1 files changed, 109 insertions, 0 deletions
diff --git a/src/test/ui/pattern/bindings-after-at/borrowck-pat-ref-mut-twice.rs b/src/test/ui/pattern/bindings-after-at/borrowck-pat-ref-mut-twice.rs
new file mode 100644
index 000000000..99739c7bc
--- /dev/null
+++ b/src/test/ui/pattern/bindings-after-at/borrowck-pat-ref-mut-twice.rs
@@ -0,0 +1,109 @@
+// Test that `ref mut x @ ref mut y` and varieties of that are not allowed.
+
+fn main() {
+    struct U;
+
+    fn u() -> U { U }
+
+    fn f1(ref mut a @ ref mut b: U) {}
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    fn f2(ref mut a @ ref mut b: U) {}
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    fn f3(
+        ref mut a @ [
+        //~^ ERROR cannot borrow value as mutable more than once at a time
+            [ref b @ .., _],
+            [_, ref mut mid @ ..],
+            ..,
+            [..],
+        ] : [[U; 4]; 5]
+    ) {}
+    fn f4_also_moved(ref mut a @ ref mut b @ c: U) {}
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    //~| ERROR cannot move out of value because it is borrowed
+    //~| ERROR borrow of moved value
+
+    let ref mut a @ ref mut b = U;
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    drop(a);
+    let ref mut a @ ref mut b = U;
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    //~| ERROR cannot borrow value as mutable more than once at a time
+    drop(b);
+    let ref mut a @ ref mut b = U;
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+
+    let ref mut a @ ref mut b = U;
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    *a = U;
+    let ref mut a @ ref mut b = U;
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+    //~| ERROR cannot borrow value as mutable more than once at a time
+    *b = U;
+
+    let ref mut a @ (
+    //~^ ERROR cannot borrow value as mutable more than once at a time
+        ref mut b,
+        [
+            ref mut c,
+            ref mut d,
+            ref e,
+        ]
+    ) = (U, [U, U, U]);
+
+    let ref mut a @ (
+        //~^ ERROR cannot borrow value as mutable more than once at a time
+            ref mut b,
+            [
+                ref mut c,
+                ref mut d,
+                ref e,
+            ]
+        ) = (u(), [u(), u(), u()]);
+
+    let a @ (ref mut b, ref mut c) = (U, U);
+    //~^ ERROR borrow of moved value
+    let mut val = (U, [U, U]);
+    let a @ (b, [c, d]) = &mut val; // Same as ^--
+    //~^ ERROR borrow of moved value
+
+    let a @ &mut ref mut b = &mut U;
+    //~^ ERROR borrow of moved value
+    let a @ &mut (ref mut b, ref mut c) = &mut (U, U);
+    //~^ ERROR borrow of moved value
+
+    match Ok(U) {
+        ref mut a @ Ok(ref mut b) | ref mut a @ Err(ref mut b) => {
+            //~^ ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+        }
+    }
+    match Ok(U) {
+        ref mut a @ Ok(ref mut b) | ref mut a @ Err(ref mut b) => {
+            //~^ ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            *b = U;
+        }
+    }
+    match Ok(U) {
+        ref mut a @ Ok(ref mut b) | ref mut a @ Err(ref mut b) => {
+            //~^ ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            *a = Err(U);
+
+            // FIXME: The binding name value used above makes for problematic diagnostics.
+            // Resolve that somehow...
+        }
+    }
+    match Ok(U) {
+        ref mut a @ Ok(ref mut b) | ref mut a @ Err(ref mut b) => {
+            //~^ ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            //~| ERROR cannot borrow value as mutable more than once at a time
+            drop(a);
+        }
+    }
+}