Test for mut in ident patterns.

src/test/compile-fail/lint-unused-mut-variables.rs

@@ -20,6 +20,14 @@ fn main() {
     let mut a = 2; //~ ERROR: variable does not need to be mutable
     let mut b = 3; //~ ERROR: variable does not need to be mutable
     let mut a = ~[3]; //~ ERROR: variable does not need to be mutable
+    let (mut a, b) = (1, 2); //~ ERROR: variable does not need to be mutable
+
+    match 30 {
+        mut x => {} //~ ERROR: variable does not need to be mutable
+    }
+
+    let x = |mut y: int| 10; //~ ERROR: variable does not need to be mutable
+    fn what(mut foo: int) {} //~ ERROR: variable does not need to be mutable
 
     // positive cases
     let mut a = 2;
@@ -30,6 +38,17 @@ fn main() {
     do callback {
         a.push(3);
     }
+    let (mut a, b) = (1, 2);
+    a = 34;
+
+    match 30 {
+        mut x => {
+            x = 21;
+        }
+    }
+
+    let x = |mut y: int| y = 32;
+    fn nothing(mut foo: int) { foo = 37; }
 }
 
 fn callback(f: &fn()) {}

src/test/compile-fail/mut-patterns.rs

@@ -0,0 +1,16 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Can't put mut in non-ident pattern
+
+pub fn main() {
+    struct Foo { x: int }
+    let mut Foo { x: x } = Foo { x: 3 }; //~ ERROR: expected `;` but found `{`
+}

src/test/run-pass/mut-in-ident-patterns.rs

@@ -0,0 +1,80 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+trait Foo {
+    fn foo(&self, mut x: int) -> int {
+        let val = x;
+        x = 37 * x;
+        val + x
+    }
+}
+
+struct X;
+impl Foo for X {}
+
+pub fn main() {
+    let (a, mut b) = (23, 4);
+    assert_eq!(a, 23);
+    assert_eq!(b, 4);
+    b = a + b;
+    assert_eq!(b, 27);
+
+
+    assert_eq!(X.foo(2), 76);
+
+    enum Bar {
+       Foo(int),
+       Baz(f32, u8)
+    }
+
+    let (x, mut y) = (32, Foo(21));
+
+    match x {
+        mut z @ 32 => {
+            assert_eq!(z, 32);
+            z = 34;
+            assert_eq!(z, 34);
+        }
+        _ => {}
+    }
+
+    check_bar(&y);
+    y = Baz(10.0, 3);
+    check_bar(&y);
+
+    fn check_bar(y: &Bar) {
+        match y {
+            &Foo(a) => {
+                assert_eq!(a, 21);
+            }
+            &Baz(a, b) => {
+                assert_eq!(a, 10.0);
+                assert_eq!(b, 3);
+            }
+        }
+    }
+
+    fn foo1((x, mut y): (f64, int), mut z: int) -> int {
+        y = 2 * 6;
+        z = y + (x as int);
+        y - z
+    }
+
+    struct A {
+        x: int
+    }
+    let A { x: mut x } = A { x: 10 };
+    assert_eq!(x, 10);
+    x = 30;
+    assert_eq!(x, 30);
+
+    (|A { x: mut t }: A| { t = t+1; t })(A { x: 34 });
+
+}