Dont

Easily deprecate methods.

Installation

Add this line to your application's Gemfile:

gem 'dont'

And then execute:

$ bundle

Or install it yourself as:

$ gem install dont

Usage

class Shouter
  include Dont::WithWarn

  def shout(msg)
    msg.upcase
  end

  def scream(msg)
    shout(msg)
  end
  # Indicate that we want to deprecate the scream method, and that you should
  # use "shout" instead. The :use option can be any string or symbol.
  dont_use :scream, use: :shout
end

# Logs "DEPRECATED: Don't use Shouter#scream. It's deprecated in favor of shout.",
# before executing the method.
Shouter.new.scream("hello")

With a custom handler

# Register a deprecation handler.
# Anything that responds to `.call(deprecation)` will work.
LOGGER = Logger.new
DeprecationLogger = Dont.register_handler(:logger, ->(deprecation) { LOGGER.warn(deprecation.message) })
class Shouter
  include DeprecationLogger

  def shout(msg)
    msg.upcase
  end

  def scream(msg)
    shout(msg)
  end
  dont_use :scream, use: :shout
end

# Logs "DEPRECATED: Don't use Shouter#scream. It's deprecated in favor of shout.", 
# before executing the method.
Shouter.new.scream("hello")

Raising exceptions in development

# The :exception deprecation handler is provided by default.
# It raises an exception whenever the method is called, which is handy in
# test or development mode.
class Person
  include Dont::WithException

  attr_accessor :firstname
  attr_accessor :first_name

  dont_use :firstname, use: :first_name
end
Person.new.firstname # => fails with Dont::DeprecationError

Using the Rails logger

# in config/initializers/dont.rb
Dont.register_handler(:rails_logger, ->(deprecation) { 
  Rails.logger.warn(deprecation.message) 
})
DontLogger = Dont.new(:rails_logger)

# in app/models/comment.rb
class Comment < ActiveRecord::Base
  include DontLogger # as defined in the initializer
  
  # We want to use `body` instead of `description` from now on
  alias_attribute :description, :body
  dont_use :description, use: :body
end

comment = Comment.new
comment.description
# => works, but with a deprecation warning: "DEPRECATED: Don't use Comment#description. It's deprecated in favor of body."

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/datacamp/dont. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.