add backend agnostic UUID datatype

Added new backend-agnostic :class:`_types.Uuid` datatype generalized from
the PostgreSQL dialects to now be a core type, as well as migrated
:class:`_types.UUID` from the PostgreSQL dialect. Thanks to Trevor Gross
for the help on this.

also includes:

* corrects some missing behaviors in the suite literal fixtures
  test where row round trips weren't being correctly asserted.
* fixes some of the ISO literal date rendering added in
  952383f9ee0 for #5052 to truncate datetime strings for date/time
  datatypes in the same way that drivers typically do for bound
  parameters; this was not working fully and wasn't caught by the
  broken test fixture

Fixes: #7212
Change-Id: I981ac6d34d278c18281c144430a528764c241b04

1 files changed, 0 insertions, 34 deletions

diff --git a/lib/sqlalchemy/dialects/postgresql/asyncpg.py b/lib/sqlalchemy/dialects/postgresql/asyncpg.py
index d320c323c..1ec787e1f 100644
--- a/lib/sqlalchemy/dialects/postgresql/asyncpg.py
+++ b/lib/sqlalchemy/dialects/postgresql/asyncpg.py
@@ -138,7 +138,6 @@ from .base import PGDialect
 from .base import PGExecutionContext
 from .base import PGIdentifierPreparer
 from .base import REGCLASS
-from .base import UUID
 from ... import exc
 from ... import pool
 from ... import util
@@ -150,12 +149,6 @@ from ...util.concurrency import await_fallback
 from ...util.concurrency import await_only
 
 
-try:
-    from uuid import UUID as _python_UUID  # noqa
-except ImportError:
-    _python_UUID = None
-
-
 class AsyncpgString(sqltypes.String):
     render_bind_cast = True
 
@@ -237,30 +230,6 @@ class AsyncpgJSONPathType(json.JSONPathType):
         return process
 
 
-class AsyncpgUUID(UUID):
-    render_bind_cast = True
-
-    def bind_processor(self, dialect):
-        if not self.as_uuid and dialect.use_native_uuid:
-
-            def process(value):
-                if value is not None:
-                    value = _python_UUID(value)
-                return value
-
-            return process
-
-    def result_processor(self, dialect, coltype):
-        if not self.as_uuid and dialect.use_native_uuid:
-
-            def process(value):
-                if value is not None:
-                    value = str(value)
-                return value
-
-            return process
-
-
 class AsyncpgNumeric(sqltypes.Numeric):
     render_bind_cast = True
 
@@ -831,8 +800,6 @@ class PGDialect_asyncpg(PGDialect):
     statement_compiler = PGCompiler_asyncpg
     preparer = PGIdentifierPreparer_asyncpg
 
-    use_native_uuid = True
-
     colspecs = util.update_copy(
         PGDialect.colspecs,
         {
@@ -842,7 +809,6 @@ class PGDialect_asyncpg(PGDialect):
             sqltypes.DateTime: AsyncpgDateTime,
             sqltypes.Interval: AsyncPgInterval,
             INTERVAL: AsyncPgInterval,
-            UUID: AsyncpgUUID,
             sqltypes.Boolean: AsyncpgBoolean,
             sqltypes.Integer: AsyncpgInteger,
             sqltypes.BigInteger: AsyncpgBigInteger,