Create initial 2.0 engine implementation

Implemented the SQLAlchemy 2 :func:`.future.create_engine` function which
is used for forwards compatibility with SQLAlchemy 2.   This engine
features always-transactional behavior with autobegin.

Allow execution options per statement execution.  This includes
that the before_execute() and after_execute() events now accept
an additional dictionary with these options, empty if not
passed; a legacy event decorator is added for backwards compatibility
which now also emits a deprecation warning.

Add some basic tests for execution, transactions, and
the new result object.   Build out on a new testing fixture
that swaps in the future engine completely to start with.

Change-Id: I70e7338bb3f0ce22d2f702537d94bb249bd9fb0a
Fixes: #4644

1 files changed, 10 insertions, 0 deletions

diff --git a/test/sql/test_sequences.py b/test/sql/test_sequences.py
index 8beee514a..1d78c0904 100644
--- a/test/sql/test_sequences.py
+++ b/test/sql/test_sequences.py
@@ -279,6 +279,11 @@ class SequenceExecTest(fixtures.TestBase):
             self._assert_seq_result(r.inserted_primary_key[0])
 
 
+class FutureSequenceExecTest(fixtures.FutureEngineMixin, SequenceExecTest):
+    __requires__ = ("sequences",)
+    __backend__ = True
+
+
 class SequenceTest(fixtures.TestBase, testing.AssertsCompiledSQL):
     __requires__ = ("sequences",)
     __backend__ = True
@@ -396,6 +401,11 @@ class SequenceTest(fixtures.TestBase, testing.AssertsCompiledSQL):
         eq_(result.inserted_primary_key, [1])
 
 
+class FutureSequenceTest(fixtures.FutureEngineMixin, SequenceTest):
+    __requires__ = ("sequences",)
+    __backend__ = True
+
+
 class TableBoundSequenceTest(fixtures.TablesTest):
     __requires__ = ("sequences",)
     __backend__ = True