LibWeb: Support legacy xlink:href attribute for linked gradients

...and rename the related functions to something more descriptive.

Userland/Libraries/LibWeb/SVG/SVGGradientElement.cpp

@@ -35,8 +35,8 @@ GradientUnits SVGGradientElement::gradient_units() const
 {
     if (m_gradient_units.has_value())
         return *m_gradient_units;
-    if (auto href = xlink_href())
+    if (auto gradient = linked_gradient())
-        return href->gradient_units();
+        return gradient->gradient_units();
     return GradientUnits::ObjectBoundingBox;
 }
 
@@ -44,8 +44,8 @@ Optional<Gfx::AffineTransform> SVGGradientElement::gradient_transform() const
 {
     if (m_gradient_transform.has_value())
         return m_gradient_transform;
-    if (auto href = xlink_href())
+    if (auto gradient = linked_gradient())
-        return href->gradient_transform();
+        return gradient->gradient_transform();
     return {};
 }
 
@@ -78,11 +78,13 @@ void SVGGradientElement::add_color_stops(Gfx::SVGGradientPaintStyle& paint_style
     });
 }
 
-JS::GCPtr<SVGGradientElement const> SVGGradientElement::xlink_href() const
+JS::GCPtr<SVGGradientElement const> SVGGradientElement::linked_gradient() const
 {
     // FIXME: This entire function is an ad-hoc hack!
     // It can only resolve #<ids> in the same document.
-    if (auto href = get_attribute("href"); !href.is_empty()) {
+
+    auto link = has_attribute("href") ? get_attribute("href") : get_attribute("xlink:href");
+    if (auto href = link; !href.is_empty()) {
         auto url = document().parse_url(href);
         auto id = url.fragment();
         if (id.is_empty())

Userland/Libraries/LibWeb/SVG/SVGGradientElement.h

@@ -39,7 +39,7 @@ protected:
 
     virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
 
-    JS::GCPtr<SVGGradientElement const> xlink_href() const;
+    JS::GCPtr<SVGGradientElement const> linked_gradient() const;
 
     Gfx::AffineTransform gradient_paint_transform(SVGPaintContext const&) const;
 
@@ -52,8 +52,8 @@ protected:
             callback(stop);
         });
         if (!color_stops_found) {
-            if (auto href = xlink_href())
+            if (auto gradient = linked_gradient())
-                href->for_each_color_stop(callback);
+                gradient->for_each_color_stop(callback);
         }
     }
 

Userland/Libraries/LibWeb/SVG/SVGLinearGradientElement.cpp

@@ -51,8 +51,8 @@ NumberPercentage SVGLinearGradientElement::start_x() const
 {
     if (m_x1.has_value())
         return *m_x1;
-    if (auto href = linear_gradient_xlink_href())
+    if (auto gradient = linked_linear_gradient())
-        return href->start_x();
+        return gradient->start_x();
     // If the attribute is not specified, the effect is as if a value of '0%' were specified.
     return NumberPercentage::create_percentage(0);
 }
@@ -62,8 +62,8 @@ NumberPercentage SVGLinearGradientElement::start_y() const
 {
     if (m_y1.has_value())
         return *m_y1;
-    if (auto href = linear_gradient_xlink_href())
+    if (auto gradient = linked_linear_gradient())
-        return href->start_x();
+        return gradient->start_x();
     // If the attribute is not specified, the effect is as if a value of '0%' were specified.
     return NumberPercentage::create_percentage(0);
 }
@@ -73,8 +73,8 @@ NumberPercentage SVGLinearGradientElement::end_x() const
 {
     if (m_x2.has_value())
         return *m_x2;
-    if (auto href = linear_gradient_xlink_href())
+    if (auto gradient = linked_linear_gradient())
-        return href->start_x();
+        return gradient->start_x();
     // If the attribute is not specified, the effect is as if a value of '100%' were specified.
     return NumberPercentage::create_percentage(100);
 }
@@ -84,8 +84,8 @@ NumberPercentage SVGLinearGradientElement::end_y() const
 {
     if (m_y2.has_value())
         return *m_y2;
-    if (auto href = linear_gradient_xlink_href())
+    if (auto gradient = linked_linear_gradient())
-        return href->start_x();
+        return gradient->start_x();
     // If the attribute is not specified, the effect is as if a value of '0%' were specified.
     return NumberPercentage::create_percentage(0);
 }

