Bug 286290 – Add support for the lang attribute in SVG

• Component: SVG
• Status: RESOLVED FIXED

[Deleted User]

https://searchfox.org/wubkat/source/LayoutTests/imported/w3c/web-platform-tests/svg/text/reftests/lang-attribute.svg

According to https://searchfox.org/wubkat/rev/d4766b667963256e41db8c72a02613067074d834/LayoutTests/TestExpectations#2345 it fails.

The error lies presumably in a missing check in https://searchfox.org/wubkat/rev/d4766b667963256e41db8c72a02613067074d834/Source/WebCore/dom/Element.cpp#4547.

[Radar WebKit Bug Importer]

<rdar://problem/143751056>

[Karl Dubost]

Created attachment 478905 [details]
rendering in safari, firefox, chrome

The test is failing just because of the font chosen to render the text I guess. 
Maybe Vitor knows why?

[Karl Dubost]

Code snippet for the console to extract the relevant information for each browser:

  document.querySelectorAll('text, tspan').forEach(el => {
    console.log(
      el.tagName +
      '  lang=' + el.getAttribute('lang') +
      '  matches:lang(ja)=' + el.matches(':lang(ja)') +
      '  matches:lang(zh-CN)=' + el.matches(':lang(zh-CN)') +
      '  matches:lang(zh-TW)=' + el.matches(':lang(zh-TW)') +
      '  "' + el.textContent.trim().substring(0, 20) + '"'
    );
  });

Safari: 
[Log] text  lang=null  matches:lang(ja)=false  matches:lang(zh-CN)=false  matches:lang(zh-TW)=false  "今骨直                                                                   
    今骨直                                                                                                                                                                               
    今骨直"                                                                                                                                                                              
[Log] tspan  lang=ja  matches:lang(ja)=true  matches:lang(zh-CN)=false  matches:lang(zh-TW)=false  "今骨直"                                                                              
[Log] tspan  lang=zh-CN  matches:lang(ja)=false  matches:lang(zh-CN)=true  matches:lang(zh-TW)=false  "今骨直"                                                                           
[Log] tspan  lang=zh-TW  matches:lang(ja)=false  matches:lang(zh-CN)=false  matches:lang(zh-TW)=true  "今骨直" 


Firefox: 
text  lang=null  matches:lang(ja)=false                          
matches:lang(zh-CN)=false  matches:lang(zh-TW)=false  "今骨直                                                                                                                            
    今骨直                                                                                                                                                                               
    今骨直" debugger eval code:2:13                                                                                                                                                      
tspan  lang=ja  matches:lang(ja)=true  matches:lang(zh-CN)=false  matches:lang(zh-TW)=false  "今骨直" debugger eval code:2:13                                                            
tspan  lang=zh-CN  matches:lang(ja)=false  matches:lang(zh-CN)=true  matches:lang(zh-TW)=false  "今骨直" debugger eval code:2:13                                                         
tspan  lang=zh-TW  matches:lang(ja)=false  matches:lang(zh-CN)=false  matches:lang(zh-TW)=true  "今骨直" 


Chrome: 
text  lang=null  matches:lang(ja)=false  matches:lang(zh-CN)=false      
matches:lang(zh-TW)=false  "今骨直                                                                                                                                                       
    今骨直                                                                                                                                                                               
    今骨直"                                                                                                                                                                              
VM17:2 tspan  lang=ja  matches:lang(ja)=true  matches:lang(zh-CN)=false  matches:lang(zh-TW)=false  "今骨直"                                                                             
VM17:2 tspan  lang=zh-CN  matches:lang(ja)=false  matches:lang(zh-CN)=true  matches:lang(zh-TW)=false  "今骨直"                                                                          
VM17:2 tspan  lang=zh-TW  matches:lang(ja)=false  matches:lang(zh-CN)=false  matches:lang(zh-TW)=true  "今骨直"

[Karl Dubost]

HTMLElement::collectPresentationalHintsForAttribute() (HTMLElement.cpp:259-265) maps lang and xml:lang to -webkit-locale via mapLanguageAttributeToLocale(), which calls addPropertyToPresentationalHintStyle(style, CSSPropertyWebkitLocale, ...).

SVGElement::collectPresentationalHintsForAttribute() (SVGElement.cpp:1026-1031) only handles SVG-specific presentation attributes (fill, stroke, etc.) via cssPropertyIdForSVGAttributeName(). It does not handle lang/xml:lang at all. The language never becomes a -webkit-locale presentational hint.

[Karl Dubost]

Add lang/xml:lang → -webkit-locale mapping in SVGElement, mirroring what HTMLElement does.

SVGElement.cpp — hasPresentationalHintsForAttribute():
============
bool SVGElement::hasPresentationalHintsForAttribute(const QualifiedName& name) const
{
    if (cssPropertyIdForSVGAttributeName(name, document().settings()) > 0)
        return true;
    if (name.matches(XMLNames::langAttr) || name.matches(HTMLNames::langAttr))
        return true;
    return StyledElement::hasPresentationalHintsForAttribute(name);
}
============



SVGElement.cpp — collectPresentationalHintsForAttribute():
============
void SVGElement::collectPresentationalHintsForAttribute(const QualifiedName& name, const AtomString& value, MutableStyleProperties& style)
{
    CSSPropertyID propertyID = cssPropertyIdForSVGAttributeName(name, document().settings());
    if (propertyID > 0)
        addPropertyToPresentationalHintStyle(style, propertyID, value);
    else if (name.matches(XMLNames::langAttr))
        mapLanguageAttributeToLocale(value, style);
    else if (name.matches(HTMLNames::langAttr) && !hasAttributeWithoutSynchronization(XMLNames::langAttr))
        mapLanguageAttributeToLocale(value, style);
}
============

Note: mapLanguageAttributeToLocale() is currently a private method on HTMLElement.

[Karl Dubost]

Pull request: https://github.com/WebKit/WebKit/pull/61919

[EWS]

Committed 310495@main (f7fa439ccd03): <https://commits.webkit.org/310495@main>

Reviewed commits have been landed. Closing PR #61919 and removing active labels.