1 files changed, 54 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/wasm/gc/cast-extern.js b/js/src/jit-test/tests/wasm/gc/cast-extern.js
new file mode 100644
index 0000000000..9fd9ddf2c9
--- /dev/null
+++ b/js/src/jit-test/tests/wasm/gc/cast-extern.js
@@ -0,0 +1,54 @@
+// |jit-test| skip-if: !wasmGcEnabled()
+
+// Casting an external value is an expected failure
+let { refCast, refTest, brOnCast, brOnCastFail } = wasmEvalText(`
+  (module
+    (; give this struct a unique identity to avoid conflict with
+       the struct type defined in wasm.js ;)
+    (type (struct i64 i32 i64 i32))
+
+    (func (export "refTest") (param externref) (result i32)
+      local.get 0
+      extern.internalize
+      ref.test (ref 0)
+    )
+    (func (export "refCast") (param externref) (result i32)
+      local.get 0
+      extern.internalize
+      ref.cast (ref null 0)
+      drop
+      i32.const 0
+    )
+    (func (export "brOnCast") (param externref) (result i32)
+      (block (result (ref 0))
+        local.get 0
+        extern.internalize
+        br_on_cast 0 anyref (ref 0)
+        drop
+        i32.const 0
+        br 1
+      )
+      drop
+      i32.const 1
+    )
+    (func (export "brOnCastFail") (param externref) (result i32)
+      (block (result anyref)
+        local.get 0
+        extern.internalize
+        br_on_cast_fail 0 anyref (ref 0)
+        drop
+        i32.const 1
+        br 1
+      )
+      drop
+      i32.const 0
+    )
+  )
+`).exports;
+
+for (let v of WasmNonNullExternrefValues) {
+  assertErrorMessage(() => refCast(v), WebAssembly.RuntimeError, /bad cast/);
+  assertEq(refTest(v), 0);
+  assertEq(brOnCast(v), 0);
+  assertEq(brOnCastFail(v), 0);
+}