{"action":"created","issue":{"url":"https://api.github.com/repos/whatwg/html/issues/655","repository_url":"https://api.github.com/repos/whatwg/html","labels_url":"https://api.github.com/repos/whatwg/html/issues/655/labels{/name}","comments_url":"https://api.github.com/repos/whatwg/html/issues/655/comments","events_url":"https://api.github.com/repos/whatwg/html/issues/655/events","html_url":"https://github.com/whatwg/html/issues/655","id":132231148,"number":655,"title":"createPattern says it never returns null, but it can return null","user":{"login":"bzbarsky","id":1457979,"avatar_url":"https://avatars.githubusercontent.com/u/1457979?v=3","gravatar_id":"","url":"https://api.github.com/users/bzbarsky","html_url":"https://github.com/bzbarsky","followers_url":"https://api.github.com/users/bzbarsky/followers","following_url":"https://api.github.com/users/bzbarsky/following{/other_user}","gists_url":"https://api.github.com/users/bzbarsky/gists{/gist_id}","starred_url":"https://api.github.com/users/bzbarsky/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/bzbarsky/subscriptions","organizations_url":"https://api.github.com/users/bzbarsky/orgs","repos_url":"https://api.github.com/users/bzbarsky/repos","events_url":"https://api.github.com/users/bzbarsky/events{/privacy}","received_events_url":"https://api.github.com/users/bzbarsky/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":1,"created_at":"2016-02-08T19:08:48Z","updated_at":"2016-02-08T20:46:04Z","closed_at":null,"body":"IDL:\r\n\r\n    CanvasPattern createPattern(CanvasImageSource image, [TreatNullAs=EmptyString] DOMString repetition);\r\n\r\nProse at https://html.spec.whatwg.org/multipage/scripting.html#dom-context-2d-createpattern step 2:\r\n\r\n> Check the usability of the image argument. If this returns aborted, then an exception has been thrown and the method doesn't return anything; abort these steps. If it returns bad, then return null and abort these steps. "},"comment":{"url":"https://api.github.com/repos/whatwg/html/issues/comments/181560372","html_url":"https://github.com/whatwg/html/issues/655#issuecomment-181560372","issue_url":"https://api.github.com/repos/whatwg/html/issues/655","id":181560372,"user":{"login":"domenic","id":617481,"avatar_url":"https://avatars.githubusercontent.com/u/617481?v=3","gravatar_id":"","url":"https://api.github.com/users/domenic","html_url":"https://github.com/domenic","followers_url":"https://api.github.com/users/domenic/followers","following_url":"https://api.github.com/users/domenic/following{/other_user}","gists_url":"https://api.github.com/users/domenic/gists{/gist_id}","starred_url":"https://api.github.com/users/domenic/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/domenic/subscriptions","organizations_url":"https://api.github.com/users/domenic/orgs","repos_url":"https://api.github.com/users/domenic/repos","events_url":"https://api.github.com/users/domenic/events{/privacy}","received_events_url":"https://api.github.com/users/domenic/received_events","type":"User","site_admin":false},"created_at":"2016-02-08T20:46:04Z","updated_at":"2016-02-08T20:46:04Z","body":"I suppose we should check that browsers actually do return null? But assuming that's the case, this should be simply a matter of adding `?` to the return type (`CanvasPattern?`)."}}