10686 – event instanceof MouseEvent throws exception

RESOLVED FIXED 10686

event instanceof MouseEvent throws exception

https://bugs.webkit.org/show_bug.cgi?id=10686

Summary event instanceof MouseEvent throws exception

Eric Seidel (no email)

Reported 2006-09-01 22:44:50 PDT

myDiv instanceof Element returns false! Firefox (correctly) returns true. http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference:Operators:Special_Operators:instanceof_Operator

Attachments
A few different instanceof tests (1.33 KB, application/xhtml+xml) 2006-12-09 07:40 PST, C Snover	no flags	Details
Correct testcase. (1.37 KB, application/xhtml+xml) 2006-12-09 07:45 PST, C Snover	no flags	Details
patch (15.30 KB, patch) 2007-12-30 14:12 PST, Sam Weinig	oliver: review+	Details Formatted Diff Diff
Show Obsolete (2) View All Add attachment proposed patch, testcase, etc.

C Snover

Comment 1 2006-12-09 07:40:34 PST

Created attachment 11787 [details] A few different instanceof tests instanceof is a bit more broken than just Element. I've attached a very simple testcase for instanceof. All six tests should return TRUE, but only the Object test returns TRUE; the others either return FALSE or error.

C Snover

Comment 2 2006-12-09 07:41:45 PST

Comment on attachment 11787 [details] A few different instanceof tests <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>instanceof test</title> <meta http-equiv="Content-Type" content="application/xhtml+xml; charset=UTF-8"/> </head> <script type="text/javascript"> // <![CDATA[ window.addEventListener('load', function() { document.getElementById('clickme').addEventListener('click', function(evt) { try { alert("Object: " + (evt instanceof Object)); } catch(e) { errstr(e); } try { alert("Event: " + (evt instanceof Event)); } catch(e) { errstr(e); } try { alert("MouseEvent: " + (evt instanceof MouseEvent)); } catch(e) { errstr(e); } try { alert("Element: " + (evt.target instanceof Element)); } catch(e) { errstr(e); } try { alert("HTMLElement: " + (evt.target instanceof HTMLElement)); } catch(e) { errstr(e); } try { alert("HTMLDivElement: " + (evt.target instanceof HTMLDivElement)); } catch(e) { errstr(e); } }, false); }, false); function errstr(e) { var errstr = ""; for(var i in e) { errstr += i + " = " + e[i] + "\n"; } alert(errstr); }; // ]]> </script> <body> <div id="clickme">Click here to test instanceof Object, Event, MouseEvent, Element, HTMLElement, and HTMLDivElement (one alert per test)</div> </body> </html>

C Snover

Comment 3 2006-12-09 07:45:13 PST

Created attachment 11788 [details] Correct testcase. Whoops. That button did not do what I thought it was going to do. Sorry about the spam.

Geoffrey Garen

Comment 4 2006-12-11 23:49:14 PST

This is because the global constructors don't have .prototype properties.

David Kilzer (:ddkilzer)

Comment 5 2007-03-06 18:52:16 PST