Merge pull request #1150 from napi-rs/into-reference

feat(napi): support return Reference on class instance

crates/backend/src/codegen/struct.rs

@@ -216,19 +216,50 @@ impl NapiStruct {
 
   fn gen_to_napi_value_ctor_impl_for_non_default_constructor_struct(&self) -> TokenStream {
     let name = &self.name;
-    let js_name_str = format!("{}\0", &self.js_name);
+    let js_name_raw = &self.js_name;
+    let js_name_str = format!("{}\0", js_name_raw);
     quote! {
       impl napi::bindgen_prelude::ToNapiValue for #name {
         unsafe fn to_napi_value(
-          env: napi::sys::napi_env, val: #name
+          env: napi::sys::napi_env,
+          val: #name
         ) -> napi::Result<napi::bindgen_prelude::sys::napi_value> {
           if let Some(ctor_ref) = napi::bindgen_prelude::get_class_constructor(#js_name_str) {
-            let mut ctor = std::ptr::null_mut();
+            let wrapped_value = Box::into_raw(Box::new(val)) as *mut std::ffi::c_void;
+            #name::new_instance(env, wrapped_value, ctor_ref)
+          } else {
+            Err(napi::bindgen_prelude::Error::new(
+              napi::bindgen_prelude::Status::InvalidArg, format!("Failed to get constructor of class `{}`", #js_name_raw))
+            )
+          }
+        }
+      }
 
+      impl #name {
+        pub fn into_reference(val: #name, env: napi::Env) -> napi::Result<napi::bindgen_prelude::Reference<#name>> {
+          if let Some(ctor_ref) = napi::bindgen_prelude::get_class_constructor(#js_name_str) {
+            unsafe {
+              let wrapped_value = Box::into_raw(Box::new(val)) as *mut std::ffi::c_void;
+              #name::new_instance(env.raw(), wrapped_value, ctor_ref)?;
+              napi::bindgen_prelude::Reference::<#name>::from_value_ptr(wrapped_value, env.raw())
+            }
+          } else {
+            Err(napi::bindgen_prelude::Error::new(
+              napi::bindgen_prelude::Status::InvalidArg, format!("Failed to get constructor of class `{}`", #js_name_raw))
+            )
+          }
+        }
+
+        unsafe fn new_instance(
+          env: napi::sys::napi_env,
+          wrapped_value: *mut std::ffi::c_void,
+          ctor_ref: napi::sys::napi_ref,
+        ) -> napi::Result<napi::bindgen_prelude::sys::napi_value> {
+          let mut ctor = std::ptr::null_mut();
           napi::check_status!(
             napi::sys::napi_get_reference_value(env, ctor_ref, &mut ctor),
             "Failed to get constructor of class `{}`",
-              #js_name_str
+            #js_name_raw
           )?;
 
           let mut result = std::ptr::null_mut();
@@ -236,9 +267,8 @@ impl NapiStruct {
           napi::check_status!(
             napi::sys::napi_new_instance(env, ctor, 0, std::ptr::null_mut(), &mut result),
             "Failed to construct class `{}`",
-              #js_name_str
+            #js_name_raw
           )?;
-            let wrapped_value = Box::into_raw(Box::new(val)) as *mut std::ffi::c_void;
           let mut object_ref = std::ptr::null_mut();
           let initial_finalize: Box<dyn FnOnce()> = Box::new(|| {});
           let finalize_callbacks_ptr = std::rc::Rc::into_raw(std::rc::Rc::new(std::cell::Cell::new(Box::into_raw(initial_finalize))));
@@ -252,16 +282,11 @@ impl NapiStruct {
               &mut object_ref,
             ),
             "Failed to wrap native object of class `{}`",
-              #js_name_str
+            #js_name_raw
           )?;
           napi::bindgen_prelude::Reference::<#name>::add_ref(wrapped_value, (wrapped_value, object_ref, finalize_callbacks_ptr));
           napi::bindgen_prelude::___CALL_FROM_FACTORY.with(|inner| inner.store(false, std::sync::atomic::Ordering::Relaxed));
           Ok(result)
-          } else {
-            Err(napi::bindgen_prelude::Error::new(
-              napi::bindgen_prelude::Status::InvalidArg, format!("Failed to get constructor of class `{}`", #js_name_str))
-            )
-          }
         }
       }
     }

