From d33b90880b8eb024daa73bc3fd39aca0bc791ff1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lucas=20Treffenst=C3=A4dt?= <lucas@treffenstaedt.de>
Date: Mon, 13 Jan 2020 13:54:08 +0100
Subject: [PATCH 1/2] CramMD5ClientAuthenticator now specifies the digestmod
 argument to hmac.HMAC constructor explicitly.

---
 src/twisted/mail/_cred.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/twisted/mail/_cred.py b/src/twisted/mail/_cred.py
index 9d3646948..43c406f90 100644
--- a/src/twisted/mail/_cred.py
+++ b/src/twisted/mail/_cred.py
@@ -8,6 +8,7 @@ Credential managers for L{twisted.mail}.
 from __future__ import absolute_import, division
 
 import hmac
+import hashlib
 
 from zope.interface import implementer
 
@@ -28,7 +29,7 @@ class CramMD5ClientAuthenticator:
 
 
     def challengeResponse(self, secret, chal):
-        response = hmac.HMAC(secret, chal).hexdigest().encode('ascii')
+        response = hmac.HMAC(secret, chal, digestmod = hashlib.md5).hexdigest().encode('ascii')
         return self.user + b' ' + response
 
 
-- 
2.26.2

From 694bc67f3cf7d36a6f512f0b76882e85d0966dd2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Poisson?= <goffi@goffi.org>
Date: Sun, 17 Nov 2019 19:48:53 +0100
Subject: [PATCH 2/2] Fix parsing of namespaced attributes with Python 3.8 in
 twisted.words.xish.domish.ExpatElementStream

---
 src/twisted/words/newsfragments/9730.bugfix |  1 +
 src/twisted/words/test/test_domish.py       | 17 +++++++++++++++++
 src/twisted/words/xish/domish.py            | 11 +++++++++--
 3 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 src/twisted/words/newsfragments/9730.bugfix

diff --git a/src/twisted/words/newsfragments/9730.bugfix b/src/twisted/words/newsfragments/9730.bugfix
new file mode 100644
index 000000000..5c91305c8
--- /dev/null
+++ b/src/twisted/words/newsfragments/9730.bugfix
@@ -0,0 +1 @@
+Fixed parsing of streams with Python 3.8 when there are spaces in namespaces or namespaced attributes in twisted.words.xish.domish.ExpatElementStream
diff --git a/src/twisted/words/test/test_domish.py b/src/twisted/words/test/test_domish.py
index a8f8fa76b..cd16e3a4d 100644
--- a/src/twisted/words/test/test_domish.py
+++ b/src/twisted/words/test/test_domish.py
@@ -350,6 +350,23 @@ class DomishStreamTestsMixin:
             self.elements[0].attributes, {(" bar baz ", "baz"): "quux"})
 
 
+    def test_attributesWithNamespaces(self):
+        """
+        Attributes with namespace are parsed without Exception.
+        (https://twistedmatrix.com/trac/ticket/9730 regression test)
+        """
+
+        xml = b"""<root xmlns:test='http://example.org' xml:lang='en'>
+                    <test:test>test</test:test>
+                  </root>"""
+
+        # with Python 3.8 and without #9730 fix, the following error would
+        # happen at next line:
+        # ``RuntimeError: dictionary keys changed during iteration``
+        self.stream.parse(xml)
+        self.assertEqual(self.elements[0].uri, "http://example.org")
+
+
     def testChildPrefix(self):
         xml = b"<root xmlns='testns' xmlns:foo='testns2'><foo:child/></root>"
 
diff --git a/src/twisted/words/xish/domish.py b/src/twisted/words/xish/domish.py
index 2063c410a..fc49285f5 100644
--- a/src/twisted/words/xish/domish.py
+++ b/src/twisted/words/xish/domish.py
@@ -807,11 +807,18 @@ class ExpatElementStream:
             qname = ('', name)
 
         # Process attributes
+        newAttrs = {}
+        toDelete = []
         for k, v in attrs.items():
             if " " in k:
                 aqname = k.rsplit(" ", 1)
-                attrs[(aqname[0], aqname[1])] = v
-                del attrs[k]
+                newAttrs[(aqname[0], aqname[1])] = v
+                toDelete.append(k)
+
+        attrs.update(newAttrs)
+
+        for k in toDelete:
+            del attrs[k]
 
         # Construct the new element
         e = Element(qname, self.defaultNsStack[-1], attrs, self.localPrefixes)
-- 
2.26.2