Let CSS attributes have higher priority than the plain XML attributes

Although seemingly not well specified, the common behavior of web
browsers and other SVG renderers is to give priority to attribute
values specified in the CSS style attribute, in case of conflict. So
make qtsvg do the same, by moving the CSS parsing block to after the
XML attribute parsing block.

Fixes: QTBUG-100068
Pick-to: 6.4
Change-Id: I769303d69509511103d96e8d26e2cfeac1f19494
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 107 insertions, 108 deletions

diff --git a/src/svg/qsvghandler.cpp b/src/svg/qsvghandler.cpp
index e730eed..677dc97 100644
--- a/src/svg/qsvghandler.cpp
+++ b/src/svg/qsvghandler.cpp
@@ -195,112 +195,6 @@ struct QSvgAttributes
 
 QSvgAttributes::QSvgAttributes(const QXmlStreamAttributes &xmlAttributes, QSvgHandler *handler)
 {
-#ifndef QT_NO_CSSPARSER
-    QStringView style = xmlAttributes.value(QLatin1String("style"));
-    if (!style.isEmpty()) {
-        handler->parseCSStoXMLAttrs(style.toString(), &m_cssAttributes);
-        for (int j = 0; j < m_cssAttributes.count(); ++j) {
-            const QSvgCssAttribute &attribute = m_cssAttributes.at(j);
-            QStringView name = attribute.name;
-            QStringView value = attribute.value;
-            if (name.isEmpty())
-                continue;
-
-            switch (name.at(0).unicode()) {
-
-            case 'c':
-                if (name == QLatin1String("color"))
-                    color = value;
-                else if (name == QLatin1String("color-opacity"))
-                    colorOpacity = value;
-                else if (name == QLatin1String("comp-op"))
-                    compOp = value;
-                break;
-
-            case 'd':
-                if (name == QLatin1String("display"))
-                    display = value;
-                break;
-
-            case 'f':
-                if (name == QLatin1String("fill"))
-                    fill = value;
-                else if (name == QLatin1String("fill-rule"))
-                    fillRule = value;
-                else if (name == QLatin1String("fill-opacity"))
-                    fillOpacity = value;
-                else if (name == QLatin1String("font-family"))
-                    fontFamily = value;
-                else if (name == QLatin1String("font-size"))
-                    fontSize = value;
-                else if (name == QLatin1String("font-style"))
-                    fontStyle = value;
-                else if (name == QLatin1String("font-weight"))
-                    fontWeight = value;
-                else if (name == QLatin1String("font-variant"))
-                    fontVariant = value;
-                break;
-            case 'i':
-                if (name == QLatin1String("image-rendering"))
-                    imageRendering = value;
-                break;
-
-            case 'o':
-                if (name == QLatin1String("opacity"))
-                    opacity = value;
-                else if (name == QLatin1String("offset"))
-                    offset = value;
-                break;
-
-            case 's':
-                if (name.length() > 5 && name.mid(1, 5) == QLatin1String("troke")) {
-                    QStringView strokeRef = name.mid(6, name.length() - 6);
-                    if (strokeRef.isEmpty())
-                        stroke = value;
-                    else if (strokeRef == QLatin1String("-dasharray"))
-                        strokeDashArray = value;
-                    else if (strokeRef == QLatin1String("-dashoffset"))
-                        strokeDashOffset = value;
-                    else if (strokeRef == QLatin1String("-linecap"))
-                        strokeLineCap = value;
-                    else if (strokeRef == QLatin1String("-linejoin"))
-                        strokeLineJoin = value;
-                    else if (strokeRef == QLatin1String("-miterlimit"))
-                        strokeMiterLimit = value;
-                    else if (strokeRef == QLatin1String("-opacity"))
-                        strokeOpacity = value;
-                    else if (strokeRef == QLatin1String("-width"))
-                        strokeWidth = value;
-                }
-                else if (name == QLatin1String("stop-color"))
-                    stopColor = value;
-                else if (name == QLatin1String("stop-opacity"))
-                    stopOpacity = value;
-                break;
-
-            case 't':
-                if (name == QLatin1String("text-anchor"))
-                    textAnchor = value;
-                else if (name == QLatin1String("transform"))
-                    transform = value;
-                break;
-
-            case 'v':
-                if (name == QLatin1String("vector-effect"))
-                    vectorEffect = value;
-                else if (name == QLatin1String("visibility"))
-                    visibility = value;
-                break;
-
-            default:
-                break;
-           }
-        }
-    }
-#else
-    Q_UNUSED(handler);
-#endif // QT_NO_CSSPARSER
-
     for (int i = 0; i < xmlAttributes.count(); ++i) {
         const QXmlStreamAttribute &attribute = xmlAttributes.at(i);
         QStringView name = attribute.qualifiedName();
@@ -376,8 +270,7 @@ QSvgAttributes::QSvgAttributes(const QXmlStreamAttributes &xmlAttributes, QSvgHa
                     strokeOpacity = value;
                 else if (strokeRef == QLatin1String("-width"))
                     strokeWidth = value;
-            }
-            else if (name == QLatin1String("stop-color"))
+            } else if (name == QLatin1String("stop-color"))
                 stopColor = value;
             else if (name == QLatin1String("stop-opacity"))
                 stopOpacity = value;
@@ -407,6 +300,112 @@ QSvgAttributes::QSvgAttributes(const QXmlStreamAttributes &xmlAttributes, QSvgHa
         }
     }
 
