Nov 15, 2018

We are all legacy code - Part 3

In Part 2 we were able to get our code running locally. Today we’ll be looking at the automated tests.

Getting started

I’m not sure this series of posts is really a “follow along” type of series. To be honest I’m largely blogging my steps so I have some documentation for myself should I need to dive into this code again. Having said that, it is certainly possible to follow along.

If doing so, you can continue with the code from part 2. Or you can clone the code as it stood after part 2.

Clone the Repo

If cloning the code from GitHub:

Terminal
git clone -b part-02-app-running-locally https://github.com/riebeekn/wmcgy2 budget-app
cd budget-app

If getting the code from GitHub, we also will need to repeat our steps to set our local Ruby version and run bundle install.

Terminal
rbenv local 2.2.4
Terminal
bundle install

And with that, we are good to go.

Today’s objective

The goal for today is pretty simple, get the tests running and passing.

Let’s get at it!

Test time!

First let’s create a branch for getting the tests up and running.

Terminal
git checkout -b get-tests-running

Getting the tests running

Let’s see if we get lucky and everything runs a-ok right off the bat.

First off we need to set-up our test database:

Terminal
bundle exec rake db:test:prepare

And with that we’ll let the tests rip:

Terminal
bundle exec rspec spec/

… or not! Looks like we have an error!

This turns out to be another Gemfile issue, we need to include the test-unit Gem. This change goes into the :development, :test group of the Gemfile:

/Gemfile
group :development, :test do
  gem 'rspec-rails', '~>2.12.1'
  gem 'test-unit', '~> 3.0'
end

Let’s give it another go.

Terminal
bundle exec rspec spec/

And with that we have a running test suite! Granted we are getting a lot of warning messages, but I suppose that is to be expected seeing how we are running off some pretty old versions of various Gems.

57 failures, not too bad!

Looking through our failures we also can see that fixing our tests might result in some of our bugs going away. For instance we have a failing test around transaction deletion:

And also a number of failures with the Category tests:

Anyway, time to try to turn that red into green!

Getting the tests passing

Before we start diving into our actual test code, one thing I want to explore is what version of Ruby and Rails we should be running. Perhaps an upgrade will resolve a few of our failing tests.

Figuring out what version of Ruby and Rails we should be running

Given that our site is a Rails 3 application, we want to be running the latest version of Rails 3 and the latest version of Ruby that supports Rails 3.

Now… in any case there is any doubt about the fact that we are dealing with full on legacy code here, Rails 3 reached it’s end of life in the summer of 2016, with the last release (3.2.22.5) coming out in September of 2016.

The last version of Ruby that supports Rails 3 is Ruby 2.3.6. Ruby 2.3 is currently outside of normal maintenance and is only receiving security maintenance. It’s end of life date is scheduled for early 2019… so not so far away!

Given the above we likely want to upgrade to Rails 4 and ideally even Rails 5… but those will be tasks for another day if we so choose. We’re going to concentrate on getting the application back working under Rails 3.

So to summarize we want to be running Ruby 2.3.6 and Rails 3.2.22.5.

Let’s update our Gemfile.

/Gemfile
source 'https://rubygems.org'
ruby '2.3.6'

gem 'rails', '3.2.22.5'
...
...

If we now run bundle install we’ll encounter a familiar problem.

Terminal
bundle install

Mismatched Ruby versions, so let’s set our Ruby version via rbenv.

Terminal
rbenv local 2.3.6

Now let’s run bundle install again.

Terminal
bundle install

We’ll see that this is one of those instances when we need to use bundle update.

So let’s do just that.

Terminal
bundle update rails

With those changes, let’s hit up our tests again.

Terminal
bundle exec rspec spec/

This gives us a new error:

After a bit of Googling, I determined this was down to another Gem incompatibility, this time with rspec. So we need to update our rspec version in our Gemfile.

/Gemfile
group :development, :test do
  gem 'rspec-rails', '~>2.99'
  gem 'test-unit', '~> 3.0'
end

Now let’s try the tests again.

Terminal
bundle exec rspec spec/

And we have running tests!

And even better most of our pesky warning messages have gone away and we only have 37 failing tests now!

What’s more, it appears our deletion test is no longer failing and our category tests are also no longer failing. Does this mean the category page bug and the transaction deletion bug have been fixed by the updated Ruby and Rails versions?

Having a quick look at our delete and category bugs

Let’s have a quick look, we’ll fire up the server.

Terminal
rails s

When we login with the user we created in part 2 and check out the category page… we see:

It works!

What about if we try to delete a transaction?

It also works!

