async_hooks: add thisArg to AsyncResource.bind

Semver-major Support setting the `thisArg` for AsyncResource.bind and AsyncResource.prototype.bind. If `thisArg` is not set, then `this` will be set to the `AsyncResource` instance. Fixes: #36051 Signed-off-by: James M Snell <jasnell@gmail.com> PR-URL: #36782 Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com> Reviewed-By: Matteo Collina <matteo.collina@gmail.com> Reviewed-By: Michaël Zasso <targos@protonmail.com> Reviewed-By: Gerhard Stöbich <deb2001-github@yahoo.de>
nodejs · Jan 9, 2021 · 324a6c2 · 324a6c2
1 parent 7dea99b
commit 324a6c2
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Showing 3 changed files with 37 additions and 6 deletions.
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
@@ -730,30 +730,40 @@ class DBQuery extends AsyncResource {
 }
 ```
 
-#### Static method: `AsyncResource.bind(fn[, type])`
+#### Static method: `AsyncResource.bind(fn[, type, [thisArg]])`
 <!-- YAML
 added:
  - v14.8.0
  - v12.19.0
+changes:
+ - version: REPLACEME
+ pr-url: https://github.com/nodejs/node/pull/36782
+ description: Added optional thisArg.
 -->
 
 * `fn` {Function} The function to bind to the current execution context.
 * `type` {string} An optional name to associate with the underlying
  `AsyncResource`.
+* `thisArg` {any}
 
 Binds the given function to the current execution context.
 
 The returned function will have an `asyncResource` property referencing
 the `AsyncResource` to which the function is bound.
 
-#### `asyncResource.bind(fn)`
+#### `asyncResource.bind(fn[, thisArg])`
 <!-- YAML
 added:
  - v14.8.0
  - v12.19.0
+changes:
+ - version: REPLACEME
+ pr-url: https://github.com/nodejs/node/pull/36782
+ description: Added optional thisArg.
 -->
 
 * `fn` {Function} The function to bind to the current `AsyncResource`.
+* `thisArg` {any}
 
 Binds the given function to execute to this `AsyncResource`'s scope.
 

diff --git a/lib/async_hooks.js b/lib/async_hooks.js
@@ -220,10 +220,15 @@ class AsyncResource {
  return this[trigger_async_id_symbol];
  }
 
- bind(fn) {
+ bind(fn, thisArg = this) {
  if (typeof fn !== 'function')
  throw new ERR_INVALID_ARG_TYPE('fn', 'Function', fn);
- const ret = FunctionPrototypeBind(this.runInAsyncScope, this, fn);
+ const ret =
+ FunctionPrototypeBind(
+ this.runInAsyncScope,
+ this,
+ fn,
+ thisArg);
  ObjectDefineProperties(ret, {
  'length': {
  configurable: true,
@@ -241,9 +246,9 @@ class AsyncResource {
  return ret;
  }
 
- static bind(fn, type) {
+ static bind(fn, type, thisArg) {
  type = type || fn.name;
- return (new AsyncResource(type || 'bound-anonymous-fn')).bind(fn);
+ return (new AsyncResource(type || 'bound-anonymous-fn')).bind(fn, thisArg);
  }
 }
 

diff --git a/test/parallel/test-asyncresource-bind.js b/test/parallel/test-asyncresource-bind.js
@@ -33,3 +33,19 @@ setImmediate(() => {
  assert.strictEqual(asyncResource.asyncId(), fn2());
  assert.notStrictEqual(asyncId, fn2());
 });
+
+const foo = {};
+const fn3 = asyncResource.bind(common.mustCall(function() {
+ assert.strictEqual(this, foo);
+}), foo);
+fn3();
+
+const fn4 = asyncResource.bind(common.mustCall(function() {
+ assert.strictEqual(this, asyncResource);
+}));
+fn4();
+
+const fn5 = asyncResource.bind(common.mustCall(function() {
+ assert.strictEqual(this, false);
+}), false);
+fn5();