describe Gobstones::Parser, "function definitions" do

  it "parses a function without args and a single return" do
    func_return = ReturnFromFunction.new [42.to_gbs_num]

    func_def = Function.new 'just42', no_arguments, empty_body, func_return

    expect('function just42() { return (42) }').
      to be_parsed_as(:definition).and_return(func_def)
  end

  it "parses a function with some args" do
    args = VarTuple.new ['firstArg'.to_var_name, 'secondArg'.to_var_name, 'thirdArg'.to_var_name]
    return_st = ReturnFromFunction.new [verde, PuedeMover.new(norte)]
    func_def = Function.new 'myCoolFunction', args, empty_body, return_st

    expect('function myCoolFunction (firstArg, secondArg, thirdArg) {
  return (Verde, puedeMover(Norte))
}').to be_parsed_as(:definition).and_return(func_def)
  end

  it "parses a function with some statements" do
    args = VarTuple.new ['arg'.to_var_name]
    body = CommandBlock.new [Poner.new(verde)]
    return_st = ReturnFromFunction.new [true_value]
    func_def = Function.new 'myFunc', args, body, return_st

    expect('function myFunc(arg)
{
  Poner(Verde)
  return (True)
}').to be_parsed_as(:definition).and_return(func_def)
  end

  it "does not parse a function without a valid identifier" do
    expect('function MyWrongFunc() { return(True) }').
      to be_parsed_as(:definition).and_fail
  end

  it "does not parse a function without a return statement" do
    expect('function myFuncWithoutReturn() { }').
      to be_parsed_as(:definition).and_fail
  end

end