| <!doctype html> |
| <html lang="en"> |
| <head> |
| <meta charset="utf-8"> |
| <title>XMLHttpRequest: the LOADING state change should only happen once</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <link rel="help" href="https://xhr.spec.whatwg.org/#the-send()-method" data-tested-assertations="following::ol[1]/li[10]/dt[1]"> |
| <link rel="help" href="https://xhr.spec.whatwg.org/#infrastructure-for-the-send()-method" data-tested-assertations="following::dt[7] following::a[contains(@href,'#switch-loading')]/.."> |
| <link rel="help" href="https://xhr.spec.whatwg.org/#switch-loading" data-tested-assertations="following::ol[1]/li[1] following::ol[1]/li[2]"> |
| </head> |
| |
| <div id="log"></div> |
| |
| <script> |
| |
| var test = async_test(); |
| |
| test.step(function() { |
| var client = new XMLHttpRequest(); |
| var countedLoading = 0; |
| |
| client.onreadystatechange = test.step_func(function() { |
| if (client.readyState === 3) { |
| countedLoading += 1; |
| } |
| |
| if (client.readyState === 4) { |
| assert_equals(countedLoading, 1, "LOADING state change may only be emitted once"); |
| |
| test.done(); |
| } |
| }); |
| |
| client.open("GET", "resources/trickle.py?count=10"); // default timeout in trickle.py is 1/2 sec, so this request will take 5 seconds to complete |
| client.send(null); |
| }); |
| </script> |
