# HG changeset patch
# Parent 32d3770c19586a67b5f60ec69e5bb5fd2d59b84d
Issue #13378: use non global namespaces for the serializer.

diff --git a/Lib/test/test_xml_etree.py b/Lib/test/test_xml_etree.py
--- a/Lib/test/test_xml_etree.py
+++ b/Lib/test/test_xml_etree.py
@@ -1717,6 +1717,8 @@
     >>> s = ET.SubElement(e, "{not-default}elem")
     >>> serialize(e, default_namespace="default") # 2
     '<elem xmlns="default" xmlns:ns1="not-default"><elem /><ns1:elem /></elem>'
+    >>> serialize(e, namespaces={"default": ""})
+    '<elem xmlns="default" xmlns:ns1="not-default"><elem /><ns1:elem /></elem>'
 
     >>> e = ET.Element("{default}elem")
     >>> s = ET.SubElement(e, "{default}elem")
@@ -1724,6 +1726,9 @@
     >>> serialize(e, default_namespace="default") # 3
     Traceback (most recent call last):
     ValueError: cannot use non-qualified names with default_namespace option
+    >>> serialize(e, namespaces={"default": ""})
+    Traceback (most recent call last):
+    ValueError: cannot use non-qualified names with default_namespace option
 
     """
 
@@ -1851,6 +1856,20 @@
     >>> ET.register_namespace('test10777', 'http://myuri/')
     """
 
+def check_issue13378():
+    """
+    Pass specific, non-global namespaces to the serializer.
+
+    >>> elem = ET.XML('<house:iq xmlns:house="http://localhost/house"/>')
+    >>> serialize(elem, namespaces={'http://localhost/house': 'house'})
+    '<house:iq xmlns:house="http://localhost/house" />'
+    >>> serialize(elem)
+    '<ns0:iq xmlns:ns0="http://localhost/house" />'
+    >>> serialize(elem, namespaces={'http://localhost/house': 'home'})
+    '<home:iq xmlns:home="http://localhost/house" />'
+
+    """
+
 # --------------------------------------------------------------------
 
 
diff --git a/Lib/xml/etree/ElementTree.py b/Lib/xml/etree/ElementTree.py
--- a/Lib/xml/etree/ElementTree.py
+++ b/Lib/xml/etree/ElementTree.py
@@ -813,7 +813,8 @@
               encoding=None,
               xml_declaration=None,
               default_namespace=None,
-              method=None):
+              method=None,
+              namespaces=None):
         # assert self._root is not None
         if not method:
             method = "xml"
@@ -857,7 +858,11 @@
         if method == "text":
             _serialize_text(write, self._root)
         else:
-            qnames, namespaces = _namespaces(self._root, default_namespace)
+            # if custom namespaces...
+            namespaces = dict(namespaces or {})
+            if default_namespace:
+                namespaces[default_namespace] = ""
+            qnames = _qnames(self._root, namespaces)
             serialize = _serialize[method]
             serialize(write, self._root, qnames, namespaces)
         if file_or_filename is not file:
@@ -870,17 +875,23 @@
 # --------------------------------------------------------------------
 # serialization support
 
-def _namespaces(elem, default_namespace=None):
+def _qnames(elem, namespaces):
     # identify namespaces used in this tree
 
     # maps qnames to *encoded* prefix:local names
     qnames = {None: None}
 
+    # any uri is mapped to ""?
+    has_default_namespace = ("" in namespaces.values())
+
+    if namespaces:
+        namespace_map = _namespace_map.copy()
+        namespace_map.update(namespaces)
+        namespaces.clear()
+    else:
+        namespace_map = _namespace_map
+
     # maps uri:s to prefixes
-    namespaces = {}
-    if default_namespace:
-        namespaces[default_namespace] = ""
-
     def add_qname(qname):
         # calculate serialized qname representation
         try:
@@ -888,7 +899,7 @@
                 uri, tag = qname[1:].rsplit("}", 1)
                 prefix = namespaces.get(uri)
                 if prefix is None:
-                    prefix = _namespace_map.get(uri)
+                    prefix = namespace_map.get(uri)
                     if prefix is None:
                         prefix = "ns%d" % len(namespaces)
                     if prefix != "xml":
@@ -898,7 +909,7 @@
                 else:
                     qnames[qname] = tag # default element
             else:
-                if default_namespace:
+                if has_default_namespace:
                     # FIXME: can this be handled in XML 1.0?
                     raise ValueError(
                         "cannot use non-qualified names with "
@@ -909,11 +920,7 @@
             _raise_serialization_error(qname)
 
     # populate qname and namespaces table
-    try:
-        iterate = elem.iter
-    except AttributeError:
-        iterate = elem.getiterator # cET compatibility
-    for elem in iterate():
+    for elem in elem.iter():
         tag = elem.tag
         if isinstance(tag, QName):
             if tag.text not in qnames:
@@ -933,7 +940,7 @@
         text = elem.text
         if isinstance(text, QName) and text.text not in qnames:
             add_qname(text.text)
-    return qnames, namespaces
+    return qnames
 
 def _serialize_xml(write, elem, qnames, namespaces):
     tag = elem.tag
@@ -1152,13 +1159,13 @@
 # @return An (optionally) encoded string containing the XML data.
 # @defreturn string
 
-def tostring(element, encoding=None, method=None):
+def tostring(element, encoding=None, method=None, **kw):
     class dummy:
         pass
     data = []
     file = dummy()
     file.write = data.append
-    ElementTree(element).write(file, encoding, method=method)
+    ElementTree(element).write(file, encoding, method=method, **kw)
     if encoding in (str, "unicode"):
         return "".join(data)
     else:
@@ -1179,13 +1186,13 @@
 # @defreturn sequence
 # @since 1.3
 
-def tostringlist(element, encoding=None, method=None):
+def tostringlist(element, encoding=None, method=None, **kw):
     class dummy:
         pass
     data = []
     file = dummy()
     file.write = data.append
-    ElementTree(element).write(file, encoding, method=method)
+    ElementTree(element).write(file, encoding, method=method, **kw)
     # FIXME: merge small fragments into larger parts
     return data