1 files changed, 14 insertions, 0 deletions
diff --git a/tests/ui/indexing/indexing-requires-a-uint.rs b/tests/ui/indexing/indexing-requires-a-uint.rs
new file mode 100644
index 00000000000..dbe9b44a138
--- /dev/null
+++ b/tests/ui/indexing/indexing-requires-a-uint.rs
@@ -0,0 +1,14 @@
+// Make sure that indexing an array is only valid with a `usize`, not any other
+// integral type.
+
+fn main() {
+    fn bar<T>(_: T) {}
+    [0][0u8]; //~ ERROR: the type `[{integer}]` cannot be indexed by `u8`
+
+    [0][0]; // should infer to be a usize
+
+    let i = 0;      // i is an IntVar
+    [0][i];         // i should be locked to usize
+    bar::<isize>(i);  // i should not be re-coerced back to an isize
+    //~^ ERROR: mismatched types
+}