Getting our failures to pass

Ok, so this is fantastic! We still have a bunch of failing tests however, let’s get back to fixing them up.

Looking at our failures, it appears we have three problematic spec files, user_spec, transaction_spec and transactions_spec. Let’s start off by examining the errors in user_spec.

Fixing the user_spec tests

Let’s run just the user_spec tests and see what failures we get.

Terminal
bundle exec rspec spec/models/user_spec.rb

5 failures, let’s tackle them one by one, we’ll start with the failing test on line 221. We can run an individual test by specifying the line number in rspec.

Terminal
bundle exec rspec spec/models/user_spec.rb:221

So it looks like an object that we are expecting to have a value is empty. Our test code looks like:

/spec/models/user_spec.rb
describe "send activation email" do
  let(:user) { FactoryGirl.create(:user) }

  it "delivers email to user" do
    user.send_activation_email
    last_email.should_not be_nil
    last_email.to.should include(user.email)
  end

We can see the failure happens on the 3rd line of the test where we are testing that the last_email item is not nil.

Looking through our code base, the last_email value is defined in a mailer_macro file.

/spec/support/mailer_macros.rb
module MailerMacros
  def last_email
    ActionMailer::Base.deliveries.last
  end

  def reset_email
    ActionMailer::Base.deliveries = []
  end
end

So the last_email value is taken from the ActionMailer deliveries array.

When running under the test environment, instead of sending an actual email, any sent emails are placed in the deliveries array. This is configured in our test.rb environment configuration file.

/config/environments/test.rb
...
...
# Tell Action Mailer not to deliver emails to the real world.
# The :test delivery method accumulates sent emails in the
# ActionMailer::Base.deliveries array.
config.action_mailer.delivery_method = :test
config.action_mailer.raise_delivery_errors = false
...
...

So everything looks like it should work, but for whatever reason the deliveries array is not being populated. After running the test, if we look in the /log/test.log file we can see the email is getting sent.

So this is a bit of a puzzle. I spent a fair bit of time looking into what might be going on, but wasn’t able to figure things out… so considering the email gets into the logs ok, I made the decision to ignore this test. Not a very auspicious start! Ignoring tests because they are failing is not what I would consider a best practice! In this case it’s what we’re going with however.

The 2nd failing test also has the same issue, so I’ve ignored it as well.

The updated test definitions at line 221 and 248 are:

/spec/models/user_spec.rb
it "delivers email to user", :skip => "Skipping this test as ActionMailer::Base.deliveries.last is always empty, but the email shows up in the test log, not sure what the issue is" do
  user.send_activation_email
  last_email.should_not be_nil
  last_email.to.should include(user.email)
end

...
...

it "delivers email to user", :skip => "Skipping this test as ActionMailer::Base.deliveries.last is always empty, but the email shows up in the test log, not sure what the issue is" do
  user.send_password_reset_email
  last_email.should_not be_nil
  last_email.to.should include(user.email)
end

Now when we run these tests we get 2 pending results and the output includes the text from our skip messages.

Terminal
bundle exec rspec spec/models/user_spec.rb:221:248

Let’s have a look at our remaining 3 failing tests. It looks like they all have to do with the code we use to grab the data for our income by category report.

The errors all look the same, the expected value of “Pay”, is coming up as “Other”.

Looking at the first test, the code is:

/spec/models/user_spec.rb
it "should show all transactions when range is empty" do
  income = @user.income_by_category_and_date_range('')
  income[0]["name"].should eq("Pay")
  income[0]["sum"].should eq("100.00")
  income[1]["name"].should eq("Other")
  income[1]["sum"].should eq("50.00")
end

Based on the error message and the test code, I am guessing we have a situation where the values are coming in at different array positions than what we are expecting. Likely the implementation code does not specify an ordering and these tests were just passing via luck of the draw (or luck of the ordering?) previously.

Sure enough looking at the implementation the return values are not ordered.

/app/models/user.rb …line 212
def income_by_category_and_date_range(range)
  transactions.
    select("name, SUM(amount)").
    joins("LEFT JOIN categories on categories.id = transactions.category_id").
    where(where_clause_for_transactions_by_date_and_category(false, range)).
    group("name")
end
...
...

