test: move common.onGC to individual module

Incrementally making `require('../common')` less of a monolith.
Move the `common.onGC()` utility to a separate standalone module
that is only imported when it's actually needed.

PR-URL: https://github.com/nodejs/node/pull/22446
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Weijia Wang <starkwang@126.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/test/common/ongc.js b/test/common/ongc.js
new file mode 100644
index 0000000000..d8e27beb8f
--- /dev/null
+++ b/test/common/ongc.js
@@ -0,0 +1,32 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const gcTrackerMap = new WeakMap();
+const gcTrackerTag = 'NODE_TEST_COMMON_GC_TRACKER';
+
+function onGC(obj, gcListener) {
+  const async_hooks = require('async_hooks');
+
+  const onGcAsyncHook = async_hooks.createHook({
+    init: common.mustCallAtLeast(function(id, type) {
+      if (this.trackedId === undefined) {
+        assert.strictEqual(type, gcTrackerTag);
+        this.trackedId = id;
+      }
+    }),
+    destroy(id) {
+      assert.notStrictEqual(this.trackedId, -1);
+      if (id === this.trackedId) {
+        this.gcListener.ongc();
+        onGcAsyncHook.disable();
+      }
+    }
+  }).enable();
+  onGcAsyncHook.gcListener = gcListener;
+
+  gcTrackerMap.set(obj, new async_hooks.AsyncResource(gcTrackerTag));
+  obj = null;
+}
+
+module.exports = onGC;