async_hooks: use resource objects for Promises

Use `PromiseWrap` resource objects whose lifetimes are tied to
the `Promise` instances themselves to track promises, and have
a `.promise` getter that points to the `Promise` and a `.parent`
property that points to the parent Promise’s resource object,
if there is any.

The properties are implemented as getters for internal fields
rather than normal properties in the hope that it helps keep
performance for the common case that async_hooks users will
often not inspect them.

PR-URL: https://github.com/nodejs/node/pull/13452
Reviewed-By: Andreas Madsen <amwebdk@gmail.com>
Reviewed-By: Trevor Norris <trev.norris@gmail.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/test/parallel/test-async-hooks-promise.js b/test/parallel/test-async-hooks-promise.js
new file mode 100644
index 0000000000..ea5e59d319
--- /dev/null
+++ b/test/parallel/test-async-hooks-promise.js
@@ -0,0 +1,23 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const async_hooks = require('async_hooks');
+
+const initCalls = [];
+
+async_hooks.createHook({
+  init: common.mustCall((id, type, triggerId, resource) => {
+    assert.strictEqual(type, 'PROMISE');
+    initCalls.push({id, triggerId, resource});
+  }, 2)
+}).enable();
+
+const a = Promise.resolve(42);
+const b = a.then(common.mustCall());
+
+assert.strictEqual(initCalls[0].triggerId, 1);
+assert.strictEqual(initCalls[0].resource.parentId, undefined);
+assert.strictEqual(initCalls[0].resource.promise, a);
+assert.strictEqual(initCalls[1].triggerId, initCalls[0].id);
+assert.strictEqual(initCalls[1].resource.parentId, initCalls[0].id);
+assert.strictEqual(initCalls[1].resource.promise, b);