Userland/Libraries/LibWeb/SVG/SVGLinearGradientElement.h

@@ -33,10 +33,10 @@ protected:
     virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
 
 private:
-    JS::GCPtr<SVGLinearGradientElement const> linear_gradient_xlink_href() const
+    JS::GCPtr<SVGLinearGradientElement const> linked_linear_gradient() const
     {
-        if (auto href = xlink_href(); href && is<SVGLinearGradientElement>(*href))
+        if (auto gradient = linked_gradient(); gradient && is<SVGLinearGradientElement>(*gradient))
-            return &verify_cast<SVGLinearGradientElement>(*href);
+            return &verify_cast<SVGLinearGradientElement>(*gradient);
         return {};
     }
 

Userland/Libraries/LibWeb/SVG/SVGRadialGradientElement.cpp

@@ -57,8 +57,8 @@ NumberPercentage SVGRadialGradientElement::start_circle_x() const
         return *m_fx;
     // If the element references an element that specifies a value for 'fx', then the value of 'fx' is
     // inherited from the referenced element.
-    if (auto href = radial_gradient_xlink_href())
+    if (auto gradient = linked_radial_gradient())
-        return href->start_circle_x();
+        return gradient->start_circle_x();
     // If attribute ‘fx’ is not specified, ‘fx’ will coincide with the presentational value of ‘cx’ for
     // the element whether the value for 'cx' was inherited or not.
     return end_circle_x();
@@ -71,8 +71,8 @@ NumberPercentage SVGRadialGradientElement::start_circle_y() const
         return *m_fy;
     // If the element references an element that specifies a value for 'fy', then the value of 'fy' is
     // inherited from the referenced element.
-    if (auto href = radial_gradient_xlink_href())
+    if (auto gradient = linked_radial_gradient())
-        return href->start_circle_y();
+        return gradient->start_circle_y();
     // If attribute ‘fy’ is not specified, ‘fy’ will coincide with the presentational value of ‘cy’ for
     // the element whether the value for 'cy' was inherited or not.
     return end_circle_y();
@@ -86,8 +86,8 @@ NumberPercentage SVGRadialGradientElement::start_circle_radius() const
         return *m_fr;
     // if the element references an element that specifies a value for 'fr', then the value of
     // 'fr' is inherited from the referenced element.
-    if (auto href = radial_gradient_xlink_href())
+    if (auto gradient = linked_radial_gradient())
-        return href->start_circle_radius();
+        return gradient->start_circle_radius();
     // If the attribute is not specified, the effect is as if a value of '0%' were specified.
     return NumberPercentage::create_percentage(0);
 }
@@ -97,8 +97,8 @@ NumberPercentage SVGRadialGradientElement::end_circle_x() const
 {
     if (m_cx.has_value())
         return *m_cx;
-    if (auto href = radial_gradient_xlink_href())
+    if (auto gradient = linked_radial_gradient())
-        return href->end_circle_x();
+        return gradient->end_circle_x();
     return NumberPercentage::create_percentage(50);
 }
 
@@ -107,8 +107,8 @@ NumberPercentage SVGRadialGradientElement::end_circle_y() const
 {
     if (m_cy.has_value())
         return *m_cy;
-    if (auto href = radial_gradient_xlink_href())
+    if (auto gradient = linked_radial_gradient())
-        return href->end_circle_y();
+        return gradient->end_circle_y();
     return NumberPercentage::create_percentage(50);
 }
 
@@ -118,8 +118,8 @@ NumberPercentage SVGRadialGradientElement::end_circle_radius() const
     // Note: A negative value is an error.
     if (m_r.has_value() && m_r->value() >= 0)
         return *m_r;
-    if (auto href = radial_gradient_xlink_href())
+    if (auto gradient = linked_radial_gradient())
-        return href->end_circle_radius();
+        return gradient->end_circle_radius();
     return NumberPercentage::create_percentage(50);
 }
 

Userland/Libraries/LibWeb/SVG/SVGRadialGradientElement.h

@@ -35,10 +35,10 @@ protected:
     virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
 
 private:
-    JS::GCPtr<SVGRadialGradientElement const> radial_gradient_xlink_href() const
+    JS::GCPtr<SVGRadialGradientElement const> linked_radial_gradient() const
     {
-        if (auto href = xlink_href(); href && is<SVGRadialGradientElement>(*href))
+        if (auto gradient = linked_gradient(); gradient && is<SVGRadialGradientElement>(*gradient))
-            return &verify_cast<SVGRadialGradientElement>(*href);
+            return &verify_cast<SVGRadialGradientElement>(*gradient);
         return {};
     }