If clear it before the test, the mail of the last executed test will not
be correctly cleared.
Therefore, executing the test with seed below will result in an error.
```
./bin/test -w --seed 55480
Run options: --seed 55480
# Running:
...........................................................................................................................................................F
Failure:
MailDeliveryTest#test_does_not_increment_the_deliveries_collection_on_error [/home/yaginuma/program/rails/master_y_yagi/rails/actionmailer/test/delivery_methods_test.rb:221]:
--- expected
+++ actual
@@ -1 +1 @@
-[]
+[#<Mail::Message:47011389364640, Multipart: false, Headers: <Date: Mon, 14 Aug 2017 07:48:40 +0900>, <From: test-sender@test.com>, <To: test-receiver@test.com>, <Message-ID: <5990d748ea5b2_29342ac1af8bcf40886f7@yaginuma.mail>>, <Subject: Test Subject>, <Mime-Version: 1.0>, <Content-Type: text/plain>, <Content-Transfer-Encoding: 7bit>>]
bin/test test/delivery_methods_test.rb:216
```
On the first request, ActionController::Base#action_methods computes
and memoized the list of available actions [1]. With this PR we move
this expensive operation into eager load step to reduce response time
of the first request served in production.
This also reduces the memory footprint when running on forking server
like Unicorn.
[1] a3813dce9a/actionpack/lib/abstract_controller/base.rb (L66-L77)
Setting delivery_job on a mailer class will cause MessageDelivery to use
the specified job instead of ActionMailer::DeliveryJob:
class MyMailer < ApplicationMailer
self.delivery_job = MyCustomDeliveryJob
...
end
* Allow a default value to be declared for class_attribute
* Convert to using class_attribute default rather than explicit setter
* Removed instance_accessor option by mistake
* False is a valid default value
* Documentation
Without this, Action Mailer doesn't work like it used to on version 4.
The following snippet fails since version 5:
> require 'action_mailer'
> ActionMailer::Base
NameError: uninitialized constant ActiveSupport::Rescuable
Currently `ActiveSupport::Duration` implicitly converts to a seconds
value when used in a calculation except for the explicit examples of
addition and subtraction where the duration is the receiver, e.g:
>> 2 * 1.day
=> 172800
This results in lots of confusion especially when using durations
with dates because adding/subtracting a value from a date treats
integers as a day and not a second, e.g:
>> Date.today
=> Wed, 01 Mar 2017
>> Date.today + 2 * 1.day
=> Mon, 10 Apr 2490
To fix this we're implementing `coerce` so that we can provide a
deprecation warning with the intent of removing the implicit coercion
in Rails 5.2, e.g:
>> 2 * 1.day
DEPRECATION WARNING: Implicit coercion of ActiveSupport::Duration
to a Numeric is deprecated and will raise a TypeError in Rails 5.2.
=> 172800
In Rails 5.2 it will raise `TypeError`, e.g:
>> 2 * 1.day
TypeError: ActiveSupport::Duration can't be coerced into Integer
This is the same behavior as with other types in Ruby, e.g:
>> 2 * "foo"
TypeError: String can't be coerced into Integer
>> "foo" * 2
=> "foofoo"
As part of this deprecation add `*` and `/` methods to `AS::Duration`
so that calculations that keep the duration as the receiver work
correctly whether the final receiver is a `Date` or `Time`, e.g:
>> Date.today
=> Wed, 01 Mar 2017
>> Date.today + 1.day * 2
=> Fri, 03 Mar 2017
Fixes#27457.
ActionMailer::Base#instrument_name and
ActionController::Base#instrument_name will be frequently called once
caching is enabled. So it's better to freeze them instead of create new
string on every call.
Also, the instrument name in #instrument_fragment_cache will usually
be "write_fragment.action_controller" or
"read_fragment.action_controller". So freezing them might also gain some
performance improvement. We have done something like this in other places:
https://github.com/rails/rails/blob/master/actionview/lib/action_view/template.rb#L348
The raw_source method is documented as returning the exact value that
was used to create the body; mutating it breaks that contract.
Additionally, if the value used to create the body is blank, raw_source
returns a frozen string which causes the interceptor to raise an error.
