Have copied code correctly yet ruby tells me there is a name error

here is the code i have written after following the Test Driven Development video precisely:

require 'minitest/autorun' require 'minitest/spec'

$:.unshift File.expand_path(File.dirname(File) + '/..')

require 'lib/bank_account'

describe BankAccount do subject { BankAccount.new("Nick") }

it "should be a bank account instance" do subject.must_be_instance_of BankAccount end

it "should have a name" do subject.must_respond_to 'name' end

it "should initialize with a name" do bank_account = BankAccount.new("Nick") bank_account.name.must_equal 'Nick' end

it "should have transactions" do subject.must_respond_to 'transactions' end end

the error it gives out is:

MadelynsMiniMac-2:bank_account madelynpapineau$ ruby spec/bank_account_spec.rb spec/bank_account_spec.rb:4:in <main>': undefined local variable or methodFile' for main:Object (NameError)

can someone explain what I'm doing wrong please? THank You