From 0aa7cd3d325f1e798885a4048c8286c5688b54e9 Mon Sep 17 00:00:00 2001
From: h-a-n-a <andywangsy@gmail.com>
Date: Sat, 11 Dec 2021 13:42:46 +0800
Subject: [PATCH] feat(napi): support external deref/derefMut

---
 .../src/bindgen_runtime/js_values/external.rs | 19 ++++++++++++++++++-
 examples/napi/src/external.rs                 |  4 ++--
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/crates/napi/src/bindgen_runtime/js_values/external.rs b/crates/napi/src/bindgen_runtime/js_values/external.rs
index 66f790ca..47ce4ef2 100644
--- a/crates/napi/src/bindgen_runtime/js_values/external.rs
+++ b/crates/napi/src/bindgen_runtime/js_values/external.rs
@@ -1,4 +1,7 @@
-use std::any::TypeId;
+use std::{
+  any::TypeId,
+  ops::{Deref, DerefMut},
+};
 
 use crate::{check_status, Error, Status, TaggedObject};
 
@@ -73,6 +76,20 @@ impl<T: 'static> AsMut<T> for External<T> {
   }
 }
 
+impl<T: 'static> Deref for External<T> {
+  type Target = T;
+
+  fn deref(&self) -> &Self::Target {
+    self.as_ref()
+  }
+}
+
+impl<T: 'static> DerefMut for External<T> {
+  fn deref_mut(&mut self) -> &mut Self::Target {
+    self.as_mut()
+  }
+}
+
 impl<T: 'static> ToNapiValue for External<T> {
   unsafe fn to_napi_value(
     env: napi_sys::napi_env,
diff --git a/examples/napi/src/external.rs b/examples/napi/src/external.rs
index 699a8f80..581b2710 100644
--- a/examples/napi/src/external.rs
+++ b/examples/napi/src/external.rs
@@ -12,10 +12,10 @@ pub fn create_external_string(content: String) -> External<String> {
 
 #[napi]
 pub fn get_external(external: External<u32>) -> u32 {
-  *external.as_ref()
+  *external
 }
 
 #[napi]
 pub fn mutate_external(mut external: External<u32>, new_val: u32) {
-  *external.as_mut() = new_val;
+  *external = new_val;
 }