Support "lang" and "xml:lang" attributes.

Partial fix for https://gitlab.com/inkscape/inbox/issues/951

6 files changed, 41 insertions, 2 deletions

diff --git a/src/attributes.cpp b/src/attributes.cpp
index 7353c35ed..49ec997ec 100644
--- a/src/attributes.cpp
+++ b/src/attributes.cpp
@@ -409,6 +409,7 @@ static SPStyleProp const props[] = {
 
     /* XML */
     {SP_ATTR_XML_SPACE, "xml:space"},
+    {SP_ATTR_XML_LANG,  "xml:lang"},
 
     /* typeset */
     {SP_ATTR_TEXT_NOMARKUP, "inkscape:srcNoMarkup"},
diff --git a/src/attributes.h b/src/attributes.h
index 7a49e2808..d1d4c5aa7 100644
--- a/src/attributes.h
+++ b/src/attributes.h
@@ -415,6 +415,7 @@ enum SPAttributeEnum : unsigned {
 
     /* XML */
     SP_ATTR_XML_SPACE,
+    SP_ATTR_XML_LANG,
 
     /* typeset */
     SP_ATTR_TEXT_NOMARKUP,
diff --git a/src/libnrtype/Layout-TNG-Compute.cpp b/src/libnrtype/Layout-TNG-Compute.cpp
index 03ccc62d7..aad2744b5 100644
--- a/src/libnrtype/Layout-TNG-Compute.cpp
+++ b/src/libnrtype/Layout-TNG-Compute.cpp
@@ -1148,6 +1148,14 @@ void  Layout::Calculator::_buildPangoItemizationForPara(ParagraphInfo *para) con
             pango_attr_list_insert(attributes_list, attribute_font_features);
 #endif
 
+            // Set language
+            SPObject * object = static_cast<SPObject *>(text_source->source_cookie);
+            if (!object->lang.empty()) {
+                PangoLanguage* language = pango_language_from_string(object->lang.c_str());
+                PangoAttribute *attribute_language = pango_attr_language_new( language );
+                pango_attr_list_insert(attributes_list, attribute_language);
+            }
+
             // ownership of attribute is assumed by the list
             font->Unref();
         }
diff --git a/src/libnrtype/Layout-TNG.h b/src/libnrtype/Layout-TNG.h
index 4f096abab..596e112b3 100644
--- a/src/libnrtype/Layout-TNG.h
+++ b/src/libnrtype/Layout-TNG.h
@@ -718,7 +718,8 @@ private:
         std::vector<SVGLength> rotate;
         SVGLength textLength;
         LengthAdjust lengthAdjust;
-        
+        Glib::ustring lang;
+
         // a few functions for some of the more complicated style accesses
         /// The return value must be freed with pango_font_description_free()
         PangoFontDescription *styleGetFontDescription() const;
diff --git a/src/object/sp-object.cpp b/src/object/sp-object.cpp
index 1d7ae6396..dabf5219a 100644
--- a/src/object/sp-object.cpp
+++ b/src/object/sp-object.cpp
@@ -657,8 +657,16 @@ void SPObject::build(SPDocument *document, Inkscape::XML::Node *repr) {
     debug("id=%p, typename=%s", object, g_type_name_from_instance((GTypeInstance*)object));
 
     object->readAttr("xml:space");
+    object->readAttr("lang");
+    object->readAttr("xml:lang");   // "xml:lang" overrides "lang" per spec, read it last.
     object->readAttr("inkscape:label");
     object->readAttr("inkscape:collect");
+
+    // Inherit if not set
+    if (lang.empty() && object->parent) {
+        lang = object->parent->lang;
+    }
+
     if(object->cloned && (repr->attribute("id")) ) // The cases where this happens are when the "original" has no id. This happens
                                                    // if it is a SPString (a TextNode, e.g. in a <title>), or when importing
                                                    // stuff externally modified to have no id. 
@@ -888,6 +896,7 @@ void SPObject::set(SPAttributeEnum key, gchar const* value) {
     SPObject* object = this;
 
     switch (key) {
+
         case SP_ATTR_ID:
 
             //XML Tree being used here.
@@ -928,6 +937,7 @@ void SPObject::set(SPAttributeEnum key, gchar const* value) {
                 object->_default_label = nullptr;
             }
             break;
+
         case SP_ATTR_INKSCAPE_LABEL:
             g_free(object->_label);
             if (value) {
@@ -938,6 +948,7 @@ void SPObject::set(SPAttributeEnum key, gchar const* value) {
             g_free(object->_default_label);
             object->_default_label = nullptr;
             break;
+
         case SP_ATTR_INKSCAPE_COLLECT:
             if ( value && !std::strcmp(value, "always") ) {
                 object->setCollectionPolicy(SPObject::ALWAYS_COLLECT);
@@ -945,6 +956,7 @@ void SPObject::set(SPAttributeEnum key, gchar const* value) {
                 object->setCollectionPolicy(SPObject::COLLECT_WITH_PARENT);
             }
             break;
+
         case SP_ATTR_XML_SPACE:
             if (value && !std::strcmp(value, "preserve")) {
                 object->xml_space.value = SP_XML_SPACE_PRESERVE;
@@ -959,10 +971,26 @@ void SPObject::set(SPAttributeEnum key, gchar const* value) {
             }
             object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_STYLE_MODIFIED_FLAG);
             break;
+
+        case SP_ATTR_LANG:
+            if (value) {
+                lang = value;
+                // To do: sanity check
+            }
+            break;
+
+        case SP_ATTR_XML_LANG:
+            if (value) {
+                lang = value;
+                // To do: sanity check
+            }
+            break;
+
         case SP_ATTR_STYLE:
             object->style->readFromObject( object );
             object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_STYLE_MODIFIED_FLAG);
             break;
+
         default:
             break;
     }
@@ -1373,7 +1401,6 @@ void SPObject::setAttribute(Glib::ustring const &key, Glib::ustring const &value
                   value.empty() ? nullptr : value.c_str(), ex);
 }
 
-
 void SPObject::removeAttribute(gchar const *key, SPException *ex)
 {
     /* If exception is not clear, return */
diff --git a/src/object/sp-object.h b/src/object/sp-object.h
index baa2bf9c7..190f24253 100644
--- a/src/object/sp-object.h
+++ b/src/object/sp-object.h
@@ -210,6 +210,7 @@ public:
     unsigned int uflags : 8;
     unsigned int mflags : 8;
     SPIXmlSpace xml_space;
+    Glib::ustring lang;
     unsigned int hrefcount; /* number of xlink:href references */
     unsigned int _total_hrefcount; /* our hrefcount + total descendants */
     SPDocument *document; /* Document we are part of */