Method: PropCheck::Generators.instance

Defined in:

lib/prop_check/generators.rb

.instance(klass, *args, **kwargs) ⇒ Object

Generates an instance of klass using args and/or kwargs as generators for the arguments that are passed to klass.new

## Example:

Given a class like this:

 class User
   attr_accessor :name, :age
   def initialize(name: , age: )
     @name = name
     @age = age
   end

   def inspect
     "<User name: #{@name.inspect}, age: #{@age.inspect}>"
   end
 end

>> user_gen = Generators.instance(User, name: Generators.printable_ascii_string, age: Generators.nonnegative_integer)
>> user_gen.sample(3, rng: Random.new(42)).inspect
=> "[<User name: \"S|.g\", age: 10>, <User name: \"rvjj\", age: 10>, <User name: \"7\\\"5T!w=\", age: 5>]"

# File 'lib/prop_check/generators.rb', line 861

def instance(klass, *args, **kwargs)
  tuple(*args).bind do |vals|
    fixed_hash(**kwargs).map do |kwvals|
      if kwvals == {}
        klass.new(*vals)
      elsif vals == []
        klass.new(**kwvals)
      else
        klass.new(*vals, **kwvals)
      end
    end
  end
end