Bug 170765 – Assertion failed under WebCore::ApplyStyleCommand::applyBlockStyle.

• Component: HTML Editing
• Status: RESOLVED FIXED

[Per Arne Vollan]

I have not been able to reproduce this myself, but in some cases an assertion fails under WebCore::ApplyStyleCommand::applyBlockStyle:

0   com.apple.JavaScriptCore      	0x000000010bfdaf64 WTFCrash + 36
1   com.apple.WebCore             	0x0000000111e9408f WebCore::ApplyStyleCommand::applyBlockStyle(WebCore::EditingStyle*) + 1535
2   com.apple.WebCore             	0x0000000111e93a5d WebCore::ApplyStyleCommand::doApply() + 349
3   com.apple.WebCore             	0x000000011210468a WebCore::CompositeEditCommand::apply() + 314
4   com.apple.WebCore             	0x0000000112104521 WebCore::applyCommand(WTF::PassRefPtr<WebCore::CompositeEditCommand>) + 17
5   com.apple.WebCore             	0x0000000112642639 WebCore::Editor::applyParagraphStyle(WebCore::StyleProperties*, WebCore::EditAction) + 521
6   com.apple.WebCore             	0x0000000112660349 WebCore::executeApplyParagraphStyle(WebCore::Frame&, WebCore::EditorCommandSource, WebCore::EditAction, WebCore::CSSPropertyID, WTF::String const&) + 233
7   com.apple.WebCore             	0x000000011265b5e2 WebCore::executeJustifyCenter(WebCore::Frame&, WebCore::Event*, WebCore::EditorCommandSource, WTF::String const&) + 98
8   com.apple.WebCore             	0x000000011265af33 WebCore::Editor::Command::execute(WTF::String const&, WebCore::Event*) const + 211
9   com.apple.WebCore             	0x00000001124f2d69 WebCore::Document::execCommand(WTF::String const&, bool, WTF::String const&) + 89
10  com.apple.WebCore             	0x000000011307a124 WebCore::jsDocumentPrototypeFunctionExecCommandCaller(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&) + 660
11  com.apple.WebCore             	0x00000001130646f2 long long WebCore::BindingCaller<WebCore::JSDocument>::callOperation<&(WebCore::jsDocumentPrototypeFunctionExecCommandCaller(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState*, char const*) + 658
12  com.apple.WebCore             	0x0000000113064448 WebCore::jsDocumentPrototypeFunctionExecCommand(JSC::ExecState*) + 40
13  ???                           	0x0000200287201028 0 + 35195229048872
14  com.apple.JavaScriptCore      	0x000000010b91f41f llint_entry + 29979

[Per Arne Vollan]

rdar://problem/31441955

[Per Arne Vollan]

Created attachment 306896 [details]
Patch

[Wenson Hsieh]

Comment on attachment 306896 [details]
Patch

Occasionally, we use ASSERTS to detect early on when we get into an inconsistent or unexpected state, even though in release, we are able to handle the inconsistency gracefully (in this case, with an is<> check). So even though some error cases are handled gracefully by release builds, there may still be value in keeping an ASSERT for debug builds.

However, I'm not certain this is the case here.

[Per Arne Vollan]

rdar://problem/30297145

[Maciej Stachowiak]

Comment on attachment 306896 [details]
Patch

Not sure if this is a good change or not, but in any case the patch no longer applies as-is.

[Ahmad Saleem]

Blink updated it here - https://src.chromium.org/viewvc/blink?view=revision&revision=177283

https://github.com/WebKit/WebKit/blob/85f4c97a6e063901a359c620aa1007c7c3ebd7ea/Source/WebCore/editing/ApplyStyleCommand.cpp#L269

[EWS]

Committed 257617@main (eb072c37fe4e): <https://commits.webkit.org/257617@main>

Reviewed commits have been landed. Closing PR #7342 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/103178512>