test: add test for async contexts in PerformanceObserver

ZauberNerd · targos · commit 0f749a35ec83 · 2020-12-21T16:49:22.000+01:00
This test proves that the PerformanceObserver callback gets called with the async context of the callsite of performance.mark()/measure() and therefore AsyncLocalStorage can be used inside a PerformanceObserver. PR: #36343 PR-URL: #36343 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Anna Henningsen <anna@addaleax.net> Reviewed-By: Rich Trott <rtrott@gmail.com>
diff --git a/test/parallel/test-performanceobserver-asynccontext.js b/test/parallel/test-performanceobserver-asynccontext.js
@@ -0,0 +1,37 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const {
+  performance,
+  PerformanceObserver,
+} = require('perf_hooks');
+const {
+  executionAsyncId,
+  triggerAsyncId,
+  executionAsyncResource,
+} = require('async_hooks');
+
+// Test Non-Buffered PerformanceObserver retains async context
+{
+  const observer =
+    new PerformanceObserver(common.mustCall(callback));
+
+  const initialAsyncId = executionAsyncId();
+  let asyncIdInTimeout;
+  let asyncResourceInTimeout;
+
+  function callback(list) {
+    assert.strictEqual(triggerAsyncId(), initialAsyncId);
+    assert.strictEqual(executionAsyncId(), asyncIdInTimeout);
+    assert.strictEqual(executionAsyncResource(), asyncResourceInTimeout);
+    observer.disconnect();
+  }
+  observer.observe({ entryTypes: ['mark'] });
+
+  setTimeout(() => {
+    asyncIdInTimeout = executionAsyncId();
+    asyncResourceInTimeout = executionAsyncResource();
+    performance.mark('test1');
+  }, 0);
+}
