tests/ui/traits/fmt-pointer-trait.rs: Add HRTB fn pointer case

Author: Enselic

tests/ui/traits/fmt-pointer-trait.rs

@@ -3,6 +3,11 @@ use std::ptr;
 use std::rc::Rc;
 use std::sync::Arc;
 
+/// Regression test for <https://github.com/rust-lang/rust/issues/50280#issuecomment-626035934>
+fn show(a: fn () -> f32, b: fn (&Vec<i8>)->f32) {
+    println!("the two pointers: {:p} {:p}", a, b);
+}
+
 fn main() {
     let p: *const u8 = ptr::null();
     let rc = Rc::new(1usize);
@@ -21,4 +26,6 @@ fn main() {
     }
     assert_eq!(format!("{:p}", p),
                "0x0");
+
+    show(|| 1.0, |_| 2.0);
 }