Tests failing: "after submission" -- undefined local variable or method 'submit' - ruby-on-rails

Question

I'm doing the exercises for Michael Hartls Rails tutorial, chapter 7, section 7.6. I am attempting to make tests for "after submission," but get the error:
Failure/Error: before { click_button submit }
NameError:
undefined local variable or method `submit' for #<RSpec::Core::ExampleGroup::Nested_4::Nested_4:0x007f8289dede70>
I don't know how to fix this. I have capybara installed, and all of my other tests work.
Any suggestions?
Here is a link to the chapter
and my code for rspec:
require 'spec_helper'
describe "UserPages" do
subject { page }
describe "profile page" do
let(:user) { FactoryGirl.create(:user) }
before { visit user_path(user) }
it { should have_content(user.name) }
it { should have_title(user.name) }
end
describe "signup page" do
before { visit signup_path }
it { should have_content('Sign up') }
it { should have_title(full_title('Sign up'))}
end
describe "signup" do
before { visit signup_path }
let(:submit) { "Create my account" }
describe "with invalid information" do
it "should not create a user" do
expect { click_button submit }.not_to change(User, :count)
end
end
describe "with valid information" do
before do
fill_in "Name", with: "Example User"
fill_in "Email", with: "user#example.com"
fill_in "Password", with: "foobar"
fill_in "Confirmation", with: "foobar"
end
it "should create a user" do
expect { click_button submit }.to change(User, :count).by(1)
end
end
end
describe "after submission" do
before { visit signup_path }
before { click_button submit }
it { should have_title('Sign up') }
it { should have_content('error') }
end
end

Answer 1

Per other questions about this stretch of Hartl's book, are you missing a
let(:submit) { "Sign up" }
?
And you should not be learning Rails by learning Capybara -> Cucumber, but that's the fashion these days...