Add assert_enqueued_email_with to ActionMailer::TestHelper

activerecord: Remove a redundant mutation tracker

Nested scaffold should be fine

Align `bin/update`'s Yarn usage with `bin/setup`

[ci skip]

Ensure `HashWithIndifferentAccess#transform_keys` to return `HashWithIndifferentAccess`

Currently, `#transform_values`, `#select` and `#reject` return instance
of `HashWithIndifferentAccess`. But `#transform_keys` returns instance
of Hash. This behavior is a bit confusing.

I think that `HashWithIndifferentAccess#transform_keys` should also return
instance of `HashWithIndifferentAccess` as well as other methods.

Since #29301, `arel_attribute` respects a custom table name.

Use `ActiveRecord::ConnectionAdapters::Quoting.quote` to quote bounds for a PostgreSQL range

PostgreSQL 9.1+ introduced range types, and Rails added support for
using this datatype in ActiveRecord. However, the serialization of
`PostgreSQL::OID::Range` was incomplete, because it did not properly
quote the bounds that make up the range. A clear example of this is a
`tsrange`.

Normally, ActiveRecord quotes Date/Time objects to include the
milliseconds. However, the way `PostgreSQL::OID::Range` serialized its
bounds, the milliseconds were dropped. This meant that the value was
incomplete and not equal to the submitted value.

An example of normal timestamps vs. a `tsrange`. Note how the bounds
for the range do not include their milliseconds (they were present in
the ruby Range):

    UPDATE "iterations" SET "updated_at" = $1, "range" = $2 WHERE
    "iterations"."id" = $3
    [["updated_at", "2017-09-23 17:07:01.304864"],
    ["range", "[2017-09-23 00:00:00 UTC,2017-09-23 23:59:59 UTC]"],
    ["id", 1234]]

`PostgreSQL::OID::Range` serialized the range by interpolating a
string for the range, which works for most cases, but does not work
for timestamps:

    def serialize(value)
      if value.is_a?(::Range)
        from = type_cast_single_for_database(value.begin)
        to = type_cast_single_for_database(value.end)
        "[#{from},#{to}#{value.exclude_end? ? ')' : ']'}"
      else
        super
      end
    end

    (byebug) from = type_cast_single_for_database(value.begin)
    2010-01-01 13:30:00 UTC

    (byebug) to = type_cast_single_for_database(value.end)
    2011-02-02 19:30:00 UTC

    (byebug) "[#{from},#{to}#{value.exclude_end? ? ')' : ']'}"
    "[2010-01-01 13:30:00 UTC,2011-02-02 19:30:00 UTC)"

@sgrif (the original implementer for Postgres Range support) provided
some feedback about where the quoting should occur:

  Yeah, quoting at all is definitely wrong here. I'm not sure what I
  was thinking in 02579b56, but what this is doing is definitely in the
  wrong place. It should probably just be returning a range of
  subtype.serialize(value.begin) and subtype.serialize(value.end), and
  letting the adapter handle the rest.

`Postgres::OID::Range` now returns a `Range` object, and
`ActiveRecord::ConnectionAdapters::PostgreSQL::Quoting` can now encode
and quote a `Range`:

    def encode_range(range)
      "[#{type_cast(range.first)},#{type_cast(range.last)}#{range.exclude_end? ? ')' : ']'}"
    end

    ...

    encode_range(range)
    #=> "['2010-01-01 13:30:00.670277','2011-02-02 19:30:00.745125')"

This commit includes tests to make sure the milliseconds are
preserved in `tsrange` and `tstzrange` columns

It is also used in `BlockTestCase`.

`abstract_unit.rb` in actionview was copied from actionpack in the
commit eb23754e. But some part is never used for actionview's tests.

These are no longer used since 66736c8e.

Change :github git source for bug report templates

Because the reflection doesn't have `foreign_type` unless the
association is a polymorphic association.

:github source uses `git://` url by default, `https://` is recommended.
See http://bundler.io/v1.15/guides/git.html#security

We do the same in our `Gemfile` and templates.

Add a space to RefineryCMS in Engine guide [ci skip]

I do not want to set the expectation that any enumerable object should
behave this way, but this case in particular comes up frequently enough
that I'm caving on this one.

