another patch from Brent Hendricks to add new handlers with the various

* python/generator.py python/libxml.py: another patch from Brent
  Hendricks to add new handlers with the various validity contexts
* python/tests/Makefile.am python/tests/validDTD.py
  python/tests/validRNG.py python/tests/validSchemas.py: also
  added the regression tests he provided
Daniel

python/tests/validRNG.py

@@ -0,0 +1,76 @@
+#!/usr/bin/python -u
+import libxml2
+import sys
+
+ARG = 'test string'
+
+class ErrorHandler:
+
+    def __init__(self):
+        self.errors = []
+
+    def handler(self, msg, data):
+        if data != ARG:
+            raise Exception, "Error handler did not receive correct argument"
+        self.errors.append(msg)
+
+# Memory debug specific
+libxml2.debugMemory(1)
+
+schema="""<?xml version="1.0"?>
+<element name="foo"
+         xmlns="http://relaxng.org/ns/structure/1.0"
+         xmlns:a="http://relaxng.org/ns/annotation/1.0"
+         xmlns:ex1="http://www.example.com/n1"
+         xmlns:ex2="http://www.example.com/n2">
+  <a:documentation>A foo element.</a:documentation>
+  <element name="ex1:bar1">
+    <empty/>
+  </element>
+  <element name="ex2:bar2">
+    <empty/>
+  </element>
+</element>
+"""
+
+valid="""<?xml version="1.0"?>
+<foo><pre1:bar1 xmlns:pre1="http://www.example.com/n1"/><pre2:bar2 xmlns:pre2="http://www.example.com/n2"/></foo>"""
+
+invalid="""<?xml version="1.0"?>
+<foo><pre1:bar1 xmlns:pre1="http://www.example.com/n1">bad</pre1:bar1><pre2:bar2 xmlns:pre2="http://www.example.com/n2"/></foo>"""
+
+rngp = libxml2.relaxNGNewMemParserCtxt(schema, len(schema))
+rngs = rngp.relaxNGParse()
+ctxt = rngs.relaxNGNewValidCtxt()
+e = ErrorHandler()
+ctxt.setValidityErrorHandler(e.handler, e.handler, ARG)
+
+# Test valid document
+doc = libxml2.parseDoc(valid)
+ret = doc.relaxNGValidateDoc(ctxt)
+if ret != 0 or e.errors:
+    print "error doing RelaxNG validation"
+    sys.exit(1)
+doc.freeDoc()
+
+# Test invalid document
+doc = libxml2.parseDoc(invalid)
+ret = doc.relaxNGValidateDoc(ctxt)
+if ret == 0 or not e.errors:
+    print "Error: document supposed to be RelaxNG invalid"
+    sys.exit(1)
+doc.freeDoc()
+
+del rngp
+del rngs
+del ctxt
+libxml2.relaxNGCleanupTypes()
+
+# Memory debug specific
+libxml2.cleanupParser()
+if libxml2.debugMemory(1) == 0:
+    print "OK"
+else:
+    print "Memory leak %d bytes" % (libxml2.debugMemory(1))
+    libxml2.dumpMemory()
+