Fix RelaxNG factories to raise on parse failure instead of wrapping NULL.

Author: cfis

ext/libxml/ruby_xml_relaxng.c

@@ -63,6 +63,9 @@ static VALUE rxml_relaxng_init_from_uri(VALUE class, VALUE uri)
   xrelaxng = xmlRelaxNGParse(xparser);
   xmlRelaxNGFreeParserCtxt(xparser);
 
+  if (!xrelaxng)
+    rxml_raise(xmlGetLastError());
+
   return TypedData_Wrap_Struct(cXMLRelaxNG, &rxml_relaxng_data_type, xrelaxng);
 }
 
@@ -84,6 +87,9 @@ static VALUE rxml_relaxng_init_from_document(VALUE class, VALUE document)
   xrelaxng = xmlRelaxNGParse(xparser);
   xmlRelaxNGFreeParserCtxt(xparser);
 
+  if (!xrelaxng)
+    rxml_raise(xmlGetLastError());
+
   return TypedData_Wrap_Struct(cXMLRelaxNG, &rxml_relaxng_data_type, xrelaxng);
 }
 
@@ -104,6 +110,9 @@ static VALUE rxml_relaxng_init_from_string(VALUE self, VALUE relaxng_str)
   xrelaxng = xmlRelaxNGParse(xparser);
   xmlRelaxNGFreeParserCtxt(xparser);
 
+  if (!xrelaxng)
+    rxml_raise(xmlGetLastError());
+
   return TypedData_Wrap_Struct(cXMLRelaxNG, &rxml_relaxng_data_type, xrelaxng);
 }
 

test/test_relaxng.rb

@@ -26,6 +26,12 @@ def test_valid
     assert(@doc.validate_relaxng(relaxng))
   end
 
+  def test_parse_failure_raises
+    assert_raises(LibXML::XML::Error) do
+      LibXML::XML::RelaxNG.new("<invalid/>")
+    end
+  end
+
   def test_invalid
     new_node = LibXML::XML::Node.new('invalid', 'this will mess up validation')
     @doc.root << new_node