Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/src/test/ui/nll/match-guards-always-borrow.rs b/src/test/ui/nll/match-guards-always-borrow.rs
new file mode 100644
index 000000000..87dba187b
--- /dev/null
+++ b/src/test/ui/nll/match-guards-always-borrow.rs
@@ -0,0 +1,41 @@
+// Here is arielb1's basic example from rust-lang/rust#27282
+// that AST borrowck is flummoxed by:
+
+fn should_reject_destructive_mutate_in_guard() {
+    match Some(&4) {
+        None => {},
+        ref mut foo if {
+            (|| { let bar = foo; bar.take() })();
+            //~^ ERROR cannot move out of `foo` in pattern guard [E0507]
+            false } => { },
+        Some(s) => std::process::exit(*s),
+    }
+}
+
+// Here below is a case that needs to keep working: we only use the
+// binding via immutable-borrow in the guard, and we mutate in the arm
+// body.
+fn allow_mutate_in_arm_body() {
+    match Some(&4) {
+        None => {},
+        ref mut foo if foo.is_some() && false => { foo.take(); () }
+        Some(s) => std::process::exit(*s),
+    }
+}
+
+// Here below is a case that needs to keep working: we only use the
+// binding via immutable-borrow in the guard, and we move into the arm
+// body.
+fn allow_move_into_arm_body() {
+    match Some(&4) {
+        None => {},
+        mut foo if foo.is_some() && false => { foo.take(); () }
+        Some(s) => std::process::exit(*s),
+    }
+}
+
+fn main() {
+    should_reject_destructive_mutate_in_guard();
+    allow_mutate_in_arm_body();
+    allow_move_into_arm_body();
+}