Add new tests for uses of mutably borrowed paths

src/test/compile-fail/borrowck-use-mut-borrow.rs

+// Copyright 2014 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.
+
+struct A { a: int, b: int }
+struct B { a: int, b: Box<int> }
+
+fn var_copy_after_var_borrow() {
+    let mut x: int = 1;
+    let p = &mut x;
+    drop(x); //~ ERROR cannot use `x` because it was mutably borrowed
+    *p = 2;
+}
+
+fn var_copy_after_field_borrow() {
+    let mut x = A { a: 1, b: 2 };
+    let p = &mut x.a;
+    drop(x); //~ ERROR cannot use `x` because it was mutably borrowed
+    *p = 3;
+}
+
+fn field_copy_after_var_borrow() {
+    let mut x = A { a: 1, b: 2 };
+    let p = &mut x;
+    drop(x.a); //~ ERROR cannot use `x.a` because it was mutably borrowed
+    p.a = 3;
+}
+
+fn field_copy_after_field_borrow() {
+    let mut x = A { a: 1, b: 2 };
+    let p = &mut x.a;
+    drop(x.a); //~ ERROR cannot use `x.a` because it was mutably borrowed
+    *p = 3;
+}
+
+fn fu_field_copy_after_var_borrow() {
+    let mut x = A { a: 1, b: 2 };
+    let p = &mut x;
+    let y = A { b: 3, .. x }; //~ ERROR cannot use `x.a` because it was mutably borrowed
+    drop(y);
+    p.a = 4;
+}
+
+fn fu_field_copy_after_field_borrow() {
+    let mut x = A { a: 1, b: 2 };
+    let p = &mut x.a;
+    let y = A { b: 3, .. x }; //~ ERROR cannot use `x.a` because it was mutably borrowed
+    drop(y);
+    *p = 4;
+}
+
+fn var_deref_after_var_borrow() {
+    let mut x: Box<int> = box 1;
+    let p = &mut x;
+    drop(*x); //~ ERROR cannot use `*x` because it was mutably borrowed
+    **p = 2;
+}
+
+fn field_deref_after_var_borrow() {
+    let mut x = B { a: 1, b: box 2 };
+    let p = &mut x;
+    drop(*x.b); //~ ERROR cannot use `*x.b` because it was mutably borrowed
+    p.a = 3;
+}
+
+fn field_deref_after_field_borrow() {
+    let mut x = B { a: 1, b: box 2 };
+    let p = &mut x.b;
+    drop(*x.b); //~ ERROR cannot use `*x.b` because it was mutably borrowed
+    **p = 3;
+}
+
+fn main() {
+    var_copy_after_var_borrow();
+    var_copy_after_field_borrow();
+
+    field_copy_after_var_borrow();
+    field_copy_after_field_borrow();
+
+    fu_field_copy_after_var_borrow();
+    fu_field_copy_after_field_borrow();
+
+    var_deref_after_var_borrow();
+    field_deref_after_var_borrow();
+    field_deref_after_field_borrow();
+}
+

src/test/run-pass/borrowck-use-mut-borrow.rs

+// Copyright 2014 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.
+
+struct A { a: int, b: Box<int> }
+
+fn field_copy_after_field_borrow() {
+    let mut x = A { a: 1, b: box 2 };
+    let p = &mut x.b;
+    drop(x.a);
+    **p = 3;
+}
+
+fn fu_field_copy_after_field_borrow() {
+    let mut x = A { a: 1, b: box 2 };
+    let p = &mut x.b;
+    let y = A { b: box 3, .. x };
+    drop(y);
+    **p = 4;
+}
+
+fn field_deref_after_field_borrow() {
+    let mut x = A { a: 1, b: box 2 };
+    let p = &mut x.a;
+    drop(*x.b);
+    *p = 3;
+}
+
+fn field_move_after_field_borrow() {
+    let mut x = A { a: 1, b: box 2 };
+    let p = &mut x.a;
+    drop(x.b);
+    *p = 3;
+}
+
+fn fu_field_move_after_field_borrow() {
+    let mut x = A { a: 1, b: box 2 };
+    let p = &mut x.a;
+    let y = A { a: 3, .. x };
+    drop(y);
+    *p = 4;
+}
+
+fn main() {
+    field_copy_after_field_borrow();
+    fu_field_copy_after_field_borrow();
+    field_deref_after_field_borrow();
+    field_move_after_field_borrow();
+    fu_field_move_after_field_borrow();
+}
+