+    // If a style attribute is present, let its attribute settings override the plain attribute
+    // values. The spec seems to indicate that, and it is common behavior in svg renderers.
+#ifndef QT_NO_CSSPARSER
+    QStringView style = xmlAttributes.value(QLatin1String("style"));
+    if (!style.isEmpty()) {
+        handler->parseCSStoXMLAttrs(style.toString(), &m_cssAttributes);
+        for (int j = 0; j < m_cssAttributes.count(); ++j) {
+            const QSvgCssAttribute &attribute = m_cssAttributes.at(j);
+            QStringView name = attribute.name;
+            QStringView value = attribute.value;
+            if (name.isEmpty())
+                continue;
+
+            switch (name.at(0).unicode()) {
+
+            case 'c':
+                if (name == QLatin1String("color"))
+                    color = value;
+                else if (name == QLatin1String("color-opacity"))
+                    colorOpacity = value;
+                else if (name == QLatin1String("comp-op"))
+                    compOp = value;
+                break;
+
+            case 'd':
+                if (name == QLatin1String("display"))
+                    display = value;
+                break;
+
+            case 'f':
+                if (name == QLatin1String("fill"))
+                    fill = value;
+                else if (name == QLatin1String("fill-rule"))
+                    fillRule = value;
+                else if (name == QLatin1String("fill-opacity"))
+                    fillOpacity = value;
+                else if (name == QLatin1String("font-family"))
+                    fontFamily = value;
+                else if (name == QLatin1String("font-size"))
+                    fontSize = value;
+                else if (name == QLatin1String("font-style"))
+                    fontStyle = value;
+                else if (name == QLatin1String("font-weight"))
+                    fontWeight = value;
+                else if (name == QLatin1String("font-variant"))
+                    fontVariant = value;
+                break;
+            case 'i':
+                if (name == QLatin1String("image-rendering"))
+                    imageRendering = value;
+                break;
+
+            case 'o':
+                if (name == QLatin1String("opacity"))
+                    opacity = value;
+                else if (name == QLatin1String("offset"))
+                    offset = value;
+                break;
+
+            case 's':
+                if (name.length() > 5 && name.mid(1, 5) == QLatin1String("troke")) {
+                    QStringView strokeRef = name.mid(6, name.length() - 6);
+                    if (strokeRef.isEmpty())
+                        stroke = value;
+                    else if (strokeRef == QLatin1String("-dasharray"))
+                        strokeDashArray = value;
+                    else if (strokeRef == QLatin1String("-dashoffset"))
+                        strokeDashOffset = value;
+                    else if (strokeRef == QLatin1String("-linecap"))
+                        strokeLineCap = value;
+                    else if (strokeRef == QLatin1String("-linejoin"))
+                        strokeLineJoin = value;
+                    else if (strokeRef == QLatin1String("-miterlimit"))
+                        strokeMiterLimit = value;
+                    else if (strokeRef == QLatin1String("-opacity"))
+                        strokeOpacity = value;
+                    else if (strokeRef == QLatin1String("-width"))
+                        strokeWidth = value;
+                } else if (name == QLatin1String("stop-color"))
+                    stopColor = value;
+                else if (name == QLatin1String("stop-opacity"))
+                    stopOpacity = value;
+                break;
+
+            case 't':
+                if (name == QLatin1String("text-anchor"))
+                    textAnchor = value;
+                else if (name == QLatin1String("transform"))
+                    transform = value;
+                break;
+
+            case 'v':
+                if (name == QLatin1String("vector-effect"))
+                    vectorEffect = value;
+                else if (name == QLatin1String("visibility"))
+                    visibility = value;
+                break;
+
+            default:
+                break;
+            }
+        }
+    }
+#else
+    Q_UNUSED(handler);
+#endif // QT_NO_CSSPARSER
 }
 
 #ifndef QT_NO_CSSPARSER