removals: all unicode encoding / decoding

Removed here includes:

* convert_unicode parameters
* encoding create_engine() parameter
* description encoding support
* "non-unicode fallback" modes under Python 2
* String symbols regarding Python 2 non-unicode fallbacks
* any concept of DBAPIs that don't accept unicode
  statements, unicode bound parameters, or that return bytes
  for strings anywhere except an explicit Binary / BLOB
  type
* unicode processors in Python / C

Risk factors:

* Whether all DBAPIs do in fact return Unicode objects for
  all entries in cursor.description now
* There was logic for mysql-connector trying to determine
  description encoding.   A quick test shows Unicode coming
  back but it's not clear if there are still edge cases where
  they return bytes.  if so, these are bugs in that driver,
  and at most we would only work around it in the mysql-connector
  DBAPI itself (but we won't do that either).
* It seems like Oracle 8 was not expecting unicode bound parameters.
  I'm assuming this was all Python 2 stuff and does not apply
  for modern cx_Oracle under Python 3.
* third party dialects relying upon built in unicode encoding/decoding
  but it's hard to imagine any non-SQLAlchemy database driver not
  dealing exclusively in Python unicode strings in Python 3

Change-Id: I97d762ef6d4dd836487b714d57d8136d0310f28a
References: #7257

1 files changed, 0 insertions, 26 deletions

diff --git a/test/sql/test_defaults.py b/test/sql/test_defaults.py
index 31cc15155..92e59d9a8 100644
--- a/test/sql/test_defaults.py
+++ b/test/sql/test_defaults.py
@@ -13,7 +13,6 @@ from sqlalchemy import MetaData
 from sqlalchemy import Sequence
 from sqlalchemy import String
 from sqlalchemy import testing
-from sqlalchemy import Unicode
 from sqlalchemy.schema import CreateTable
 from sqlalchemy.sql import literal_column
 from sqlalchemy.sql import select
@@ -29,8 +28,6 @@ from sqlalchemy.testing.schema import Column
 from sqlalchemy.testing.schema import Table
 from sqlalchemy.types import TypeDecorator
 from sqlalchemy.types import TypeEngine
-from sqlalchemy.util import b
-from sqlalchemy.util import u
 
 
 class DDLTest(fixtures.TestBase, AssertsCompiledSQL):
@@ -1428,29 +1425,6 @@ class ServerDefaultsOnPKTest(fixtures.TestBase):
         eq_(list(connection.execute(t.select())), [(5, "data")])
 
 
-class UnicodeDefaultsTest(fixtures.TestBase):
-    __backend__ = True
-
-    def test_no_default(self):
-        Column(Unicode(32))
-
-    def test_unicode_default(self):
-        default = u("foo")
-        Column(Unicode(32), default=default)
-
-    def test_nonunicode_default(self):
-        default = b("foo")
-        assert_raises_message(
-            sa.exc.SAWarning,
-            "Unicode column 'foobar' has non-unicode "
-            "default value b?'foo' specified.",
-            Column,
-            "foobar",
-            Unicode(32),
-            default=default,
-        )
-
-
 class InsertFromSelectTest(fixtures.TablesTest):
     __backend__ = True