We don't do anything with it, so even if the user pass it no warning is
print

Remove reference to global rails command in the docs

Switch to standardized argument name

We only need to call this method once.

Allow AR::Enum definitions with boolean values

Ruby 2.7 is not available yet.

Document how to add session middleware to an API app

Clear callback triggers when transaction completes

This commit will be squished into f4fbdb1b after maintainer's review.

The `_trigger_update_callback` and `_trigger_destroy_callback`
attributes were added in 9252da96 to
avoid running transactional callbacks when an attempt to modify a record
fails inside a transaction due to the record being invalid, for example.

However the values weren't being reset between transactions, which meant
they leaked from one transaction to another and caused false positives
where unsuccessful modifications still triggered callbacks. Clearing
them when a transaction commits or is rolled back fixes the problem.

Addresses some comments in original PR for docs on using session management middleware in API apps

Fix Ruby 2.7 warnings on `MiddlewareStackProxy`

This fixes the following warnings:

```
/rails/railties/lib/rails/railtie.rb:190: warning: Using the last argument as keyword parameters is deprecated; maybe ** should be added to the call
/rails/railties/lib/rails/application.rb:222: warning: The called method `config_for' is defined here
```

The following loop constantizes after logging.

Especially this is caused on `config.app_middleware.insert_after` in our
code base:

https://github.com/rails/rails/blob/2b9edb777b2a9567eac8e79e5dc44ce2ef28fe23/activerecord/lib/active_record/railtie.rb#L88-L90
https://github.com/rails/rails/blob/2b9edb777b2a9567eac8e79e5dc44ce2ef28fe23/activerecord/lib/active_record/migration.rb#L556-L557

This reverts commit ed78e964, reversing
changes made to eca6c273.

Use pg 1.2.0 to support Ruby 2.7

This pull request addresses 3 failures which expect no warnings. If
these tests executed with Ruby 2.7, all of them failed due to warnings
for tainted objects.

* How to create this commit:

```
% bundle update pg --conservative
```

* Background for this change

pg gem 1.2.0 https://rubygems.org/gems/pg/versions/1.2.0 has been released including https://github.com/ged/ruby-pg/pull/307
to support Ruby 2.7, showing warnings for tainted objects. Refer https://bugs.ruby-lang.org/issues/16131

* Steps to reproduce:

```
% cd activerecord
% ruby -v
ruby 2.7.0dev (2019-12-25T06:38:55Z master 75dca097b8) [x86_64-darwin19]
% bundle update --bundler

% ARCONN=postgresql bundle exec ruby -w -Itest test/cases/adapters/postgresql/referential_integrity_test.rb -n test_does_not_print_warning_if_no_invalid_foreign_key_exception_was_raised
% ARCONN=postgresql bundle exec ruby -w -Itest test/cases/adapters/postgresql/enum_test.rb -n test_no_oid_warning
% ARCONN=postgresql bundle exec ruby -w -Itest test/cases/adapters/postgresql/postgresql_adapter_test.rb -n test_only_warn_on_first_encounter_of_unrecognized_oid
```

