From 042cfad5ce9a5b80e89fb3a5e7e6df916483f58a Mon Sep 17 00:00:00 2001
From: Roberto Huertas <roberto.huertas@outlook.com>
Date: Fri, 24 Aug 2018 01:25:43 +0200
Subject: [PATCH] feat(extends): extend promise

---
 crates/js-sys/src/lib.rs            |  1 +
 crates/js-sys/tests/wasm/Promise.rs | 11 +++++++++++
 crates/js-sys/tests/wasm/main.rs    |  1 +
 3 files changed, 13 insertions(+)
 create mode 100644 crates/js-sys/tests/wasm/Promise.rs

diff --git a/crates/js-sys/src/lib.rs b/crates/js-sys/src/lib.rs
index ff2362c4..a4aa02be 100644
--- a/crates/js-sys/src/lib.rs
+++ b/crates/js-sys/src/lib.rs
@@ -3783,6 +3783,7 @@ extern {
     /// an asynchronous operation, and its resulting value.
     ///
     /// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise
+    #[wasm_bindgen(extends = Object)]
     pub type Promise;
 
     /// Creates a new `Promise` with the provided executor `cb`
diff --git a/crates/js-sys/tests/wasm/Promise.rs b/crates/js-sys/tests/wasm/Promise.rs
new file mode 100644
index 00000000..a070b784
--- /dev/null
+++ b/crates/js-sys/tests/wasm/Promise.rs
@@ -0,0 +1,11 @@
+use wasm_bindgen_test::*;
+use wasm_bindgen::JsCast;
+use js_sys::*;
+
+#[wasm_bindgen_test]
+fn promise_inheritance() {
+    let promise = Promise::new(&mut |_, _| ());
+    assert!(promise.is_instance_of::<Promise>());
+    assert!(promise.is_instance_of::<Object>());
+    let _: &Object = promise.as_ref();
+}
diff --git a/crates/js-sys/tests/wasm/main.rs b/crates/js-sys/tests/wasm/main.rs
index 285e2ae3..c72a998d 100755
--- a/crates/js-sys/tests/wasm/main.rs
+++ b/crates/js-sys/tests/wasm/main.rs
@@ -26,6 +26,7 @@ pub mod MapIterator;
 pub mod Math;
 pub mod Number;
 pub mod Object;
+pub mod Promise;
 pub mod Proxy;
 pub mod RangeError;
 pub mod ReferenceError;