fix(napi-derive-backend): do not unwrap Option value in object getter if the type of field is Option<T>

crates/backend/src/codegen/struct.rs

@@ -239,17 +239,37 @@ impl NapiStruct {
     for field in self.fields.iter() {
       let field_js_name = &field.js_name;
       let ty = &field.ty;
-
+      let is_optional_field = if let syn::Type::Path(syn::TypePath {
+        path: syn::Path { segments, .. },
+        ..
+      }) = &ty
+      {
+        if let Some(last_path) = segments.last() {
+          last_path.ident.to_string() == "Option"
+        } else {
+          false
+        }
+      } else {
+        false
+      };
       match &field.name {
         syn::Member::Named(ident) => {
           field_destructions.push(quote! { #ident });
           obj_field_setters.push(quote! { obj.set(#field_js_name, #ident)?; });
-          obj_field_getters.push(quote! { let #ident: #ty = obj.get(#field_js_name)?.expect(&format!("Field {} should exist", #field_js_name)); });
+          if is_optional_field {
+            obj_field_getters.push(quote! { let #ident: #ty = obj.get(#field_js_name)?; });
+          } else {
+            obj_field_getters.push(quote! { let #ident: #ty = obj.get(#field_js_name)?.expect(&format!("Field {} should exist", #field_js_name)); });
+          }
         }
         syn::Member::Unnamed(i) => {
           field_destructions.push(quote! { arg#i });
           obj_field_setters.push(quote! { obj.set(#field_js_name, arg#1)?; });
-          obj_field_getters.push(quote! { let arg#i: #ty = obj.get(#field_js_name)?.expect(&format!("Field {} should exist", #field_js_name)); });
+          if is_optional_field {
+            obj_field_getters.push(quote! { let arg#i: #ty = obj.get(#field_js_name)?; });
+          } else {
+            obj_field_getters.push(quote! { let arg#i: #ty = obj.get(#field_js_name)?.expect(&format!("Field {} should exist", #field_js_name)); });
+          }
         }
       }
     }

crates/napi/src/bindgen_runtime/js_values/object.rs

@@ -35,7 +35,7 @@ impl Object {
 
       let ty = type_of!(self.0.env, ret)?;
 
-      Ok(if ty == ValueType::Undefined {
+      Ok(if ty == ValueType::Undefined || ty == ValueType::Null {
         None
       } else {
         Some(V::from_napi_value(self.0.env, ret)?)

examples/napi/__test__/typegen.spec.ts.md

@@ -73,6 +73,11 @@ Generated by [AVA](https://avajs.dev).
     export function getGlobal(): typeof global␊
     export function getUndefined(): void␊
     export function getNull(): JsNull␊
+    export interface AllOptionalObject {␊
+      name?: string | undefined | null␊
+      age?: number | undefined | null␊
+    }␊
+    export function receiveAllOptionalObject(obj?: AllOptionalObject | undefined | null): void␊
     export function asyncPlus100(p: Promise<number>): Promise<number>␊
     /** This is an interface for package.json */␊
     export interface PackageJson {␊

examples/napi/__test__/values.spec.ts

@@ -59,6 +59,7 @@ import {
   convertU32Array,
   createExternalTypedArray,
   mutateTypedArray,
+  receiveAllOptionalObject,
 } from '../'
 
 test('export const', (t) => {
@@ -202,6 +203,11 @@ test('function ts type override', (t) => {
   t.deepEqual(tsRename({ foo: 1, bar: 2, baz: 2 }), ['foo', 'bar', 'baz'])
 })
 
+test('option object', (t) => {
+  t.notThrows(() => receiveAllOptionalObject())
+  t.notThrows(() => receiveAllOptionalObject({}))
+})
+
 test('serde-json', (t) => {
   const packageJson = readPackageJson()
   t.is(packageJson.name, 'napi-rs')

examples/napi/index.d.ts

@@ -63,6 +63,11 @@ export function createObj(): object
 export function getGlobal(): typeof global
 export function getUndefined(): void
 export function getNull(): JsNull
+export interface AllOptionalObject {
+  name?: string | undefined | null
+  age?: number | undefined | null
+}
+export function receiveAllOptionalObject(obj?: AllOptionalObject | undefined | null): void
 export function asyncPlus100(p: Promise<number>): Promise<number>
 /** This is an interface for package.json */
 export interface PackageJson {

examples/napi/src/object.rs

@@ -27,3 +27,18 @@ fn get_undefined(env: Env) -> Result<JsUndefined> {
 fn get_null(env: Env) -> Result<JsNull> {
   env.get_null()
 }
+
+#[napi(object)]
+struct AllOptionalObject {
+  pub name: Option<String>,
+  pub age: Option<u32>,
+}
+
+#[napi]
+fn receive_all_optional_object(obj: Option<AllOptionalObject>) -> Result<()> {
+  if !obj.is_none() {
+    assert!(obj.as_ref().unwrap().name.is_none());
+    assert!(obj.as_ref().unwrap().age.is_none());
+  }
+  Ok(())
+}