Renamed "fixture_name" to "accessor_name" and made fixture names in the form "admin/users" be used as the key for the hashes @fixture_cache and @loaded_fixtures.

Previously the variable "fixture_name" here was getting a value of the form "admin_user", and this value was then used as the hash key.

Made the fixture's table name be taken from its model class whenever this class responds to table_name, instead of inferring it sometimes from the fixture's pass.

The previous behavior seemed buggy because it depended on whether the model class was passed as a constant or as a name string.

Improved Fixtures#initialize.

This solves an issue with set_fixture_class class method caused by create_fixtures method's overwriting passed to it fixture model classes, when the fixtures are "namespased": foo/bar or admin/users.

The idea is to use "foo/bar" string as the name and identifier of a
fixture file bar in directory foo.  The model class of the fixture is either set with set_fixture_class method, or otherwise inferred from its name using camelize method.

Also a bug is fixed in lines 487-489 when the table names were guessed by substitution from the fixture file names, ambiguously called  table_names, instead of being taken from fixture attributes.  Now they are taken from attributes.

I plan to submit another fix so that the fixture's table name (for
example foo_bar) be defined by the fixture's model whenever possible,
instead of inferring it from the fixture's name ("foo/bar").

Test using fixtures with random names and model names, that is not following naming conventions but using set_fixture_class instead.

It is expected that the table name be defined in the model, but this is not explicitly tested here.  This will need to be fixed.

This is the 'top level' connection, inherited by any models that include
ActiveRecord::Model or inherit from ActiveRecord::Base.

The problem: We need to be able to specify configuration in a way that
can be inherited to models that include ActiveRecord::Model. So it is
no longer sufficient to put 'top level' config on ActiveRecord::Base,
but we do want configuration specified on ActiveRecord::Base and
descendants to continue to work.

So we need something like class_attribute that can be defined on a
module but that is inherited when ActiveRecord::Model is included.

The solution: added ActiveModel::Configuration module which provides a
config_attribute macro. It's a bit specific hence I am not putting this
in Active Support or making it a 'public API' at present.

Fixed a bug in fixtures.rb where the table name was incorrectly inferred from the fixture path which was ambiguously called "table_name" but was also used as the fixture name.
Now, the "correct" table name is taken from an instance variable.

was "WHERE foo IN (1) OR foo IS NULL" before

index_name has been using the following expression

    "index_#{table_name}_on_#{Array.wrap(options[:column]) * '_and_'}"

since at least 2006 (bc7f2315), and that's how they come out in my DB.

Please check that this is correct before merging into master, perhaps
I'm misunderstanding the section I changed.

Revert "This conditions is required to work with database create task. 1.9.2 is having a bug with "Calling return within begin still executes else". "

No need to worry about 1.9.2 with master
This reverts commit fbf4bee6.

Make sure the table name of a model is reset in a test case after assigning ActiveRecord::Base.table_name_prefix and ActiveRecord::Base.table_name_suffix.

auto_explain_threshold_in_seconds should be a global config option so it can be shared between AR::Base and AR::Model