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Учитывая модель, в которой вызывается обратный вызов throw(:abort) , как можно определить, какой обратный вызов выполнил действие, не изменяя сами обратные вызовы?

Например, следующая модель…

 class OddDuck < ApplicationRecord
  before_save :random_abort_1
  before_save :random_abort_2

  private

  def random_abort_1
    if Random.rand(2) == 1
      throw(:abort)
    end
  end

  def random_abort_2
    if Random.rand(2) == 1
      throw(:abort)
    end
  end
end
 

… иногда не удается сохранить …

 $ rails c
Running via Spring preloader in process 81303
Loading development environment (Rails 5.0.0.1)
irb(main):001:0> OddDuck.create!
   (0.1ms)  begin transaction
   (0.1ms)  rollback transaction
ActiveRecord::RecordNotSaved: Failed to save the record
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:152:in `save!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/validations.rb:50:in `save!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/attribute_methods/dirty.rb:30:in `save!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:324:in `block in save!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:395:in `block in with_transaction_returning_status'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:232:in `block in transaction'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/transaction.rb:189:in `within_new_transaction'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/connection_adapters/abstract/database_statements.rb:232:in `transaction'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:211:in `transaction'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:392:in `with_transaction_returning_status'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/transactions.rb:324:in `save!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/suppressor.rb:45:in `save!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activerecord-5.0.0.1/lib/active_record/persistence.rb:51:in `create!'
    from (irb):1
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/console.rb:65:in `start'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/console_helper.rb:9:in `start'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:78:in `console'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/railties-5.0.0.1/lib/rails/commands.rb:18:in `<top (required)>'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:293:in `require'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:293:in `block in require'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:259:in `load_dependency'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:293:in `require'
    from /Users/alice/Desktop/site/bin/rails:9:in `<top (required)>'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:287:in `load'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:287:in `block in load'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:259:in `load_dependency'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/activesupport-5.0.0.1/lib/active_support/dependencies.rb:287:in `load'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /Users/alice/.rbenv/versions/2.3.1/lib/ruby/2.3.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from -e:1:in `<main>'
 

… но из обратной трассировки не совсем очевидно, какой обратный вызов вызвал прерывание.

throw также принимает необязательное возвращаемое значение, поэтому вы можете использовать его, если вам нужно знать обратный вызов, который вызвал throw .

throw(tag [, obj])
Передает управление в конец активного catch блока, ожидающего tag . Возникает UncaughtThrowError , если catch для tag . Необязательный второй параметр предоставляет возвращаемое значение для catch блока, которое в противном случае используется по умолчанию nil .
https://ruby-doc.org/core-2.4.1/Kernel.html#method-i-throw

Например:

 def random_abort_1
  if Random.rand(2) == 1
    throw(:abort, __method__)
  end
end
 

Вернется random_abort_1 .