Section 5.6 Exercise 4 in Hartl Tutorial - ruby-on-rails

Question

I am trying to complete exercise 4 in Chapter 5 of the Hartl tutorial and I am getting these two errors when I run $bundle exec rake test:
Started
ERROR["test_layout_links", SiteLayoutTest, 2015-03-31 09:33:35 +0000]
test_layout_links#SiteLayoutTest (1427794415.88s)
NoMethodError: NoMethodError: undefined method `full_title' for # <SiteLayoutTest:0x00000006cee338>
test/integration/site_layout_test.rb:13:in `block in <class:SiteLayoutTest>'
test/integration/site_layout_test.rb:13:in `block in <class:SiteLayoutTest>'
ERROR["test_full_title_helper", ApplicationHelperTest, 2015-03-31 09:33:35 +0000]
test_full_title_helper#ApplicationHelperTest (1427794415.99s)
ArgumentError: ArgumentError: wrong number of arguments (0 for 1)
app/helpers/application_helper.rb:2:in `full_title'
test/helpers/application_helper_test.rb:5:in `block in <class:ApplicationHelperTest>'
app/helpers/application_helper.rb:2:in `full_title'
test/helpers/application_helper_test.rb:5:in `block in <class:ApplicationHelperTest>'
7/7: [====================================================================================================================] 100% Time: 00:00:00, Time: 00:00:00
Finished in 0.57888s
7 tests, 14 assertions, 0 failures, 2 errors, 0 skips
What do these errors mean, and how do I go about fixing the errors?
This is my test/integration/site_layout_test.rb code:
require 'test_helper'
class SiteLayoutTest < ActionDispatch::IntegrationTest
test "layout links" do
get root_path
assert_template 'static_pages/home'
assert_select "a[href=?]", root_path, count: 2
assert_select "a[href=?]", help_path
assert_select "a[href=?]", about_path
assert_select "a[href=?]", contact_path
get signup_path
assert_select "title", full_title("Sign up")
end
end
And this is my app/helpers/application_helper.rb code:
module ApplicationHelper
def full_title(page_title)
base_title = "Ruby on Rails Tutorial Sample App"
if page_title.empty?
base_title
else
" #{page_title} | #{base_title}"
end
end
end
This is my test/helpers/application_helper_test.rb file:
require 'test_helper'
class ApplicationHelperTest < ActionView::TestCase
test "full title helper" do
assert_equal full_title, "Ruby On Rails App"
assert_equal full_title("Help"), "Help | Ruby On Rails App"
end
end

Answer 1

What do these errors mean, and how do I go about fixing the errors?
NoMethodError: undefined method 'full_title' for #<SiteLayoutTest:0x00000006cee338>
test/integration/site_layout_test.rb:13
On line 13, you called a method that doesn't exist.
See http://ruby-doc.org/core-2.2.0/NoMethodError.html
ArgumentError: wrong number of arguments (0 for 1)
app/helpers/application_helper.rb:2:in 'full_title'
test/helpers/application_helper_test.rb:5
On line 5, you need to pass exactly one argument.
See http://ruby-doc.org/core-2.2.0/ArgumentError.html
See where the line numbers are in the error message?
I recommend reading an introductory ruby book, like http://ruby-doc.com/docs/ProgrammingRuby/ before (or while) learning rails.
Good luck!

Answer 2

In case anyone comes across the same error when they are going through the Michael Hartl 3rd edition...
I found the error in the app/helpers/application_helper.rb code. I needed to add an empty string for page_title, changing 'def full_title(page_title)' to 'def full_title(page_title= '')'
module ApplicationHelper
def full_title(page_title = '')
base_title = "Ruby on Rails Tutorial Sample App"
if page_title.empty?
base_title
else
"#{page_title} | #{base_title}"
end
end
end