Create a framework to allow all SQLALCHEMY_WARN_20 to pass

As the test suite has widespread use of many patterns
that are deprecated, enable SQLALCHEMY_WARN_20 globally
for the test suite but then break the warnings filter
out into a whole list of all the individual warnings
we are looking for.  this way individual changesets
can target a specific class of warning, as many of these
warnings will indivdidually affect dozens of files
and potentially hundreds of lines of code.

Many warnings are also resolved here as this
patch started out that way.   From this point
forward there should be changesets that target a
subset of the warnings at a time.

For expediency, updates some migration 2.0 docs
for ORM as well.

Change-Id: I98b8defdf7c37b818b3824d02f7668e3f5f31c94

1 files changed, 17 insertions, 8 deletions

diff --git a/lib/sqlalchemy/testing/profiling.py b/lib/sqlalchemy/testing/profiling.py
index f52827ca5..48e44428b 100644
--- a/lib/sqlalchemy/testing/profiling.py
+++ b/lib/sqlalchemy/testing/profiling.py
@@ -241,17 +241,26 @@ def function_call_count(variance=0.05, times=1, warmup=0):
     # likely due to the introduction of __signature__.
 
     from sqlalchemy.util import decorator
+    from sqlalchemy.util import deprecations
+    from sqlalchemy.engine import row
+    from sqlalchemy.testing import mock
 
     @decorator
     def wrap(fn, *args, **kw):
-        for warm in range(warmup):
-            fn(*args, **kw)
-
-        timerange = range(times)
-        with count_functions(variance=variance):
-            for time in timerange:
-                rv = fn(*args, **kw)
-            return rv
+
+        with mock.patch.object(
+            deprecations, "SQLALCHEMY_WARN_20", False
+        ), mock.patch.object(
+            row.LegacyRow, "_default_key_style", row.KEY_OBJECTS_NO_WARN
+        ):
+            for warm in range(warmup):
+                fn(*args, **kw)
+
+            timerange = range(times)
+            with count_functions(variance=variance):
+                for time in timerange:
+                    rv = fn(*args, **kw)
+                return rv
 
     return wrap