remapNamespacePrefix: Preserve prefix of attribute names

Preserve prefix of attribute names when copying them over to the new
node.  This fixes an unintentional rewrite of `xml:space` to `space`
that also caused scour to strip whitespace that should have been
preserved.

Closes: #239
Signed-off-by: Niels Thykier <niels@thykier.net>

scour/scour.py

@@ -3401,7 +3401,7 @@ def remapNamespacePrefix(node, oldprefix, newprefix):
         attrList = node.attributes
         for i in range(attrList.length):
             attr = attrList.item(i)
-            newNode.setAttributeNS(attr.namespaceURI, attr.localName, attr.nodeValue)
+            newNode.setAttributeNS(attr.namespaceURI, attr.name, attr.nodeValue)
 
         # clone and add all the child nodes
         for child in node.childNodes:

test_scour.py

@@ -1502,7 +1502,16 @@ class RemoveRedundantSvgNamespacePrefix(unittest.TestCase):
         doc = scourXmlFile('unittests/redundant-svg-namespace.svg').documentElement
         r = doc.getElementsByTagNameNS(SVGNS, 'rect')[1]
         self.assertEqual(r.tagName, 'rect',
-                         'Redundant svg: prefix not removed')
+                         'Redundant svg: prefix not removed from rect')
+        t = doc.getElementsByTagNameNS(SVGNS, 'text')[0]
+        self.assertEqual(t.tagName, 'text',
+                         'Redundant svg: prefix not removed from text')
+
+        # Regression test for #239
+        self.assertEqual(t.getAttribute('xml:space'), 'preserve',
+                         'Required xml: prefix removed in error')
+        self.assertEqual(t.getAttribute("space"), '',
+                         'Required xml: prefix removed in error')
 
 
 class RemoveDefaultGradX1Value(unittest.TestCase):

unittests/redundant-svg-namespace.svg

@@ -5,4 +5,5 @@
 		<title>Test</title>
 	</svg:rect>
 	<vector:rect height="100" width="100"/>
+	<svg:text xml:space="preserve">  Hallo World  </svg:text>
 </svg>