| <!DOCTYPE html> |
| <head> |
| <title>Performance Paint Timing Test: FCP due to canvas</title> |
| </head> |
| <body> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <canvas id="canvas" width="200" height="200" ></canvas> |
| |
| <script> |
| async_test(function (t) { |
| const canvas = document.getElementById("canvas"); |
| const context = canvas.getContext("2d"); |
| context.beginPath(); |
| context.moveTo(0,0); |
| context.lineTo(300,150); |
| context.stroke(); |
| function testPaintEntries() { |
| const bufferedEntries = performance.getEntriesByType('paint'); |
| if (bufferedEntries.length < 2) { |
| t.step_timeout(function() { |
| testPaintEntries(); |
| }, 20); |
| return; |
| } |
| t.step(function() { |
| assert_equals(bufferedEntries.length, 2, "There should be two paint timing instances."); |
| assert_equals(bufferedEntries[0].entryType, "paint"); |
| assert_equals(bufferedEntries[0].name, "first-paint"); |
| assert_equals(bufferedEntries[1].entryType, "paint"); |
| assert_equals(bufferedEntries[1].name, "first-contentful-paint"); |
| t.done(); |
| }); |
| }; |
| t.step(function() { |
| testPaintEntries(); |
| }); |
| }, "First contentful paint fires due to canvas render."); |
| </script> |
| </body> |
| </html> |
