Fixed up the behavior of the :class:`_result.Row` object when dictionary
access is used upon it, meaning converting to a dict via ``dict(row)`` or
accessing members using strings or other objects i.e. ``row["some_key"]``
works as it would with a dictionary, rather than raising ``TypeError`` as
would be the case with a tuple, whether or not the C extensions are in
place. This was originally supposed to emit a 2.0 deprecation warning for
the "non-future" case using :class:`_result.LegacyRow`, and was to raise
``TypeError`` for the "future" :class:`_result.Row` class. However, the C
version of :class:`_result.Row` was failing to raise this ``TypeError``,
and to complicate matters, the :meth:`_orm.Session.execute` method now
returns :class:`_result.Row` in all cases to maintain consistency with the
ORM result case, so users who didn't have C extensions installed would
see different behavior in this one case for existing pre-1.4 style
code.

Therefore, in order to soften the overall upgrade scheme as most users have
not been exposed to the more strict behavior of :class:`_result.Row` up
through 1.4.6, :class:`_result.LegacyRow` and :class:`_result.Row` both
provide for string-key access as well as support for ``dict(row)``, in all
cases emitting the 2.0 deprecation warning when ``SQLALCHEMY_WARN_20`` is
enabled. The :class:`_result.Row` object still uses tuple-like behavior for
``__contains__``, which is probably the only noticeable behavioral change
compared to :class:`_result.LegacyRow`, other than the removal of
dictionary-style methods ``values()`` and ``items()``.

Also remove filters for result set warnings.

callcounts updated for 2.7/ 3.9, am pushing jenkins to use python 3.9
now

Fixes: #6218
Change-Id: Ia69b974f3dbc46943c57423f57ec82323c8ae63b

* remove the c version of distill params since it's actually slower than
the python one
* add a function to langhelpers to check if the cextensions are active
* minor cleanup to the OrderedSet implementation

Change-Id: Iec3d0c3f0f42cdf51f802aaca342ba37b8783b85

* ensure on python 2 correct cflags to fail on undefined
symbols take effect

* fail for implicit function declaration

* python 2 does not publish PyDict_GetItemWithError but has
it as _PyDict_GetItemWIthError but only as of Python 2.7.12

Change-Id: I007509afddf7f44ca64e52fa9140be39f815fa7a

Avoids using the call methods and instead uses the dict c interface.

Fixes: #5871
Change-Id: I7a1211104da319b0793a149f1a24f9f95c9f6630

Change-Id: Ic5bb19ca8be3cb47c95a0d3315d84cb484bac47c

The _execute_20 and exec_driver_sql methods should wrap
up the parameters so that they represent the single list / single
dictionary style of invocation into the legacy methods.  then
the before_ after_ execute event handlers should be receiving
the parameter dictionary as a single dictionary.   this requires
that we break out distill_params to work differently if event
handlers are present.

additionally, add deprecation warnings for old argument passing
styles.

Change-Id: I97cb4d06adfcc6b889f10d01cc7775925cffb116

Several weeks of using the future_select() construct
has led to the proposal there be just one select() construct
again which features the new join() method, and otherwise accepts
both the 1.x and 2.x argument styles.   This would make
migration simpler and reduce confusion.

However, confusion may be increased by the fact that select().join()
is different  Current thinking is we may be better off
with a few hard behavioral changes to old and relatively unknown APIs
rather than trying to play both sides within two extremely similar
but subtly different APIs.  At the moment, the .join() thing seems
to be the only behavioral change that occurs without the user
taking any explicit steps.   Session.execute() will still
behave the old way as we are adding a future flag.

This change also adds the "future" flag to Session() and
session.execute(), so that interpretation of the incoming statement,
as well as that the new style result is returned, does not
occur for existing applications unless they add the use
of this flag.

The change in general is moving the "removed in 2.0" system
further along where we want the test suite to fully pass
even if the SQLALCHEMY_WARN_20 flag is set.

Get many tests to pass when SQLALCHEMY_WARN_20 is set; this
should be ongoing after this patch merges.

Improve the RemovedIn20 warning; these are all deprecated
"since" 1.4, so ensure that's what the messages read.
Make sure the inforamtion link is on all warnings.
Add deprecation warnings for parameters present and
add warnings to all FromClause.select() types of methods.

Fixes: #5379
Fixes: #5284
Change-Id: I765a0b912b3dcd0e995426427d8bb7997cbffd51
References: #5159

This patch replaces the ORM execution flow with a
single pathway through Session.execute() for all queries,
including Core and ORM.

Currently included is full support for ORM Query,
Query.from_statement(), select(), as well as the
baked query and horizontal shard systems.  Initial
changes have also been made to the dogpile caching
example, which like baked query makes use of a
new ORM-specific execution hook that replaces the
use of both QueryEvents.before_compile() as well
as Query._execute_and_instances() as the central
ORM interception hooks.

select() and Query() constructs alike can be passed to
Session.execute() where they will return ORM
results in a Results object.   This API is currently
used internally by Query.   Full support for
Session.execute()->results to behave in a fully
2.0 fashion will be in later changesets.

bulk update/delete with ORM support will also
be delivered via the update() and delete()
constructs, however these have not yet been adapted
to the new system and may follow in a subsequent
update.

Performance is also beginning to lag as of this
commit and some previous ones.   It is hoped that
a few central functions such as the coercions
functions can be rewritten in C to re-gain
performance.  Additionally, query caching
is now available and some subsequent patches
will attempt to cache more of the per-execution
work from the ORM layer, e.g. column getters
and adapters.

This patch also contains initial "turn on" of the
caching system enginewide via the query_cache_size
parameter to create_engine(). Still defaulting at
zero for "no caching".   The caching system still
needs adjustments in order to gain adequate performance.

Change-Id: I047a7ebb26aa85dc01f6789fac2bff561dcd555d

This streamlines a bit for non-C implementations, however
also adds and tests behavioral contracts that mappings should
not allow integer or slice access and should behave like a
Python mapping in that it raises KeyError for an integer
and TypeError for a slice.   Py3/Py2/C/noC :)

References: #5340
Change-Id: Id3cef452dc8a526b8371c90c5ca2bbb240b25c26