Replace c extension with cython versions.workflow_test_cython

Re-implement c version immutabledict / processors / resultproxy / utils with cython.
Performance is in general in par or better than the c version
Added a collection module that has cython version of OrderedSet and IdentitySet

Added a new test/perf file to compare the implementations.
Run ``python test/perf/compiled_extensions.py all`` to execute the comparison test.

See results here: https://docs.google.com/document/d/1nOcDGojHRtXEkuy4vNXcW_XOJd9gqKhSeALGG3kYr6A/edit?usp=sharing

Fixes: #7256
Change-Id: I2930ef1894b5048210384728118e586e813f6a76
Signed-off-by: Federico Caselli <cfederico87@gmail.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/test/orm/test_merge.py b/test/orm/test_merge.py
index 8866223cc..0f29cfc56 100644
--- a/test/orm/test_merge.py
+++ b/test/orm/test_merge.py
@@ -31,10 +31,20 @@ from sqlalchemy.testing import not_in
 from sqlalchemy.testing.fixtures import fixture_session
 from sqlalchemy.testing.schema import Column
 from sqlalchemy.testing.schema import Table
+from sqlalchemy.util import has_compiled_ext
 from sqlalchemy.util import OrderedSet
 from test.orm import _fixtures
 
 
+if has_compiled_ext():
+    # cython ordered set is immutable, subclass it with a python
+    # class so that its method can be replaced
+    _OrderedSet = OrderedSet
+
+    class OrderedSet(_OrderedSet):
+        pass
+
+
 class MergeTest(_fixtures.FixtureTest):
     """Session.merge() functionality"""