Why the object references are not correctly passed in this RSpec script? - ruby

Question

I have to say I am new both to Ruby and to RSpec. Anyway I completed one RSpec script but after refactoring it failed. Here is the original working version:
describe Site do
browser = Watir::Browser.new :ie
site = Site.new(browser, "http://localhost:8080/site")
it "can navigate to any page at the site" do
site.pages_names.each do |page_name|
site.goto(page_name)
site.actual_page.name.should eq page_name
end
end
browser.close
end
and here is the modified version - I wanted to have reported all the pages which were visited during the test:
describe Site do
browser = Watir::Browser.new :ie
site = Site.new(browser, "http://localhost:8080/site")
site.pages_names.each do |page_name|
it "can navigate to #{page_name}" do
site.goto(page_name)
site.actual_page.name.should eq page_name
end
end
browser.close
end
The problem in the latter case is that site gets evaluated to nil within the code block associated with 'it' method.
But when I did this:
...
s = site
it "can navigate to #{page_name}" do
s.goto(page_name)
s.actual_page.name.should eq page_name
end
...
the nil problem was gone but tests failed with the reason "browser was closed"
Apparently I am missing something very basic Ruby knowledge - because the browser reference is not working correctly in modified script. Where did I go wrong? What refactoring shall be applied to make this work?
Thanks for your help!

Answer 1

It's important to understand that RSpec, like many ruby programs, has two runtime stages:
During the first stage, RSpec loads each of your spec files, and executes each of the describe and context blocks. During this stage, the execution of your code defines your examples, the hooks, etc. But your examples and hooks are NOT executed during this stage.
Once RSpec has finished loading the spec files (and all examples have been defined), it executes them.
So...trimming down your example to a simpler form, here's what you've got:
describe Site do
browser = Watir::Browser.new :ie
it 'does something with the browser' do
# do something with the browser
end
browser.close
end
While visually it looks like the browser instance is instantiated, then used in the example, then closed, here's what's really happening:
The browser instance is instantiated
The example is defined (but not run)
The browser is closed
(Later, after all examples have been defined...) The example is run
As O.Powell's answer shows, you can close the browser in an after(:all) hook to delay the closing until after all examples in this example group have run. That said, I'd question if you really need the browser instance at example definition time. Generally you're best off lazily creating resources (such as the browser instance) when examples need them as they are running, rather than during the example definition phase.

Answer 2

I replicated your code above using fake classes for Site and Watir. It worked perfectly. My only conclusion then is that the issue must lie with either one of the above classes. I noticed the Site instance only had to visit one page in your first working version, but has to visit multiple pages in the non working version. There may be an issue there involving the mutation happening inside the instance.
See if this makes a difference:
describe Site do
uri = "http://localhost:8080/site"
browser = Watir::Browser.new :ie
page_names = Site.new(browser, uri).page_names
before(:each) { #site = Site.new(browser, uri) }
after(:all) { browser.close }
pages_names.each do |page_name|
it "can navigate to #{page_name}" do
#site.goto(page_name)
#site.actual_page.name.should eq page_name
end
end
end