Typechecking failure on a small example

[aseemr]

module Test

let test_t () = x:int -> Pure unit (requires x > 0) (ensures fun _ -> True)

assume val bar (x:int) : Pure unit (requires x > 0) (ensures fun _ -> True)

let foo () : (test_t ()) =
  fun x -> bar x

Stumbled on something like this in LowParse when working on #1055.

[aseemr]

This works in F* master now.