RSpec - неверное число аргументов (0 за 1..2)

Question

Учитывая этот код:

class Game 

    def self.game_board 
    return [[][][]] 
    end 
    def self.empty_output 
    '_|_|_'+ 
    '_|_|_'+ 
    ' | |' 
    end 
end 

и эти тесты:

describe 'It should display a grid' do 
    it 'should have empty output' do 
    Game.empty_output.should == 
    '_|_|_'+ 
    '_|_|_'+ 
    ' | |' 
    end 
    it 'should have an empty array for the game ' do 
    Game.game_board.should == 
    [[][][]] 
    end 
end 

почему испытания не который пытается вернуть массив массивов с ошибкой

.F 

Failures: 

    1) "It should display a grid should be empty 
    Failure/Error: return [[][][]] 
    ArgumentError: 
     wrong number of arguments (0 for 1..2) 
    # ./checkers_rspec.rb:4:in `[]' 
    # ./checkers_rspec.rb:4:in `game_board' 
    # ./checkers_rspec.rb:24:in `block (2 levels) in <top (required)>' 

Finished in 0.00121 seconds 
2 examples, 1 failure 

Answer 1

[[][][]] should hae been [[],[],[]] in both cases.