Modernize internal reflection

- Deprecated remaining engine-level introspection and utility methods
including :meth:`.Engine.run_callable`, :meth:`.Engine.transaction`,
:meth:`.Engine.table_names`, :meth:`.Engine.has_table`.   The utility
methods are superseded by modern context-manager patterns, and the table
introspection tasks are suited by the :class:`.Inspector` object.

- The internal dialect method ``Dialect.reflecttable`` has been removed.  A
review of third party dialects has not found any making use of this method,
as it was already documented as one that should not be used by external
dialects.  Additionally, the private ``Engine._run_visitor`` method
is also removed.

- The long-deprecated ``Inspector.get_table_names.order_by`` parameter has
been removed.

- The :paramref:`.Table.autoload_with` parameter now accepts an :class:`.Inspector` object
directly, as well as any :class:`.Engine` or :class:`.Connection` as was the case before.

Fixes: #4755
Change-Id: Iec3a8b0f3e298ba87d532b16fac1e1132f464e21

1 files changed, 43 insertions, 0 deletions

diff --git a/test/ext/test_horizontal_shard.py b/test/ext/test_horizontal_shard.py
index affd7112c..0f3bc8f37 100644
--- a/test/ext/test_horizontal_shard.py
+++ b/test/ext/test_horizontal_shard.py
@@ -437,6 +437,49 @@ class DistinctEngineShardTest(ShardTest, fixtures.TestBase):
 
 
 class AttachedFileShardTest(ShardTest, fixtures.TestBase):
+    """Use modern schema conventions along with SQLite ATTACH."""
+
+    schema = "changeme"
+
+    def _init_dbs(self):
+        e = testing_engine("sqlite://")
+        with e.connect() as conn:
+            for i in range(1, 5):
+                conn.execute(
+                    'ATTACH DATABASE "shard%s_%s.db" AS shard%s'
+                    % (i, provision.FOLLOWER_IDENT, i)
+                )
+
+        db1 = e.execution_options(schema_translate_map={"changeme": "shard1"})
+        db2 = e.execution_options(schema_translate_map={"changeme": "shard2"})
+        db3 = e.execution_options(schema_translate_map={"changeme": "shard3"})
+        db4 = e.execution_options(schema_translate_map={"changeme": "shard4"})
+
+        self.engine = e
+        return db1, db2, db3, db4
+
+    def teardown(self):
+        clear_mappers()
+
+        self.engine.connect().invalidate()
+        for i in range(1, 5):
+            os.remove("shard%d_%s.db" % (i, provision.FOLLOWER_IDENT))
+
+
+class TableNameConventionShardTest(ShardTest, fixtures.TestBase):
+    """This fixture uses a single SQLite database along with a table naming
+    convention to achieve sharding.   Event hooks are used to rewrite SQL
+    statements.
+
+    This used to be called "AttachedFileShardTest" but I didn't see any
+    ATTACH going on.
+
+    The approach taken by this test is awkward and I wouldn't recommend  using
+    this pattern in a real situation.  I'm not sure of the history of this test
+    but it likely predates when we knew how to use real ATTACH in SQLite.
+
+    """
+
     schema = "changeme"
 
     def _init_dbs(self):