Class DOMImplementation

Lib/xml/dom/minidom.py:1428–1505

class DOMImplementation(DOMImplementationLS):
    _features = [("core", "1.0"),
                 ("core", "2.0"),
                 ("core", None),
                 ("xml", "1.0"),
                 ("xml", "2.0"),
                 ("xml", None),
                 ("ls-load", "3.0"),
                 ("ls-load", None),
                 ]

    def hasFeature(self, feature, version):
        if version == "":
            version = None
        return (feature.lower(), version) in self._features

    def createDocument(self, namespaceURI, qualifiedName, doctype):
        if doctype and doctype.parentNode is not None:
            raise xml.dom.WrongDocumentErr(
                "doctype object owned by another DOM tree")
        doc = self._create_document()

        add_root_element = not (namespaceURI is None
                                and qualifiedName is None
                                and doctype is None)

        if not qualifiedName and add_root_element:
            # The spec is unclear what to raise here; SyntaxErr
            # would be the other obvious candidate. Since Xerces raises
            # InvalidCharacterErr, and since SyntaxErr is not listed
            # for createDocument, that seems to be the better choice.
            # XXX: need to check for illegal characters here and in
            # createElement.

            # DOM Level III clears this up when talking about the return value
            # of this function.  If namespaceURI, qName and DocType are
            # Null the document is returned without a document element
            # Otherwise if doctype or namespaceURI are not None
            # Then we go back to the above problem
            raise xml.dom.InvalidCharacterErr("Element with no name")

        if add_root_element:
            prefix, localname = _nssplit(qualifiedName)
            if prefix == "xml" \
               and namespaceURI != "http://www.w3.org/XML/1998/namespace":
                raise xml.dom.NamespaceErr("illegal use of 'xml' prefix")
            if prefix and not namespaceURI:
                raise xml.dom.NamespaceErr(
                    "illegal use of prefix without namespaces")
            element = doc.createElementNS(namespaceURI, qualifiedName)
            if doctype:
                doc.appendChild(doctype)
            doc.appendChild(element)

        if doctype:
            doctype.parentNode = doctype.ownerDocument = doc

        doc.doctype = doctype