| <!doctype html> |
| <meta charset=utf-8> |
| <link rel=help href=https://github.com/whatwg/html/pull/10188#discussion_r1719338657> |
| <title>Adding/changing src attribute does "prepare the script"</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| |
| <body> |
| <script> |
| // The "old" HTML Standard specification text around `src` attribute mutation |
| // for non-parser-inserted scripts *ONLY* "prepared"/run the script iff the src |
| // attribute "previously had no such attribute". This changed in |
| // https://github.com/whatwg/html/pull/10188 to align with a majority of |
| // browsers. This test ensures that `src` mutations on these kinds of scripts |
| // *where a previous valid `src` attribute existed* do indeed "prepare" the |
| // script. |
| promise_test(async () => { |
| window.didExecute = false; |
| |
| const script = document.createElement('script'); |
| // Invalid type, so the script won't execute upon insertion. |
| script.type = 'invalid'; |
| script.src = 'resources/flag-setter.js'; |
| document.body.append(script); |
| assert_false(window.didExecute); |
| |
| // Make script valid, but don't immediately execute it. |
| script.type = ''; |
| |
| const scriptPromise = new Promise(resolve => { |
| script.onload = resolve; |
| }); |
| |
| // Mutating the `src` attribute, which has an existing valid value, triggers |
| // the "prepare a script" algorithm via the post-connection steps. |
| script.src = 'resources/flag-setter.js?different'; |
| |
| await scriptPromise; |
| assert_true(window.didExecute); |
| }, "Mutating `src` attribute from an already-valid value does 'prepare' the script"); |
| </script> |
| </body> |
