Add tests for Borrow(Mut) for slices (#202)

Author: tarcieri

tests/mod.rs

@@ -88,6 +88,14 @@ fn borrow_identity() {
     assert_eq!(&array, array_ref);
 }
 
+#[test]
+fn borrow_slice() {
+    type A = Array<u8, U2>;
+    let array: A = Array([1, 2]);
+    let slice: &[u8] = array.borrow();
+    assert_eq!(array.as_slice(), slice);
+}
+
 #[test]
 fn borrow_mut_identity() {
     type A = Array<u8, U2>;
@@ -104,6 +112,14 @@ fn borrow_mut_core_array() {
     assert_eq!(&[1, 2], array_ref);
 }
 
+#[test]
+fn borrow_mut_slice() {
+    type A = Array<u8, U2>;
+    let mut array: A = Array([1, 2]);
+    let slice: &mut [u8] = array.borrow_mut();
+    assert_eq!(&[1, 2], slice);
+}
+
 #[test]
 fn cast_slice_from_core() {
     type A = Array<u8, U2>;