Fixes #30684.

PERF: Partially recover some performance when preloading. 

Fix typo in 'find_in_batches' example

Fixed broken `bundle exec rake install`

Benchmark Script:
```
require 'active_record'
require 'benchmark/ips'

ActiveRecord::Base.establish_connection(ENV.fetch('DATABASE_URL'))
ActiveRecord::Migration.verbose = false

ActiveRecord::Schema.define do
  create_table :users, force: true do |t|
    t.string :name, :email
    t.integer :topic_id
    t.timestamps null: false
  end

  create_table :topics, force: true do |t|
    t.string :title
    t.timestamps null: false
  end
end

attributes = {
  name: 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
  email: 'foobar@email.com'
}

class Topic < ActiveRecord::Base
  has_many :users
end

class User < ActiveRecord::Base
  belongs_to :topic
end

100.times do
  User.create!(attributes)
end

users = User.first(50)

Topic.create!(title: 'This is a topic', users: users)

Benchmark.ips do |x|
  x.config(time: 10, warmup: 5)

  x.report("preload") do
    User.includes(:topic).all.to_a
  end
end
```

Before:
```
Calculating -------------------------------------
             preload    40.000  i/100ms
-------------------------------------------------
             preload    407.962  (± 1.5%) i/s -      4.080k
```

After:
```
alculating -------------------------------------
             preload    43.000  i/100ms
-------------------------------------------------
             preload    427.567  (± 1.6%) i/s -      4.300k
```

Remove unused fixtures

`about_yml_plugins` is no longer used since 82b9b151

* According to the official website, it seems that "RefineryCMS" is "Refinery CMS".
* See at: http://www.refinerycms.com/

Preload digest/sha2 to avoid thread safe error.

Respect quiet option in all process of `rails new` command

Fix minor CodeClimate issue

Based on, yet closes https://github.com/rails/rails/pull/30708

Fix the session test by properly truncating the legacy encryption
key for cbc encryption. Borrowed straight from 👆.

Fix the cookies test a little differently than the PR. Basically
keep every config within the config block.

[ Michael Coyne & Kasper Timm Hansen ]

I got this error in production using Puma in multi-threaded mode:

```
RuntimeError: Digest::Base cannot be directly inherited in Ruby
from active_support/security_utils.rb:23:in `variable_size_secure_compare'
from active_support/security_utils.rb:23:in `hexdigest'
from active_support/security_utils.rb:23:in `digest'
```

Looks like Digest uses const_missing to load Digest::SHA256 (https://github.com/ruby/ruby/blob/trunk/ext/digest/lib/digest.rb#L8)

- https://bugs.ruby-lang.org/issues/9494
- https://github.com/ruby/ruby/commit/c02fa39463a0c6bf698b01bc610135604aca2ff4

New missing backquotes [ci skip]

PERF: Restore memoization when preloading associations.

Benchmark Script

```
require 'active_record'
require 'benchmark/ips'
require 'ruby-prof'
require 'memory_profiler'
require 'byebug'

ActiveRecord::Base.establish_connection(ENV.fetch('DATABASE_URL'))
ActiveRecord::Migration.verbose = false

ActiveRecord::Schema.define do
  create_table :users, force: true do |t|
    t.string :name, :email
    t.integer :topic_id
    t.timestamps null: false
  end

  create_table :topics, force: true do |t|
    t.string :title
    t.timestamps null: false
  end
end

attributes = {
  name: 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.',
  email: 'foobar@email.com'
}

class Topic < ActiveRecord::Base
  has_many :users
end

class User < ActiveRecord::Base
  belongs_to :topic
end

100.times do
  User.create!(attributes)
end

users = User.first(50)

Topic.create!(title: 'This is a topic', users: users)

Benchmark.ips do |x|
  x.config(time: 10, warmup: 5)

  x.report("preload") do
    User.includes(:topic).all.to_a
  end
end
```

Before

```
Calculating -------------------------------------
             preload    26.000  i/100ms
-------------------------------------------------
             preload    265.347  (± 3.0%) i/s -      2.652k
```

After

```
Calculating -------------------------------------
             preload    39.000  i/100ms
-------------------------------------------------
             preload    406.053  (± 1.7%) i/s -      4.095k
```