Function onGC

test/common/gc.js:19–41

* Installs a garbage collection listener for the specified object. * Uses async_hooks for GC tracking, which may affect test functionality. * A full setImmediate() invocation passes between a global.gc() call and the listener being invoked. * @param {object} obj - The target object to track for g

(obj, gcListener)

 * @param {Function} gcListener.ongc - The function to call when the target object is garbage collected.
 */
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;
}

/**
 * Repeatedly triggers garbage collection until a specified condition is met or a maximum number of attempts is reached.