diff --git a/tests/foo/1.0/IFoo.hal b/tests/foo/1.0/IFoo.hal
index ea69e1e..fc76c1c 100644
--- a/tests/foo/1.0/IFoo.hal
+++ b/tests/foo/1.0/IFoo.hal
@@ -33,6 +33,13 @@
         blah = goober
     };
 
+    enum BitField : uint8_t {
+        V0 = 1 << 0,
+        V1 = 1 << 1,
+        V2 = 1 << 2,
+        V3 = 1 << 3,
+    };
+
     struct Fumble {
         Outer.Inner data;
     };
@@ -85,6 +92,12 @@
         int32_t guard;
     };
 
+    struct MyMask {
+        bitfield<BitField> value;
+    };
+
+    typedef bitfield<BitField> Mask;
+
     doThis(float param);
     doThatAndReturnSomething(int64_t param) generates (int32_t result);
     doQuiteABit(int32_t a, int64_t b, float c, double d) generates (double something);