| <!DOCTYPE html> |
| <head> |
| <title>Below-viewport loading=lazy images do not block the window load event |
| when scrolled into viewport</title> |
| <link rel="author" title="Rob Buis" href="mailto:rbuis@igalia.com"> |
| <link rel="author" title="Dom Farolino" href="mailto:dom@chromium.org"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script src="../resources/common.js"></script> |
| </head> |
| |
| <body> |
| <!-- When this image loads, we will scroll the below-viewport loading=lazy |
| images into the viewport. This happens before the window load event is |
| fired --> |
| <img id="scroll_trigger" |
| src="resources/image.png?scroll-trigger&pipe=trickle(d1)" |
| onload="scroll_trigger_img.resolve();" onerror="scroll_trigger_img.reject();"> |
| <!-- This image blocks the window load event for 2 seconds --> |
| <img src="resources/image.png?window-load-blocking&pipe=trickle(d2)"> |
| |
| <div style="height:1000vh"></div> |
| <!-- These images must load because they intersect the viewport, but they must |
| not block the window load event, because they are loading=lazy --> |
| <img id="visible" |
| src="resources/image.png?visible&pipe=trickle(d3)" loading="lazy" |
| onload="visible_img.resolve();" onerror="visible_img.reject();"> |
| <img id="visibility_hidden" style="visibility:hidden;" |
| src="resources/image.png?visibility_hidden&pipe=trickle(d3)" loading="lazy" |
| onload="visibility_hidden_img.resolve();" onerror="visibility_hidden_img.reject();"> |
| </body> |
| |
| <script> |
| const scroll_trigger_img = new ElementLoadPromise("visible"); |
| const visible_img = new ElementLoadPromise("visible"); |
| const visibility_hidden_img = new ElementLoadPromise("visibility_hidden"); |
| |
| async_test(t => { |
| let has_window_loaded = false; |
| |
| scroll_trigger_img.promise |
| .then(t.step_func(() => { |
| assert_false(has_window_loaded, |
| "The scroll_trigger image should load before the window " + |
| "load event fires"); |
| visibility_hidden_img.element().scrollIntoView(); |
| })) |
| .catch(t.unreached_func("The scroll_trigger image should load")); |
| |
| window.addEventListener("load", t.step_func(() => { |
| has_window_loaded = true; |
| })); |
| |
| Promise.all([visible_img.promise, visibility_hidden_img.promise]) |
| .then(t.step_func_done(() => { |
| assert_true(has_window_loaded, |
| "The window load event should fire before the " + |
| "below-viewport loading=lazy images load"); |
| assert_true(visible_img.element().complete, |
| "The below-viewport loading=lazy visible image is complete"); |
| assert_true(visibility_hidden_img.element().complete, |
| "The below-viewport loading=lazy visibility:hidden image is complete"); |
| })) |
| .catch(t.unreached_func("The images should load successfully")); |
| |
| }, "Below-viewport loading=lazy images do not block the window load event when " + |
| "scrolled into viewport"); |
| </script> |
| |
