method-deprecator.md

MethodDeprecator

Basics

MethodDeprecator is an implementation of class ActiveSupport::Deprecation. ActiveSupport is the Ruby on Rails component providing core extensions for basic Ruby functionality. Ruby on Rails requires all of this functionality by default.

In addition, every Class has as a superclass a Module. ActiveSupport provides an extension to Module, which defines a method deprecate.

Therefore, deprecate can be called from every class and module inside the Sharetribe application that inherits from those two aforementioned classes.

By default, deprecate will print a notification about method being deprecated in the next Rails version. It takes as a named parameter an optional :deprecator, where we can define our own functionality. This is provided by MethodDeprecator.

MethodDeprecator is included in config/application.rb and is therefore usable everywhere in the app.

Examples

class LaunchControl
  def launch_apollo
    puts "Apollo, lift-off!!"
  end

  def launch_shuttle
    puts "Shuttle, lift-off!"
  end

  def launch_soyuz
    puts "Союз, отрываться"
  end


  deprecate_method launch_apollo: "Apollo hasn't gone to the moon for a while, use launch_soyuz instead.",
                   launch_shuttle: "Shuttle isn't in service anymore. Use launch_soyuz instead.",
                   deprecator: MethodDeprecator.new
end


lctl = LaunchControl.new
lctl.launch_apollo   # => DEPRECATION WARNING: launch_apollo is deprecated and will be removed in future. |
                     #    Apollo hasn't gone to the moon for a while, use launch_soyuz instead. (called from <main> at (pry):41
lctl.launch_shuttle  # => DEPRECATION WARNING: launch_apollo is deprecated and will be removed in future. |
                     #    Shuttle isn't in service anymore. Use launch_soyuz instead. (called from <main> at (pry):43