crates/backend/src/typegen.rs

@@ -278,6 +278,15 @@ pub fn ty_to_ts_type(ty: &Type, is_return_ty: bool, is_struct_field: bool) -> (S
               Some(("Promise<unknown>".to_owned(), false))
             }
           });
+        } else if rust_ty == "Reference" {
+          ts_ty = r#struct::TASK_STRUCTS.with(|t| {
+            let (output_type, _) = args.first().unwrap().to_owned();
+            if let Some(o) = t.borrow().get(&output_type) {
+              Some((o.to_owned(), false))
+            } else {
+              Some((output_type, false))
+            }
+          });
         } else if let Some(&known_ty) = KNOWN_TYPES.get(rust_ty.as_str()) {
           if known_ty.contains("{}") {
             ts_ty = Some((

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

@@ -4,7 +4,7 @@ use std::ffi::c_void;
 use std::ops::{Deref, DerefMut};
 use std::rc::Rc;
 
-use crate::{check_status, Env, Error, Result, Status};
+use crate::{bindgen_runtime::ToNapiValue, check_status, Env, Error, Result, Status};
 
 type RefInformation = (
   *mut c_void,
@@ -20,7 +20,7 @@ thread_local! {
 ///
 /// Create a `reference` from `Class` instance.
 /// Unref the `Reference` when the `Reference` is dropped.
-pub struct Reference<T> {
+pub struct Reference<T: 'static> {
   raw: *mut T,
   napi_ref: crate::sys::napi_ref,
   env: *mut c_void,
@@ -42,7 +42,7 @@ impl<T> Drop for Reference<T> {
   }
 }
 
-impl<T> Reference<T> {
+impl<T: 'static> Reference<T> {
   #[doc(hidden)]
   pub fn add_ref(t: *mut c_void, value: RefInformation) {
     REFERENCE_MAP.with(|map| {
@@ -78,6 +78,17 @@ impl<T> Reference<T> {
   }
 }
 
+impl<T: 'static> ToNapiValue for Reference<T> {
+  unsafe fn to_napi_value(env: crate::sys::napi_env, val: Self) -> Result<crate::sys::napi_value> {
+    let mut result = std::ptr::null_mut();
+    check_status!(
+      unsafe { crate::sys::napi_get_reference_value(env, val.napi_ref, &mut result) },
+      "Failed to get reference value"
+    )?;
+    Ok(result)
+  }
+}
+
 impl<T: 'static> Reference<T> {
   pub fn clone(&self, env: Env) -> Result<Self> {
     let mut ref_count = 0;
@@ -114,7 +125,7 @@ impl<T: 'static> Reference<T> {
   }
 }
 
-impl<T> Deref for Reference<T> {
+impl<T: 'static> Deref for Reference<T> {
   type Target = T;
 
   fn deref(&self) -> &Self::Target {
@@ -122,7 +133,7 @@ impl<T> Deref for Reference<T> {
   }
 }
 
-impl<T> DerefMut for Reference<T> {
+impl<T: 'static> DerefMut for Reference<T> {
   fn deref_mut(&mut self) -> &mut Self::Target {
     unsafe { Box::leak(Box::from_raw(self.raw)) }
   }
@@ -131,7 +142,7 @@ impl<T> DerefMut for Reference<T> {
 /// ### Experimental feature
 ///
 /// Create a `SharedReference` from an existed `Reference`.
-pub struct SharedReference<T, S> {
+pub struct SharedReference<T: 'static, S: 'static> {
   raw: *mut S,
   owner: Reference<T>,
 }
@@ -168,7 +179,18 @@ impl<T: 'static, S: 'static> SharedReference<T, S> {
   }
 }
 
-impl<T, S> Deref for SharedReference<T, S> {
+impl<T: 'static, S: 'static> ToNapiValue for SharedReference<T, S> {
+  unsafe fn to_napi_value(env: crate::sys::napi_env, val: Self) -> Result<crate::sys::napi_value> {
+    let mut result = std::ptr::null_mut();
+    check_status!(
+      unsafe { crate::sys::napi_get_reference_value(env, val.owner.napi_ref, &mut result) },
+      "Failed to get reference value"
+    )?;
+    Ok(result)
+  }
+}
+
+impl<T: 'static, S: 'static> Deref for SharedReference<T, S> {
   type Target = S;
 
   fn deref(&self) -> &Self::Target {
@@ -176,7 +198,7 @@ impl<T, S> Deref for SharedReference<T, S> {
   }
 }
 
