From 530359421cea307d85d429383e9d57cd275b47d6 Mon Sep 17 00:00:00 2001
From: LongYinan <lynweklm@gmail.com>
Date: Thu, 24 Dec 2020 11:53:23 +0800
Subject: [PATCH] refactor(napi): create_buffer_with_borrowed_data now accepted
 raw ptr

---
 napi/src/env.rs                     | 18 ++++++-----
 test_module/__test__/buffer.spec.ts | 14 +++++++++
 test_module/src/buffer.rs           | 47 ++++++++++++++++++++++++++++-
 3 files changed, 70 insertions(+), 9 deletions(-)

diff --git a/napi/src/env.rs b/napi/src/env.rs
index 2a272b57..2588a838 100644
--- a/napi/src/env.rs
+++ b/napi/src/env.rs
@@ -320,20 +320,19 @@ impl Env {
   /// Provided `finalize_callback` will be called when `Buffer` got dropped.
   pub unsafe fn create_buffer_with_borrowed_data<Hint, Finalize>(
     &self,
-    data: &[u8],
+    data: *const u8,
+    length: usize,
     hint: Hint,
     finalize_callback: Option<Finalize>,
   ) -> Result<JsBufferValue>
   where
-    Finalize: FnOnce(Env, Hint),
+    Finalize: FnOnce(Hint, Env),
   {
-    let length = data.len();
     let mut raw_value = ptr::null_mut();
-    let data_ptr = data.as_ptr();
     check_status!(sys::napi_create_external_buffer(
       self.0,
       length,
-      data_ptr as *mut c_void,
+      data as *mut c_void,
       Some(
         raw_finalize_with_custom_callback::<Hint, Finalize>
           as unsafe extern "C" fn(
@@ -351,7 +350,7 @@ impl Env {
         value: raw_value,
         value_type: ValueType::Object,
       }),
-      mem::ManuallyDrop::new(Vec::from_raw_parts(data_ptr as *mut u8, length, length)),
+      mem::ManuallyDrop::new(Vec::from_raw_parts(data as *mut u8, length, length)),
     ))
   }
 
@@ -1065,6 +1064,9 @@ impl Env {
   }
 }
 
+/// This function could be used for `create_buffer_with_borrowed_data` and want do noting when Buffer finalized.
+pub fn noop_finalize<Hint>(_hint: Hint, _env: Env) {}
+
 unsafe extern "C" fn drop_buffer(
   _env: sys::napi_env,
   finalize_data: *mut c_void,
@@ -1125,10 +1127,10 @@ unsafe extern "C" fn raw_finalize_with_custom_callback<Hint, Finalize>(
   _finalize_data: *mut c_void,
   finalize_hint: *mut c_void,
 ) where
-  Finalize: FnOnce(Env, Hint),
+  Finalize: FnOnce(Hint, Env),
 {
   let (hint, maybe_callback) = *Box::from_raw(finalize_hint as *mut (Hint, Option<Finalize>));
   if let Some(callback) = maybe_callback {
-    callback(Env::from_raw(env), hint);
+    callback(hint, Env::from_raw(env));
   };
 }
diff --git a/test_module/__test__/buffer.spec.ts b/test_module/__test__/buffer.spec.ts
index 21ebe469..5f5d4865 100644
--- a/test_module/__test__/buffer.spec.ts
+++ b/test_module/__test__/buffer.spec.ts
@@ -18,3 +18,17 @@ test('should copy', (t) => {
   t.deepEqual(copyBuffer, fixture)
   t.not(fixture, copyBuffer)
 })
+
+test('should create borrowed buffer with noop finalize', (t) => {
+  t.deepEqual(
+    bindings.createBorrowedBufferWithNoopFinalize(),
+    Buffer.from([1, 2, 3]),
+  )
+})
+
+test('should create borrowed buffer with finalize', (t) => {
+  t.deepEqual(
+    bindings.createBorrowedBufferWithFinalize(),
+    Buffer.from([1, 2, 3]),
+  )
+})
diff --git a/test_module/src/buffer.rs b/test_module/src/buffer.rs
index d55214e6..0b7dd157 100644
--- a/test_module/src/buffer.rs
+++ b/test_module/src/buffer.rs
@@ -1,6 +1,10 @@
+use std::mem::ManuallyDrop;
 use std::str;
 
-use napi::{CallContext, Error, JsBuffer, JsNumber, JsObject, JsString, Result, Status};
+use napi::{
+  noop_finalize, CallContext, ContextlessResult, Env, Error, JsBuffer, JsNumber, JsObject,
+  JsString, Result, Status,
+};
 
 #[js_function(1)]
 pub fn get_buffer_length(ctx: CallContext) -> Result<JsNumber> {
@@ -22,9 +26,50 @@ pub fn copy_buffer(ctx: CallContext) -> Result<JsBuffer> {
   ctx.env.create_buffer_copy(buffer).map(|b| b.into_raw())
 }
 
+#[contextless_function]
+pub fn create_borrowed_buffer_with_noop_finalize(env: Env) -> ContextlessResult<JsBuffer> {
+  let data = vec![1, 2, 3];
+  let data_ptr = data.as_ptr();
+  let length = data.len();
+  let manually_drop = ManuallyDrop::new(data);
+
+  unsafe {
+    env.create_buffer_with_borrowed_data(data_ptr, length, manually_drop, Some(noop_finalize))
+  }
+  .map(|b| Some(b.into_raw()))
+}
+
+#[contextless_function]
+pub fn create_borrowed_buffer_with_finalize(env: Env) -> ContextlessResult<JsBuffer> {
+  let data = vec![1, 2, 3];
+  let data_ptr = data.as_ptr();
+  let length = data.len();
+  let manually_drop = ManuallyDrop::new(data);
+
+  unsafe {
+    env.create_buffer_with_borrowed_data(
+      data_ptr,
+      length,
+      manually_drop,
+      Some(|mut hint: ManuallyDrop<Vec<u8>>, _| {
+        ManuallyDrop::drop(&mut hint);
+      }),
+    )
+  }
+  .map(|b| Some(b.into_raw()))
+}
+
 pub fn register_js(exports: &mut JsObject) -> Result<()> {
   exports.create_named_method("getBufferLength", get_buffer_length)?;
   exports.create_named_method("bufferToString", buffer_to_string)?;
   exports.create_named_method("copyBuffer", copy_buffer)?;
+  exports.create_named_method(
+    "createBorrowedBufferWithNoopFinalize",
+    create_borrowed_buffer_with_noop_finalize,
+  )?;
+  exports.create_named_method(
+    "createBorrowedBufferWithFinalize",
+    create_borrowed_buffer_with_finalize,
+  )?;
   Ok(())
 }