Bug 159982 – Stop using valueToStringWithNullCheck() in JSCSSStyleDeclaration::putDelegate()

• Component: CSS
• Status: RESOLVED FIXED

[Chris Dumez]

valueToStringWithNullCheck() treats null as the null String() which is legacy / non standard behavior. The specification says we should treat null as the empty string:
- https://drafts.csswg.org/cssom/#dom-cssstyledeclaration-camel-cased-attribute

Therefore, we should be using valueToStringTreatingNullAsEmptyString() instead.

In practice, there will be no web-exposed behavior change because MutableStyleProperties::setProperty() removes the property wether the value is the null String or the empty String.
The specification says that we should remove the property if the value is the empty string:
- https://drafts.csswg.org/cssom/#dom-cssstyledeclaration-setproperty (step 4)

So our behavior is correct.

[Chris Dumez]

Created attachment 284141 [details]
Patch

[Chris Dumez]

Created attachment 284149 [details]
Patch

[Chris Dumez]

The Mac-wk2 EWS build error is unrelated:
/Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/JSInternalSettingsGenerated.cpp:809:10: error: no member named 'setAllowsInlineMediaPlaybackWithPlaysInlineAttribute' in 'WebCore::InternalSettingsGenerated'; did you mean 'setInlineMediaPlaybackRequiresPlaysInlineAttribute'?
    impl.setAllowsInlineMediaPlaybackWithPlaysInlineAttribute(WTFMove(allowsInlineMediaPlaybackWithPlaysInlineAttribute));
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
         setInlineMediaPlaybackRequiresPlaysInlineAttribute
In file included from /Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/JSInternalSettingsGenerated.cpp:22:
In file included from /Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/JSInternalSettingsGenerated.h:23:
/Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/InternalSettingsGenerated.h:112:10: note: 'setInlineMediaPlaybackRequiresPlaysInlineAttribute' declared here
    void setInlineMediaPlaybackRequiresPlaysInlineAttribute(bool inlineMediaPlaybackRequiresPlaysInlineAttribute);
         ^
/Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/JSInternalSettingsGenerated.cpp:826:10: error: no member named 'setAllowsInlineMediaPlaybackWithWebKitPlaysInlineAttribute' in 'WebCore::InternalSettingsGenerated'; did you mean 'setInlineMediaPlaybackRequiresPlaysInlineAttribute'?
    impl.setAllowsInlineMediaPlaybackWithWebKitPlaysInlineAttribute(WTFMove(allowsInlineMediaPlaybackWithWebKitPlaysInlineAttribute));
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
         setInlineMediaPlaybackRequiresPlaysInlineAttribute
In file included from /Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/JSInternalSettingsGenerated.cpp:22:
In file included from /Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/JSInternalSettingsGenerated.h:23:
/Volumes/Data/EWS/WebKit/WebKitBuild/Release/DerivedSources/WebCore/InternalSettingsGenerated.h:112:10: note: 'setInlineMediaPlaybackRequiresPlaysInlineAttribute' declared here
    void setInlineMediaPlaybackRequiresPlaysInlineAttribute(bool inlineMediaPlaybackRequiresPlaysInlineAttribute);
         ^
2 errors generated.

CompileC /Volumes/Data/EWS/WebKit/WebKitBuild/WebCore.build/Release/WebCoreTestSupport.build/Objects-normal/x86_64/WebCoreTestSupport.o testing/js/WebCoreTestSupport.cpp normal x86_64 c++ com.apple.compilers.llvm.clang.1_0.compiler

[Chris Dumez]

Comment on attachment 284149 [details]
Patch

Clearing flags on attachment: 284149

Committed r203475: <http://trac.webkit.org/changeset/203475>

[Chris Dumez]

All reviewed patches have been landed.  Closing bug.