1 files changed, 8 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/promise/promise-cross-compartment-subclassing.js b/js/src/jit-test/tests/promise/promise-cross-compartment-subclassing.js
new file mode 100644
index 000000000..dc77b3956
--- /dev/null
+++ b/js/src/jit-test/tests/promise/promise-cross-compartment-subclassing.js
@@ -0,0 +1,8 @@
+const global = newGlobal();
+const OtherPromise = global.Promise;
+class SubPromise extends OtherPromise {}
+
+assertEq(true, new SubPromise(()=>{}) instanceof OtherPromise);
+assertEq(true, SubPromise.resolve({}) instanceof OtherPromise);
+assertEq(true, SubPromise.reject({}) instanceof OtherPromise);
+assertEq(true, SubPromise.resolve({}).then(()=>{}, ()=>{}) instanceof OtherPromise);