20379 2012-12-13 18:40:10 +0000 Should Window's "document" property return the Window's document? 2013-06-04 20:55:42 +0000 1 1 1 Unclassified WHATWG HTML unspecified Other other RESOLVED FIXED http://www.whatwg.org/specs/web-apps/current-work/#the-window-object P3 normal Unsorted 1 contributor ian bzbarsky ian mike zcorpan contributor oldest_to_newest 80116 0 contributor 2012-12-13 18:40:10 +0000 Specification: http://www.whatwg.org/specs/web-apps/current-work/multipage/browsers.html Multipage: http://www.whatwg.org/C#the-window-object Complete: http://www.whatwg.org/c#the-window-object Comment: Should Window's "document" property return the Window Posted from: 173.48.81.109 by bzbarsky@mit.edu User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:20.0) Gecko/20121213 Firefox/20.0 80117 1 bzbarsky 2012-12-13 18:41:27 +0000 Silly comment form submitting itself early... What I meant to say was: Should Window's "document" property really return the document of the currently active Window in the browsing context, or should it return the Window's document (if any)? Seems to me like the latter would be preferable... Note, though, that this would mean that window.document and bareword "document" have slightly different behavior. 80164 2 zcorpan 2012-12-14 08:55:17 +0000 Having document and window.document be different seems confusing... 80165 3 bzbarsky 2012-12-14 08:57:17 +0000 Yes, but having: <script> var doc = document; function f() { alert(doc == document); } </script> start alerting false at some point is just as confusing... Running script in navigated-from windows is just confusing; fact of life. 80762 4 ian 2012-12-31 05:07:26 +0000 Why would it mean than window.document and document would have different behaviour? Bareword |document| is short for |this.document|; |window.document| is short for |this.window.document|. |this.window === this| always. |this| is a WindowProxy. Since WindowProxy always return the Window of the active Document, and you can't get a reference to a raw Window ever, as far as I can tell it doesn't matter whether Window.document returns the Window's document (that is, always the active Document's Window's Document), or whether it returns the active Document. They're the same thing. 80785 5 bzbarsky 2012-12-31 06:53:39 +0000 > Bareword |document| is short for |this.document| As a matter of fact, it's not in implementations. Did you try it? The former does a lookup on the ES global (the Window) while the latter does a lookup on the WindowProxy. And they can't possibly be the same, note, because barewords are lookups on the scope chain, not on objects. You can see this most clearly in with blocks and inside inline event handlers, where converting bareword "foo" lookup to "this.foo" would give totally different behavior. I suggest you try testcases like the one in comment 3, where the frame containing that script is unloaded and then the function f is called, in some UAs to see how it behaves. 83977 6 ian 2013-03-05 00:40:00 +0000 bz: Do you have a test case showing this? I haven't been able to construct a test case that contradicts comment 4 when the scope chain is otherwise uninteresting. (Note that the spec requires "If the script's global object is a Window object, then in JavaScript, the ThisBinding of the global execution context for this script must be the Window object's WindowProxy object, rather than the global object.") 83984 7 bzbarsky 2013-03-05 02:31:27 +0000 There's a testcase in http://lists.w3.org/Archives/Public/public-script-coord/2012OctDec/0328.html But let me attach it here too, just so you can play with it. 83985 8 1328 bzbarsky 2013-03-05 02:31:48 +0000 Created attachment 1328 Subframe for testcase 83986 9 1329 bzbarsky 2013-03-05 02:33:11 +0000 Created attachment 1329 Testcase You may have to save them both locally or put them on another server to test sanely because this Bugzilla is slightly HTML-attachment hostile. 83987 10 bzbarsky 2013-03-05 02:33:57 +0000 Note also that the ThisBinding and the scope chain are totally separate concepts, for what that's worth. 86485 11 ian 2013-04-22 17:36:05 +0000 Wow, I somehow was going through life assuming the ThisBinding was what was on the scope chain. Crazy. Sorry about that. Ok, looks like all the browsers agree that it should return the Window's document. 86486 12 contributor 2013-04-22 17:40:41 +0000 Checked in as WHATWG revision r7845. Check-in comment: Match reality better. (Turns out parts of the spec already assumed this was defined this way anyway.) http://html5.org/tools/web-apps-tracker?from=7844&to=7845 88663 13 contributor 2013-06-04 20:55:42 +0000 Checked in as WHATWG revision r7899. Check-in comment: Fix some typos or copypasta. http://html5.org/tools/web-apps-tracker?from=7898&to=7899 1328 2013-03-05 02:31:48 +0000 2013-03-05 02:31:48 +0000 Subframe for testcase foo.html text/html 232 bzbarsky PCFET0NUWVBFIGh0bWw+CiAgPHNjcmlwdD4KICAgIHZhciBkb2MgPSBkb2N1bWVudDsKICAgIGZ1 bmN0aW9uIGYoKSB7CiAgICAgIGFsZXJ0KChkb2MgPT0gZG9jdW1lbnQpICsgIlxuIiArCiAgICAg ICAgICAgIChkb2MgPT0gdGhpcy5kb2N1bWVudCkgKyAiXG4iICsKICAgICAgICAgICAgZG9jLlVS TCArICJcbiIgKwogICAgICAgICAgICB0aGlzLmRvY3VtZW50LlVSTCk7CiAgICB9CiAgPC9zY3Jp cHQ+Cg== 1329 2013-03-05 02:33:11 +0000 2013-03-05 02:33:11 +0000 Testcase test.html text/html 303 bzbarsky PCFET0NUWVBFIGh0bWw+CjxpZnJhbWUgc3JjPSJodHRwczovL3d3dy53My5vcmcvQnVncy9QdWJs aWMvYXR0YWNobWVudC5jZ2k/aWQ9MTMyOCI+PC9pZnJhbWU+CjxzY3JpcHQ+CiAgdmFyIGZ1bmM7 CiAgd2luZG93Lm9ubG9hZCA9IGZ1bmN0aW9uKCkgewogICAgZnVuYyA9IHdpbmRvd1swXS5mOwog ICAgZG9jdW1lbnQucXVlcnlTZWxlY3RvcigiaWZyYW1lIikub25sb2FkID0gZnVuY3Rpb24oKSB7 CiAgICAgIGZ1bmMoKTsKICAgIH0KICAgIHdpbmRvd1swXS5sb2NhdGlvbiA9ICJhYm91dDpibGFu ayI7CiAgfQo8L3NjcmlwdD4K