-impl<T, S> DerefMut for SharedReference<T, S> {
+impl<T: 'static, S: 'static> DerefMut for SharedReference<T, S> {
   fn deref_mut(&mut self) -> &mut Self::Target {
     unsafe { Box::leak(Box::from_raw(self.raw)) }
   }

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

@@ -271,6 +271,15 @@ Generated by [AVA](https://avajs.dev).
     export class JsRemote {␊
       name(): string␊
     }␊
+    export type CSSRuleList = CssRuleList␊
+    export class CssRuleList {␊
+      getRules(): Array<string>␊
+    }␊
+    export type CSSStyleSheet = CssStyleSheet␊
+    export class CssStyleSheet {␊
+      constructor(rules: Array<string>)␊
+      get rules(): CssRuleList␊
+    }␊
     export namespace xxh3 {␊
       export const ALIGNMENT: number␊
       export function xxh3_64(input: Buffer): bigint␊

examples/napi/__test__/values.spec.ts

@@ -90,6 +90,7 @@ import {
   chronoDateAdd1Minute,
   bufferPassThrough,
   JsRepo,
+  CssStyleSheet,
   asyncReduceBuffer,
   callbackReturnPromise,
 } from '../'
@@ -199,6 +200,13 @@ test('should be able to create object reference and shared reference', (t) => {
   t.is(repo.remote().name(), 'origin')
 })
 
+test('should be able to into_reference', (t) => {
+  const rules = ['body: { color: red }', 'div: { color: blue }']
+  const sheet = new CssStyleSheet(rules)
+  t.is(sheet.rules, sheet.rules)
+  t.deepEqual(sheet.rules.getRules(), rules)
+})
+
 test('callback', (t) => {
   getCwd((cwd) => {
     t.is(cwd, process.cwd())

examples/napi/index.d.ts

@@ -261,6 +261,15 @@ export class JsRepo {
 export class JsRemote {
   name(): string
 }
+export type CSSRuleList = CssRuleList
+export class CssRuleList {
+  getRules(): Array<string>
+}
+export type CSSStyleSheet = CssStyleSheet
+export class CssStyleSheet {
+  constructor(rules: Array<string>)
+  get rules(): CssRuleList
+}
 export namespace xxh3 {
   export const ALIGNMENT: number
   export function xxh3_64(input: Buffer): bigint

examples/napi/src/reference.rs

@@ -1,3 +1,5 @@
+use std::{cell::RefCell, rc::Rc};
+
 use napi::bindgen_prelude::*;
 
 pub struct Repository {
@@ -54,3 +56,46 @@ impl JsRemote {
     self.inner.name()
   }
 }
+
+struct OwnedStyleSheet {
+  rules: Vec<String>,
+}
+
+#[napi]
+pub struct CSSRuleList {
+  owned: Rc<RefCell<OwnedStyleSheet>>,
+}
+
+#[napi]
+impl CSSRuleList {
+  #[napi]
+  pub fn get_rules(&self) -> Vec<String> {
+    self.owned.borrow().rules.to_vec()
+  }
+}
+
+#[napi]
+pub struct CSSStyleSheet {
+  inner: Rc<RefCell<OwnedStyleSheet>>,
+  rules: Reference<CSSRuleList>,
+}
+
+#[napi]
+impl CSSStyleSheet {
+  #[napi(constructor)]
+  pub fn new(env: Env, rules: Vec<String>) -> Result<Self> {
+    let inner = Rc::new(RefCell::new(OwnedStyleSheet { rules }));
+    let rules = CSSRuleList::into_reference(
+      CSSRuleList {
+        owned: inner.clone(),
+      },
+      env,
+    )?;
+    Ok(CSSStyleSheet { inner, rules })
+  }
+
+  #[napi(getter)]
+  pub fn rules(&self, env: Env) -> Result<Reference<CSSRuleList>> {
+    self.rules.clone(env)
+  }
+}