1 files changed, 48 insertions, 0 deletions
diff --git a/src/test/ui/overloaded/overloaded-index-assoc-list.rs b/src/test/ui/overloaded/overloaded-index-assoc-list.rs
new file mode 100644
index 000000000..eb027afea
--- /dev/null
+++ b/src/test/ui/overloaded/overloaded-index-assoc-list.rs
@@ -0,0 +1,48 @@
+// run-pass
+// Test overloading of the `[]` operator.  In particular test that it
+// takes its argument *by reference*.
+
+use std::ops::Index;
+
+struct AssociationList<K,V> {
+    pairs: Vec<AssociationPair<K,V>> }
+
+#[derive(Clone)]
+struct AssociationPair<K,V> {
+    key: K,
+    value: V
+}
+
+impl<K,V> AssociationList<K,V> {
+    fn push(&mut self, key: K, value: V) {
+        self.pairs.push(AssociationPair {key: key, value: value});
+    }
+}
+
+impl<'a, K: PartialEq + std::fmt::Debug, V:Clone> Index<&'a K> for AssociationList<K,V> {
+    type Output = V;
+
+    fn index(&self, index: &K) -> &V {
+        for pair in &self.pairs {
+            if pair.key == *index {
+                return &pair.value
+            }
+        }
+        panic!("No value found for key: {:?}", index);
+    }
+}
+
+pub fn main() {
+    let foo = "foo".to_string();
+    let bar = "bar".to_string();
+
+    let mut list = AssociationList {pairs: Vec::new()};
+    list.push(foo.clone(), 22);
+    list.push(bar.clone(), 44);
+
+    assert_eq!(list[&foo], 22);
+    assert_eq!(list[&bar], 44);
+
+    assert_eq!(list[&foo], 22);
+    assert_eq!(list[&bar], 44);
+}