#16564: test to confirm behavior that regressed in python3.

Also add running of test_email_renamed to the email regrtest.  It contains
tests that the base email/tests/test_email.py does not, which I discovered
while trying to backport this test for confirmation of the behavior.

Lib/email/test/test_email_renamed.py

@@ -994,6 +994,21 @@ class TestMIMEApplication(unittest.TestCase):
         eq(msg.get_payload(), '+vv8/f7/')
         eq(msg.get_payload(decode=True), bytes)
 
+    def test_body_with_encode_noop(self):
+        # Issue 16564: This does not produce an RFC valid message, since to be
+        # valid it should have a CTE of binary.  But the below works, and is
+        # documented as working this way.
+        bytesdata = b'\xfa\xfb\xfc\xfd\xfe\xff'
+        msg = MIMEApplication(bytesdata, _encoder=encoders.encode_noop)
+        self.assertEqual(msg.get_payload(), bytesdata)
+        self.assertEqual(msg.get_payload(decode=True), bytesdata)
+        s = StringIO()
+        g = Generator(s)
+        g.flatten(msg)
+        wireform = s.getvalue()
+        msg2 = email.message_from_string(wireform)
+        self.assertEqual(msg.get_payload(), bytesdata)
+        self.assertEqual(msg2.get_payload(decode=True), bytesdata)
 
 
 # Test the basic MIMEText class

Lib/test/test_email.py

@@ -3,10 +3,12 @@
 
 # The specific tests now live in Lib/email/test
 from email.test.test_email import suite
+from email.test.test_email_renamed import suite as suite2
 from test import test_support
 
 def test_main():
     test_support.run_unittest(suite())
+    test_support.run_unittest(suite2())
 
 if __name__ == '__main__':
     test_main()

Misc/NEWS

@@ -748,6 +748,10 @@ Extension Modules
 Tests
 -----
 
+- We now run both test_email.py and test_email_renamed.py when running the
+  test_email regression test.  test_email_renamed contains some tests that
+  test_email does not.
+
 - Issue #17041: Fix testing when Python is configured with the
   --without-doc-strings option.