Ruby - uninitialized constant - ruby-on-rails

Question

I have this 4 classes, the code is simple but when I try to generate, it returns an error like
in `<main>': uninitialized constant PruebasUnitarias (NameError)
The code is this and I dont know what is wrong, I thought it was because of requires, but I have all in one document and still crash.
class Complejo
def initialize (real, imaginario)
#real = real
#imaginario = imaginario
end
def sumar (complejo)
#real = #real + complejo.real
#imaginario = #imaginario + complejo.imaginario
end
attr_reader :real, :imaginario
end
class Prueba
def assertCierto(valor)
return valor
end
def assertFalso(valor)
return valor
end
def assertIgual(num1, num2)
if(num1 == num2)
return true
end
return false
end
def assertDistinto(num1, num2)
if(num1 != num2)
return true
end
false
end
def assertNil param
if (param == nil)
return true
end
false
end
def assertContiene(param1, param2)
param1.include?(param2)
end
end
class PruebasUnitarias::Prueba
def run
metodos = self.methods
if(self.respond_to? :inicializacion)
self.inicializacion
end
end
end
class PruebaComplejo < PruebasUnitarias::Prueba
def inicializacion
#c1 = Complejo.new(3,5)
#c2 = Complejo.new(1,-1)
end
def prueba_suma
#c1.sumar(#c2)
assertIgual(#c1.real, 4)
assertIgual(#c1.imaginario, 4)
end
def prueba_suma_cero
#c2.sumar(Complejo.new(0,0))
assertCierto(#c2.real==1)
assertCierto(#c2.imaginario==-1)
end
def prueba_suma_nula
#c2.sumar(nil)
assertIgual(#c2.real, 1)
assertIgual(#c2.imaginario, -1)
end
def imprimir (complejo)
puts "complejo: #{complejo.real}, #{complejo.imaginario}i"
end
end

Answer 1

You have to declare the module before you can put a class in it. Try this instead:
module PruebasUnitarias
class Prueba
...
end
end
class PruebaComplejo < PruebasUnitarias::Prueba
...
end

Answer 2

Just as a note about your programming style, you need to think in simpler terms when it comes to testing your values. Consider these changes:
def assertCierto(valor)
valor
end
def assertFalso(valor)
valor
end
def assertIgual(num1, num2)
num1 == num2
end
def assertDistinto(num1, num2)
num1 != num2
end
def assertNil param
param == nil
end
It's not necessary to use an if test to see if something is equal or not equal and then return true or false. The test itself does that so simply compare the values and let Ruby return the result by default.
1 == 1 # => true
1 == 2 # => false
1 != 1 # => false
1 != 2 # => true
Also, use snake_case for method names, not camelCase. ItsAReadabilityThing:
def assert_cierto(valor)
def assert_falso(valor)
def assert_igual(num1, num2)
def assert_distinto(num1, num2)
def assert_nil param