info in method hints

[mdempsky]

It might be desirable to include receiver parameter information in hints for methods. At the very least, when hinting the type of a method expression, we should probably indicate that the method parameter has become a normal parameter.

For example, currently for bytes.Buffer.Write, we hint func Write(p []byte) (n int, err error), but the method expression's type is actually func (*bytes.Buffer, []byte) (int, error).

[segevfiner]

I don't think receivers are treated as the "first argument" by the go language... (Even if they are probably treated like that in the generated assembly).

Anyhow, knowing the functions receiver is needed in order to fix this issue in vscode-go: microsoft/vscode-go#2107.

[mdempsky]

I don't think receivers are treated as the "first argument" by the go language...

They are in the context of method expressions. For example, the type of (*bytes.Buffer).Write is func(*bytes.Buffer, []byte) (int, error). See: https://play.golang.org/p/HVzthYTo6bg

[ramya-rao-a]

cc @stamblerre