Temping allows you to create arbitrary ActiveRecord models backed by a temporary SQL table for use in tests. You may need to do something like this if you're testing a module that is meant to be mixed into ActiveReord models without relaying on a concrete class.

Temping will use your existing database connection. If one does not exist, it will create and connect to an in-memory SQLite3 instance.

As we're using temporary tables all data will be dropped when the database connection is terminated.

The basic setup of a model involves calling create with a symbol that represents the class name of the model you wish to create. By default, this will create a temporary table with an id column.

Temping.create :dog

Dog.create => #<Dog id: 1>
Dog.table_name => "dogs"
Dog => Dog(id: integer)

Additional database columns can be specified via the with_columns method which uses Rails migration syntax:

Temping.create :dog do
  with_columns do |t|
    t.string :name
    t.integer :age, :weight
  end
end

Dog.create => #<Dog id: 1, name: nil, age: nil, weight: nil>

When a block is passed to create, it is evaluated in the context of the class. This means anything you do in an ActiveRecord model class body can be accomplished in the block including method definitions, validations, module includes, etc.

Temping.create :dog do
  validates :name, presence: true

  include Duckish

  with_columns do |t|
    t.string :name
    t.integer :age, :weight
  end

  def quack
    "arf!"
  end
end

Dog.create! => ActiveRecord::RecordInvalid: Validation failed: Name can"t be blank

codey = Dog.create! name: "Codey"
codey.quack => "arf!"

In your Gemfile:

gem "temping"

Tickets can be submitted by via GitHub issues.