Added a ``**kw`` argument to the :meth:`.DeclarativeMeta.__init__` method.
This allows a class to support the :pep:`487` metaclass hook
``__init_subclass__``.  Pull request courtesy Ewen Gillies.

Fixes: #5357
Closes: #5363
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5363
Pull-request-sha: 0ad05a768316cba03a4d312ab39d3e8fbca7ac54

Change-Id: I1654befe9eb1c8b8e7fc0784bdbe64284614f0ea

Note the PR has a few remaining doc linking issues
listed in the comment that must be addressed separately.

Signed-off-by: aplatkouski <5857672+aplatkouski@users.noreply.github.com>
Closes: #5371
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5371
Pull-request-sha: 7e7d233cf3a0c66980c27db0fcdb3c7d93bc2510

Change-Id: I9c36e8d8804483950db4b42c38ee456e384c59e3

Replaces a wide array of Sphinx-relative doc references
with an abbreviated absolute form now supported by
zzzeeksphinx.

Change-Id: I94bffcc3f37885ffdde6238767224296339698a2

zzzeeksphinx 1.1.2 in git can now convert short
prefix names in a configured lookup to fully qualified module
names, so that
we can have succinct and portable pyrefs
that still resolve absolutely.
It also includes a formatter that will format all pyrefs
in a fully consistent way regardless of the package path,
by unconditionally removing all package tokens but always
leaving class names in place including for methods, which
means we no longer have to deal with tildes in pyrefs.

The most immediate goal of the absolute prefixes is
that we have lots of
"ambiguous" names that appear in muliple places, like select(),
ARRAY, ENUM etc.   With the incoming future packages there
is going to be lots of name overlap so it is necessary
that all names eventually use absolute package paths
when Sphinx receives them.

In multiple stages, pyrefs will be converted using the
zzzeeksphinx tools/fix_xrefs.py tool so that doclinks can
be made absolute using symbolic prefixes.

For this review, the actual search and replace of symbols
is not performed, instead some general cleanup to prepare
the docs as well as a lookup file used by the tool
to do the conversion.   this relatively small patch will
be backported
with appropriate changes to 1.3, 1.2, 1.1 and the tool
can then be run on each branch individually.  We are shooting
for almost no warnings at all for master (still a handful
I can't figure out which don't seem to have any impact)
, very few for 1.3,
and for 1.2 / 1.1 we hope for a significant reduction
in warnings.

Overall for all versions pyrefs should
always point to the correct target, if they are in fact
hyperlinked.  it's better for a ref to go nowhere and
be plain text than go to the wrong thing.  Right now,
hundreds of API links are pointing to the wrong thing
as they are ambiguous names such as refresh(), insert(),
update(), select(), join(), JSON etc. and Sphinx sends these all
to essesntially random destinations among as many as five
or six possible choices per symbol.  A shorthand system
that allows us to use absolute refs without having
to type out a full blown absoulte module is the only
way this is going to work, and we should ultimately
seek to abandon any use of prefix dot for lookups.  Everything
should be on an underscore token so at the very least the module
spaces can be reorganized without having to search and replace
the entire documentation every time.

Change-Id: I484a7329034af275fcdb322b62b6255dfeea9151

- Remove deprecated method ``get_primary_keys` in the :class:`.Dialect` and
  :class:`.Inspector` classes.
- Remove deprecated event ``dbapi_error`` and the method ``ConnectionEvents.dbapi_error`.
- Remove support for deprecated engine URLs of the form ``postgres://``.
- Remove deprecated dialect ``mysql+gaerdbms``.
- Remove deprecated parameter ``quoting`` from :class:`.mysql.ENUM`
  and :class:`.mysql.SET` in the ``mysql`` dialect.
- Remove deprecated function ``comparable_property``. and function
  ``comparable_using`` in the declarative extension.
- Remove deprecated function ``compile_mappers``.
- Remove deprecated method ``collection.linker``.
- Remove deprecated method ``Session.prune`` and parameter ``Session.weak_identity_map``.
  This change also removes the class ``StrongInstanceDict``.
- Remove deprecated parameter ``mapper.order_by``.
- Remove deprecated parameter ``Session._enable_transaction_accounting`.
- Remove deprecated parameter ``Session.is_modified.passive``.
- Remove deprecated class ``Binary``. Please use :class:`.LargeBinary`.
- Remove deprecated methods ``Compiled.compile``, ``ClauseElement.__and__`` and
  ``ClauseElement.__or__`` and attribute ``Over.func``.
- Remove deprecated ``FromClause.count`` method.
- Remove deprecated parameter ``Table.useexisting``.
- Remove deprecated parameters ``text.bindparams`` and ``text.typemap``.

- Remove boolean support for the ``passive`` parameter in ``get_history``.
- Remove deprecated ``adapt_operator`` in ``UserDefinedType.Comparator``.

Fixes: #4643
Change-Id: Idcd390c77bf7b0e9957907716993bdaa3f1a1763

The string argument accepted as the first positional argument by the
:func:`.relationship` function when using the Declarative API is no longer
interpreted using the Python ``eval()`` function; instead, the name is dot
separated and the names are looked up directly in the name resolution
dictionary without treating the value as a Python expression.  However,
passing a string argument to the other :func:`.relationship` parameters
that necessarily must accept Python expressions will still use ``eval()``;
the documentation has been clarified to ensure that there is no ambiguity
that this is in use.

Fixes: #5238
Change-Id: Id802f403190adfab0ca034afe2214ba10fd9cfbb

Introduced a modules registry to register modules that should be lazily loaded
in the package init. This ensures that they are in the system module cache,
avoiding potential thread safety issues as when importing them directly
in the function that uses them. The module registry is used to obtain
these modules directly, ensuring that the all the lazily loaded modules
are resolved at the proper time

This replaces dependency_for decorator and the dependencies decorator logic,
removing the need to pass the resolved modules as arguments of the
decodated functions and removes possible errors caused by linters.

Fixes: #4689
Fixes: #4656
Change-Id: I2e291eba4297867fc0ddb5d875b9f7af34751d01

Applied an explicit "cause" to most if not all internally raised exceptions
that are raised from within an internal exception catch, to avoid
misleading stacktraces that suggest an error within the handling of an
exception.  While it would be preferable to suppress the internally caught
exception in the way that the ``__suppress_context__`` attribute would,
there does not as yet seem to be a way to do this without suppressing an
enclosing user constructed context, so for now it exposes the internally
caught exception as the cause so that full information about the context
of the error is maintained.

Fixes: #4849
Change-Id: I55a86b29023675d9e5e49bc7edc5a2dc0bcd4751

(zzzeek:) For some reason I thought that threading.Lock() still did
not support context managers, at least in Python 2, however this
does not seem to be the case.

Co-authored-by: Mike Bayer <mike_mp@zzzcomputing.com>
Closes: #5069
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/5069
Pull-request-sha: efeac06dda5afdbe33abcf9b27c8b5b5725c8444

Change-Id: Ic64fcd99cd587bc70b4ecc5b45d8205b5c76eff2