1 files changed, 39 insertions, 0 deletions
diff --git a/tests/ui/borrowck/borrowck-assign-comp-idx.rs b/tests/ui/borrowck/borrowck-assign-comp-idx.rs
new file mode 100644
index 000000000..f4dffeb8c
--- /dev/null
+++ b/tests/ui/borrowck/borrowck-assign-comp-idx.rs
@@ -0,0 +1,39 @@
+struct Point {
+    x: isize,
+    y: isize,
+}
+
+fn a() {
+    let mut p = vec![1];
+
+    // Create an immutable pointer into p's contents:
+    let q: &isize = &p[0];
+
+    p[0] = 5; //~ ERROR cannot borrow
+
+    println!("{}", *q);
+}
+
+fn borrow<F>(_x: &[isize], _f: F) where F: FnOnce() {}
+
+fn b() {
+    // here we alias the mutable vector into an imm slice and try to
+    // modify the original:
+
+    let mut p = vec![1];
+
+    borrow(
+        &p,
+        || p[0] = 5); //~ ERROR cannot borrow `p` as mutable
+}
+
+fn c() {
+    // Legal because the scope of the borrow does not include the
+    // modification:
+    let mut p = vec![1];
+    borrow(&p, ||{});
+    p[0] = 5;
+}
+
+fn main() {
+}