So let’s add an order clause:

/app/models/user.rb …line 212
def income_by_category_and_date_range(range)
  transactions.
    select("name, SUM(amount)").
    joins("LEFT JOIN categories on categories.id = transactions.category_id").
    where(where_clause_for_transactions_by_date_and_category(false, range)).
    group("name").
    order("name")
end

Now that there is a fixed order for the data coming back, we need to update our tests to reflect this order (i.e. the ordering will be alphabetical by name, so the “Other” value will be first, the “Pay” value second). The updated tests are:

/spec/models/user_spec.rb …line 503
describe "income by category and date range" do
  it "should show all transactions when range is empty" do
    income = @user.income_by_category_and_date_range('')
    income[0]["name"].should eq("Other")
    income[0]["sum"].should eq("50.00")
    income[1]["name"].should eq("Pay")
    income[1]["sum"].should eq("100.00")
  end

  it "should display the correct items when range is one day ago" do
    range = "31 Dec 2012:TO:31 Dec 2012"
    income = @user.income_by_category_and_date_range(range)
    income[0]["name"].should eq("Other")
    income[0]["sum"].should eq("25.00")
    income[1]["name"].should eq("Pay")
    income[1]["sum"].should eq("75.00")
  end

  it "should display the correct items when range is one year ago" do
    range = "01 Jan 2012:TO:31 Dec 2012"
    income = @user.income_by_category_and_date_range(range)
    income[0]["name"].should eq("Other")
    income[0]["sum"].should eq("25.00")
    income[1]["name"].should eq("Pay")
    income[1]["sum"].should eq("100.00")
  end

end

We should have all the user_spec tests passing now… except for our 2 skipped tests of course.

Terminal
bundle exec rspec spec/models/user_spec.rb

Fantastic!

Let’s run all our tests and see where we are at.

Terminal
bundle exec rspec spec/

We have 2 remaining spec files with issues, and our change to user.rb may have caused a few new test failures as we have 34 failures. Prior to our user_spec changes we had 37 failures. 37 - 5 should bring us down to 32 failures, maybe the ordering clause has caused something else to go wonky.

In anycase, let’s move onto our next problematic model test, which is models/transaction_spec.rb

Fixing the transaction_spec tests

If we run just the transaction_spec tests we see that the entire suite is failing!

Terminal
bundle exec rspec spec/models/transaction_spec.rb

Having a glance at the test code, it looks like we are checking for the attributes of the transaction model, and these are all failing.

/spec/models/transaction_spec.rb
describe Transaction do
  before { @transaction = FactoryGirl.build(:transaction) }

  subject { @transaction }

  it { should respond_to(:description) }
  it { should respond_to(:date) }
  it { should respond_to(:amount) }
  it { should respond_to(:is_debit) }
  it { should respond_to(:category_id)
  ...
  ...

Running a single failing test we can see it looks like we may have an issue with our factory class.

Terminal
bundle exec rspec spec/models/transaction_spec.rb:23

Let’s have a look at the relevent factory code.

/spec/factories.rb
factory :transaction do
  sequence(:description)  { |n| "Description #{n}" }
  date { rand(100.days).ago }
  amount { 1 + rand(100) }
  is_debit true
  category
  user
end

The line that seems to be causing the issue is date { rand(100.days).ago }.

Looking at this code, it seems the closing parenthesis could be in the wrong place. Perhaps the previous versions of Rails/Ruby we were running allowed this syntax, but it looks a little wrong. I think the argument to rand should just be 100, not 100.days.

So let’s update the code:

/spec/factories.rb
factory :transaction do
  sequence(:description)  { |n| "Description #{n}" }
  date { rand(100).days.ago }
  amount { 1 + rand(100) }
  is_debit true
  category
  user
end

And give that a try.

Terminal
bundle exec rspec spec/models/transaction_spec.rb:23

Success!

So this likely has solved many of our failing tests, let’s re-run the full transaction_spec suite.

Terminal
bundle exec rspec spec/models/transaction_spec.rb

Sweet, that fixed them all!

Let’s run all our tests and see where we are at.

Terminal
bundle exec rspec spec/

It seems like we now have a fully passing suite of tests! The issue with factories.rb must have not only fixed the model/transaction_spec.rb tests but also the failing requests/transactions_spec.rb tests!

Also note our 2 pending tests display our skip messages to remind us why we’ve skipped them.

Fantastic! We can now merge our changes into our refactoring branch and remove our current working branch.

Terminal
git commit -am "got tests running and passing"
git checkout 2018-update-and-refactor
git merge get-tests-running
git branch -d get-tests-running

Summary

It’s been a bit of a struggle but we’ve managed to get the code running and the tests all passing (sorta’, we have those 2 pending tests that are a bit of a mystery). Even better, in the process we managed to fix 2 of the major bugs we had identified. This is some good progress! Next time we’ll start off by making sure we can deploy our code to a test Heroku instance and then tackle some more issues.

Thanks for reading and I hope you enjoyed the post!

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