# This is a combination of 3 commits.

# This is the 1st commit message:

Updated SSL.py to fix problem caused by SSL_WANT_READ or SSL_WANT_WRITE errors. 

When SSL_WANT_READ or SSL_WANT_WRITE are encountered, it's typical to retry the call but this must be repeated with the exact same arguments. Without this change, openSSL requires that the address of the buffer passed is the same. However, buffers in python can change location in some circumstances which cause the retry to fail.  By add the setting SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER, the requirement for the same buffer address is forgiven and the retry has a better chance of success.  See cherrypy/cheroot#245 for discussion.
# This is the commit message pyca#2:

fixed format for flake8/black

# This is the commit message pyca#3:

E721 errors raised by flake8

src/OpenSSL/SSL.py

@@ -865,7 +865,10 @@ def __init__(self, method):
         self._cookie_generate_helper = None
         self._cookie_verify_helper = None
 
-        self.set_mode(_lib.SSL_MODE_ENABLE_PARTIAL_WRITE)
+        self.set_mode(
+            _lib.SSL_MODE_ENABLE_PARTIAL_WRITE
+            | _lib.SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER
+        )
         if version is not None:
             self.set_min_proto_version(version)
             self.set_max_proto_version(version)

tests/test_crypto.py

@@ -1740,7 +1740,7 @@ def test_construction(self):
         certificate = X509()
         assert isinstance(certificate, X509)
         assert type(certificate).__name__ == "X509"
-        assert type(certificate) == X509
+        assert type(certificate) is X509
 
     def test_set_version_wrong_args(self):
         """
@@ -3148,7 +3148,7 @@ def test_construction(self):
         """
         revoked = Revoked()
         assert isinstance(revoked, Revoked)
-        assert type(revoked) == Revoked
+        assert type(revoked) is Revoked
         assert revoked.get_serial() == b"00"
         assert revoked.get_rev_date() is None
         assert revoked.get_reason() is None
@@ -3443,8 +3443,8 @@ def test_get_revoked(self):
 
         revs = crl.get_revoked()
         assert len(revs) == 2
-        assert type(revs[0]) == Revoked
-        assert type(revs[1]) == Revoked
+        assert type(revs[0]) is Revoked
+        assert type(revs[1]) is Revoked
         assert revs[0].get_serial() == b"03AB"
         assert revs[1].get_serial() == b"0100"
         assert revs[0].get_rev_date() == now

tests/test_ssl.py

@@ -190,7 +190,7 @@ def join_bytes_or_unicode(prefix, suffix):
     The return type is the same as the type of ``prefix``.
     """
     # If the types are the same, nothing special is necessary.
-    if type(prefix) == type(suffix):
+    if type(prefix) is type(suffix):
         return join(prefix, suffix)
 
     # Otherwise, coerce suffix to the type of prefix.