1 files changed, 12 insertions, 0 deletions
diff --git a/src/test/ui/lint/unused-braces-while-let-with-mutable-value.rs b/src/test/ui/lint/unused-braces-while-let-with-mutable-value.rs
new file mode 100644
index 000000000..ac547293c
--- /dev/null
+++ b/src/test/ui/lint/unused-braces-while-let-with-mutable-value.rs
@@ -0,0 +1,12 @@
+// check-pass
+
+#![deny(unused_braces)]
+
+fn main() {
+    let mut a = Some(3);
+    // Shouldn't warn below `a`.
+    while let Some(ref mut v) = {a} {
+        a.as_mut().map(|a| std::mem::swap(a, v));
+        break;
+    }
+}