89240 2012-06-15 12:23:04 -0700 REGRESSION (r112923): getMatchedCSSRules always returning null for parentStyleSheet 2022-07-13 10:12:41 -0700 1 1 1 Unclassified WebKit CSS 528+ (Nightly build) All All RESOLVED WONTFIX https://bugs.webkit.org/show_bug.cgi?id=79653 Regression P1 Normal --- 1 jmayhew webkit-unassigned ap bfulgham joethomas kling koivisto shanestephens tonistiigi oldest_to_newest 650395 0 147873 jmayhew 2012-06-15 12:23:04 -0700 Created attachment 147873 Test html file that shows the bug when pressing the html button. This happens in the webkit nightly and the webkit versions for Chromium 20. The problem does not occur in Safari 5.1.7 for Chrome 19. window.getMatchedCSSRules() should return rule object(s) that have a valid parentStyleSheet property. Recent webkit versions make this api always return a null parentStyleSheet property. Attached is a simple test file. Pressing the button will force a call to window.getMatchedCSSRules() and will display the parentStyleSheet properties value. In Chrome 19 and Safari 5.1.7, the property is non-null. In the webkit nightly it is null. 651758 1 ap 2012-06-18 14:51:24 -0700 Does this affect any live web sites? 651786 2 jmayhew 2012-06-18 15:14:26 -0700 (In reply to comment #1) > Does this affect any live web sites? Per this bug: https://bugs.webkit.org/show_bug.cgi?id=79653 I would say yes. It does affect us, but we aren't live yet. 652985 3 jmayhew 2012-06-19 16:51:04 -0700 After a brief investigation it looks like changeset 112923 has quite a bit of refactoring in this area of CSS in webcore. I think this bug is just an artifact of that effort. In short, StyleResolver::sortAndTransferMatchedRules() calls m_ruleList->rules().append(m_matchedRules[i]->rule()->createCSSOMWrapper()); and is not passing in the parent stylesheet. I think this call to createCSSOMWrapper should pass in the parent but I don't think it is available to the StyleResolver class. Fixing this will require making the parent sheet pointer available to the StyleResolver. This change should probably be done by the people heading the refactoring effort as it will depend on their new class design. Also, StyleRule.h includes the following lines // FIXME: There shouldn't be any need for the null parent version. PassRefPtr<CSSRule> createCSSOMWrapper(CSSStyleSheet* parentSheet = 0) const; PassRefPtr<CSSRule> createCSSOMWrapper(CSSRule* parentRule) const; I agree with the FIXME comment that there should be no default value for the parentSheet parameter. Is there ever a case where a rule should have a null parentSheet/parentRule? If this default value is removed, the resulting errors will indicate the areas that need to be addressed. I hope that helps. 667187 4 jmayhew 2012-07-11 16:11:35 -0700 Okay, our project is no longer under NDA, we are open source and our alpha release is out so I can share it as an example of a web site/chrome extension that relies heavily on getMatchedCSSRules(...) Our extension is available on the chrome web store here https://chrome.google.com/webstore/detail/jjdndclgmfdgpiccmlamlicfjmkognne We had to add a workaround for this bug. When we detect a null parent we have to manually search through the rules to find the matching parent style sheet. This workaround is not 100% reliable so getting this bug fixed is very important to us as is the continued support of the getMatchedCSSRules() api. 1883135 5 bfulgham 2022-07-13 10:09:52 -0700 Chrome and Firefox don't seem to support 'window.getMatchedCSSRules()'. 1883136 6 bfulgham 2022-07-13 10:12:41 -0700 WebKit intends to remove this non-standard function in Bug 79653. We are not likely to take action on this bug. 147873 2012-06-15 12:23:04 -0700 2012-06-15 12:23:04 -0700 Test html file that shows the bug when pressing the html button. parentStyleSheetTest.html text/html 850 jmayhew PCFET0NUWVBFIGh0bWw+CjxodG1sPgo8aGVhZD4KICAgIDx0aXRsZT5UZXN0IGZvciBwYXJlbnQg c3R5bGUgc2hlZXQ8L3RpdGxlPgogICAgCiAgICA8c3R5bGUgdHlwZT0idGV4dC9jc3MiPgogICAg ICAgIGJvZHkgeyB3aWR0aCA6IDEwMCUgfQogICAgPC9zdHlsZT4KICAgIAogICAgPHNjcmlwdCB0 eXBlPSJ0ZXh0L2phdmFzY3JpcHQiPgogICAgICAgIHdpbmRvdy5vbmxvYWQgPSBmdW5jdGlvbigp IHsKICAgICAgICAgICAgdmFyIGJ0biA9IGRvY3VtZW50LmdldEVsZW1lbnRCeUlkKCdidG4nKTsK ICAgICAgICAgICAgYnRuLm9uY2xpY2sgPSBmdW5jdGlvbigpIHsKICAgICAgICAgICAgICAgIHZh ciBtID0gd2luZG93LmdldE1hdGNoZWRDU1NSdWxlcyhkb2N1bWVudC5ib2R5KTsKICAgICAgICAg ICAgICAgIGFsZXJ0KCdSdWxlXCdzIHBhcmVudFN0eWxlU2hlZXQgPSAnICsgbVswXS5wYXJlbnRT dHlsZVNoZWV0KTsKICAgICAgICAgICAgfTsKICAgICAgICB9OwogICAgPC9zY3JpcHQ+CjwvaGVh ZD4KPGJvZHk+CiAgICA8aDE+UHJvYmxlbTogbm8gcGFyZW50U3R5bGVTaGVldCBvbiBDU1MgUnVs ZSBvYmplY3Q8L2gxPgogICA8YnV0dG9uIGlkPSJidG4iPlRlc3Q8L2J1dHRvbj4KICAgCiAgIDxw PlRoaXMgaXMgaGFwcGVucyBvbmx5IHdoZW4gY2FsbGluZyB0aGUgbWV0aG9kIHdpbmRvdy5nZXRN YXRjaGVkQ1NTUnVsZXMoPGVtPmVsZW1lbnQ8L2VtPikuPC9wPgogICA8cD5XaGVuIGdvaW5nIHRo cm91Z2ggdGhlIHN0eWxlIHNoZWV0cyBhcnJheSwgd2Ugc2VlIHRoYXQgZWFjaCBydWxlIGRvZXMg aGF2ZSBhIHBhcmVudFN0eWxlc1NoZWV0IHNldDwvcD4KICAgCjwvYm9keT4KPC9odG1sPg==