pub fn call_kind<'tcx>(
    tcx: TyCtxt<'tcx>,
    param_env: ParamEnv<'tcx>,
    method_did: DefId,
    method_args: GenericArgsRef<'tcx>,
    fn_call_span: Span,
    from_hir_call: bool,
    self_arg: Option<Ident>
) -> CallKind<'tcx>