* Actual results:

```
% ARCONN=postgresql bundle exec ruby -w -Itest test/cases/adapters/postgresql/referential_integrity_test.rb -n test_does_not_print_warning_if_no_invalid_foreign_key_exception_was_raised

Using postgresql
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:919: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.
... snip ...
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:259: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.
F

Failure:
PostgreSQLReferentialIntegrityTest#test_does_not_print_warning_if_no_invalid_foreign_key_exception_was_raised [test/cases/adapters/postgresql/referential_integrity_test.rb:73]:
expected no warnings but got:
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.
... snip ...
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.
/Users/yahonda/src/github.com/yahonda/rails/activesupport/lib/active_support/core_ext/object/try.rb:15: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.

rails test test/cases/adapters/postgresql/referential_integrity_test.rb:62

Finished in 0.052862s, 18.9172 runs/s, 56.7515 assertions/s.
1 runs, 3 assertions, 1 failures, 0 errors, 0 skips
%
```

```
% ARCONN=postgresql bundle exec ruby -w -Itest test/cases/adapters/postgresql/enum_test.rb -n test_no_oid_warning
Using postgresql
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:919: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.
... snip ...
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:259: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.
F

Failure:
PostgresqlEnumTest#test_no_oid_warning [test/cases/adapters/postgresql/enum_test.rb:76]:
Expected "/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:100: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:100: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:106: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:24: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n" to be blank?.

rails test test/cases/adapters/postgresql/enum_test.rb:72

Finished in 0.059806s, 16.7207 runs/s, 16.7207 assertions/s.
1 runs, 1 assertions, 1 failures, 0 errors, 0 skips
%
```

```
% ARCONN=postgresql bundle exec ruby -w -Itest test/cases/adapters/postgresql/postgresql_adapter_test.rb -n test_only_warn_on_first_encounter_of_unrecognized_oid
Using postgresql
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:919: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.
... snip ...
/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:259: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.
F

Failure:
ActiveRecord::ConnectionAdapters::PostgreSQLAdapterTest#test_only_warn_on_first_encounter_of_unrecognized_oid [test/cases/adapters/postgresql/postgresql_adapter_test.rb:372]:
Expected /\Aunknown OID \d+: failed to recognize type of 'regclass'\. It will be treated as String\.\n\z/ to match "/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:100: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb:20: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\nunknown OID 2205: failed to recognize type of 'regclass'. It will be treated as String.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:106: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:100: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:106: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:100: warning: rb_tainted_str_new_cstr is deprecated and will be removed in Ruby 3.2.\n/Users/yahonda/src/github.com/yahonda/rails/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb:106: warning: rb_tainted_str_new is deprecated and will be removed in Ruby 3.2.\n".

rails test test/cases/adapters/postgresql/postgresql_adapter_test.rb:363

Finished in 0.037451s, 26.7016 runs/s, 53.4031 assertions/s.
1 runs, 2 assertions, 1 failures, 0 errors, 0 skips
%
```

https://github.com/tzinfo/tzinfo/releases/tag/v1.2.6

If `AR::Enum` is used for boolean field, it would be not expected
behavior for us.

fixes #38075

Problem:

In case of using boolean for enum, we can set with string (hash key)
to instance, but we cannot set with actual value (hash value).

```ruby
class Post < ActiveRecord::Base
  enum status: { enabled: true, disabled: false }
end

post.status = 'enabled'
post.status # 'enabled'

post.status = true
post.status # 'enabled'

post.status = 'disabled'
post.status # 'disabled'

post.status = false
post.status # nil (This is not expected behavior)
```

After looking into `AR::Enum::EnumType#cast`, I found that `blank?`
method converts from false value to nil (it seems it may not intentional behavior).

In this patch, I improved that if it defines enum with boolean,
it returns reasonable behavior.

Use the single line editor in console test

It's a bit difficult to deal properly with IRB's multi line and color,
and I think we don't need to check it out in `rails console` tests.

Fix keyward arguments warning in `MiddlewareStack#build`

Make `LoadInterlockAwareMonitor` work in Ruby 2.7

This is an alternative of 6b633a28.

`ActionDispatch::Static` middleware requires to be passed `**kwargs`.

https://github.com/rails/rails/blob/0b3c710d35199d187dbfddaefbb9ab2752ea6498/railties/lib/rails/application/default_middleware_stack.rb#L27
https://github.com/rails/rails/blob/0b3c710d35199d187dbfddaefbb9ab2752ea6498/actionpack/lib/action_dispatch/middleware/static.rb#L112-L116

But `ActionDispatch::Session::CookieStore` middleware requires to be
passed actual `session_options` to `options.merge!(cookie_only: true)`
destructively.

(Ideally passed args should not be mutated, but for now the middleware
intentionally murate the args and testing that.)

https://github.com/rails/rails/blob/0b3c710d35199d187dbfddaefbb9ab2752ea6498/railties/lib/rails/application/default_middleware_stack.rb#L65
https://github.com/rails/rails/blob/0b3c710d35199d187dbfddaefbb9ab2752ea6498/actionpack/lib/action_dispatch/middleware/session/cookie_store.rb#L59-L61
https://github.com/rails/rails/blob/0b3c710d35199d187dbfddaefbb9ab2752ea6498/railties/test/application/configuration_test.rb#L1557-L1563
https://github.com/rails/rails/blob/0b3c710d35199d187dbfddaefbb9ab2752ea6498/railties/test/application/middleware/session_test.rb#L337-L341

To address both case, we need to evaluate args for building app in the
`use` method context (that method args in the context have last args
whether kwargs or hash).