Add unit test for lifetime dependence related to function types

Author: meg-gupta

test/Sema/lifetime_dependence_functype.swift

@@ -0,0 +1,47 @@
+// RUN: %target-typecheck-verify-swift -enable-experimental-feature NonescapableTypes
+ // REQUIRES: asserts
+
+ struct NC: ~Copyable {
+   var ne: NE {
+     NE()
+   }
+ }
+
+ struct NE: ~Escapable {
+   @_unsafeNonescapableResult
+   init() {}
+ }
+
+ func transfer(_ ne: NE) -> NE {
+   ne
+ }
+
+ func applyAnnotatedTransfer(ne: NE, transfer: (NE) -> dependsOn(0) NE) -> NE { // expected-error{{lifetime dependencies on function types are not supported}}
+   transfer(ne)
+ }
+
+ func applyTransfer(ne: NE, transfer: (NE) ->  NE) -> NE {
+   transfer(ne)
+ }
+
+ func testTransfer(nc: consuming NC) {
+   let transferred = applyTransfer(ne: nc.ne, transfer: transfer) // expected-error{{cannot convert value of type '(NE) -> _inherit(0)  NE' to expected argument type '(NE) -> NE'}}
+
+   _ = consume nc
+   _ = transfer(transferred)
+ }
+
+ func borrow(_ nc: borrowing NC) -> NE {
+   nc.ne
+ }
+
+ func applyBorrow(nc: borrowing NC, borrow: (borrowing NC) -> NE) -> NE {
+   borrow(nc)
+ }
+
+ func testBorrow(nc: consuming NC) {
+   let borrowed = applyBorrow(nc: nc, borrow: borrow) // expected-error{{cannot convert value of type '(borrowing NC) -> _scope(0)  NE' to expected argument type '(borrowing NC) -> NE}}
+   _ = consume nc
+   _ = transfer(borrowed)
+ }
+