| // META: script=performanceobservers.js |
| |
| async_test(function (t) { |
| const observer = new PerformanceObserver( |
| t.step_func(function (entryList) { |
| checkEntries(entryList.getEntries(), |
| [{ entryType: "mark", name: "early"}]); |
| observer.disconnect(); |
| t.done(); |
| }) |
| ); |
| performance.mark("early"); |
| // This call will not trigger anything. |
| observer.observe({type: "mark"}); |
| // This call should override the previous call and detect the early mark. |
| observer.observe({type: "mark", buffered: true}); |
| }, "Two calls of observe() with the same 'type' cause override."); |