copy test cases to if let as well.

src/test/ui/binding/issue-53114-borrow-checks.rs

@@ -2,7 +2,7 @@
 // checker, and both had some deviations from our ideal state. This test
 // captures the behavior of how `_` bindings are handled with respect to how we
 // flag expressions that are meant to request unsafe blocks.
-
+#![allow(irrefutable_let_patterns)]
 struct M;
 
 fn let_wild_gets_moved_expr() {
@@ -30,6 +30,20 @@ fn match_moved_expr_to_wild() {
     //~^ ERROR [E0382]
 }
 
+fn if_let_moved_expr_to_wild() {
+    let m = M;
+    drop(m);
+    if let _ = m { } // #53114: should eventually be accepted too
+    //~^ ERROR [E0382]
+
+    let mm = (M, M); // variation on above with `_` in substructure
+    if let (_x, _) = mm { }
+    if let (_, _y) = mm { }
+    //~^ ERROR [E0382]
+    if let (_, _) = mm { }
+    //~^ ERROR [E0382]
+}
+
 fn let_wild_gets_borrowed_expr() {
     let mut m = M;
     let r = &mut m;
@@ -55,4 +69,16 @@ fn match_borrowed_expr_to_wild() {
     drop((r1, r2));
 }
 
+fn if_let_borrowed_expr_to_wild() {
+    let mut m = M;
+    let r = &mut m;
+    if let _ = m { } // accepted, and want it to continue to be
+    drop(r);
+
+    let mut mm = (M, M); // variation on above with `_` in substructure
+    let (r1, r2) = (&mut mm.0, &mut mm.1);
+    if let (_, _) = mm { }
+    drop((r1, r2));
+}
+
 fn main() { }

src/test/ui/binding/issue-53114-borrow-checks.stderr

@@ -29,6 +29,37 @@ LL |     match mm { (_, _) => { } }
    |
    = note: move occurs because `mm.1` has type `M`, which does not implement the `Copy` trait
 
-error: aborting due to 3 previous errors
+error[E0382]: use of moved value: `m`
+  --> $DIR/issue-53114-borrow-checks.rs:36:16
+   |
+34 |     let m = M;
+   |         - move occurs because `m` has type `M`, which does not implement the `Copy` trait
+35 |     drop(m);
+   |          - value moved here
+36 |     if let _ = m { } // #53114: should eventually be accepted too
+   |                ^ value used here after move
+
+error[E0382]: use of moved value: `mm`
+  --> $DIR/issue-53114-borrow-checks.rs:41:22
+   |
+40 |     if let (_x, _) = mm { }
+   |             -- value moved here
+41 |     if let (_, _y) = mm { }
+   |                      ^^ value used here after partial move
+   |
+   = note: move occurs because `mm.0` has type `M`, which does not implement the `Copy` trait
+
+error[E0382]: use of moved value: `mm`
+  --> $DIR/issue-53114-borrow-checks.rs:43:21
+   |
+41 |     if let (_, _y) = mm { }
+   |                -- value moved here
+42 |
+43 |     if let (_, _) = mm { }
+   |                     ^^ value used here after partial move
+   |
+   = note: move occurs because `mm.1` has type `M`, which does not implement the `Copy` trait
+
+error: aborting due to 6 previous errors
 
 For more information about this error, try `rustc --explain E0382`.