DZone Snippets: testing code

load all fixtures

remvee (Remco van 't Veer) — Fri, 18 Jan 2008 19:01:16 GMT

In some test cases I need all my fixtures to be loaded. To make this easier, add the following to test/test_helper.rb:



class Test::Unit::TestCase

  def self.all_fixtures

    Dir[File.dirname(__FILE__) + "/fixtures/*.yml"].each do |f|

      fixtures File.basename(f, '.yml')

    end

  end



  ..

end

and in your tests use it as follows:



class FooTest < Test::Unit::TestCase

  all_fixtures



  ..

end

Happy testing!

Make Time "Stand Still" in Ruby

bshow (Bob Showalter) — Thu, 15 Nov 2007 21:36:47 GMT

When writing tests, it's sometimes difficult to test results of methods that use current time. Two calls to Time.now can give different results and cause test failures. Here is some code that lets you execute a block during which Time.now will return a consistent value:



class Time



  # this code adds a Time.freeze method to make time "stand still"

  # during execution of a block. This can be helpful during testing of

  # methods that depend on Time.new or Time.now

  #

  # Example:

  #

  #   Time.freeze do

  #      puts Time.new.to_f

  #      # ... do stuff; real time passes

  #      puts Time.new.to_f     # outputs same time as above

  #   end

  #   # ... time returns to normal

  #

  # An optional Time object may be passed to freeze to a specific time:

  #

  #   Time.freeze(Time.at(2007, 11, 15)) do

  #      # ...

  #   end

  #

  # While inside the block, Time.frozen? will return true



  class << self



    def now

      @time || orig_new

    end



    alias_method :orig_freeze, :freeze

    alias_method :orig_new, :new

    alias_method :new, :now



    # makes time "stand still" during execution of a block. if no time is

    # supplied, the current time is used. While in the block, Time.new and

    # Time.now will always return the "frozen" value.

    def freeze(time = nil)

      raise "A block is required" unless block_given?

      begin

        prev = @time

        @time = time || now

        yield

      ensure

        @time = prev

      end

    end



    def frozen?

      !@time.nil?

    end



  end

end

rcov rake task for rails project

akbloom (Andrew Bloom) — Tue, 11 Sep 2007 16:13:45 GMT

This task will create a folder (doc/coverage) then run all of your tests and produce HTML with code coverage information in that folder. If you are on a mac it will even open the index.html file up for you automatically



# this requires the RCOV gem to be installed on your system

namespace :test do

  desc "Generate code coverage with rcov"

  task :coverage do

    rm_f "doc/coverage/coverage.data"

    rm_f "doc/coverage"

    mkdir "doc/coverage"

    rcov = %(rcov --rails --aggregate doc/coverage/coverage.data --text-summary -Ilib --html -o doc/coverage test/**/*_test.rb)

    system rcov

    system "open doc/coverage/index.html" if PLATFORM['darwin']

  end

end

Helper for testing default routes generated by a resource in Ruby on Rails

grantneufeld (Grant Neufeld) — Mon, 10 Sep 2007 12:46:23 GMT

These methods test that the routes for resources defined in routes.rb are working as expected. Call them from your functional (controller) tests.

Add the following 3 methods to test/test_helper.rb (updated for Rails 1.2.5 which no longer uses semicolons as a separator for the edit action):



# Test for routes generated by map.resource (singular).

def assert_routing_for_resource(controller, skip=[], nesting=[])

  routes = [

    ["new",'/new',{},:get], ["create",'',{},:post],

    ["show",'',{},:get], ["edit",'/edit',{},:get],

    ["update",'',{},:put], ["destroy",'',{},:delete]

    ]

  check_resource_routing(controller, routes, skip, nesting)

end

# Test for routes generated by map.resources (plural).

def assert_routing_for_resources(controller, skip=[], nesting=[])

  routes = [

    ["index",'',{},:get], ["new",'/new',{},:get], ["create",'',{},:post],

    ["show",'/1',{:id=>'1'},:get], ["edit",'/1/edit',{:id=>'1'},:get],

    ["update",'/1',{:id=>'1'},:put], ["destroy",'/1',{:id=>'1'},:delete]

    ]

  check_resource_routing(controller, routes, skip, nesting)

end



# Check that the expected paths will be generated by a resource, and that

# the expected params will be generated by paths defined by a resource.

# routes is array of [action, url string after controller, extra params].

def check_resource_routing(controller, routes, skip=[], nesting=[])

  # set a prefix for nested resources

  prefix = nesting.join('s/1/')

  unless prefix.blank?

    prefix += "s/1/"

  end

  # Add params for nested resources.

  # For each 'nest', include a ":nest_id=>'1'" param.

  params = {}

  nesting.each do |param|

    params["#{param}_id".to_sym] = '1'

  end

  # Test each of the standard resource routes.

  routes.each do |pair|

    unless skip.include? pair[0]

      assert_generates("/#{prefix}#{controller}#{pair[1]}",

        {:controller=>controller,

        :action=>pair[0]}.merge(pair[2]).merge(params), {}, {},

        "Failed generation of resource route for action #{pair[0]} /#{prefix}#{controller}#{pair[1]}")

      assert_recognizes(

        {:controller=>controller,

          :action=>pair[0]}.merge(pair[2]).merge(params),

        {:path=>"/#{prefix}#{controller}#{pair[1]}", :method=>pair[3]},

        {}, "Failed to recognize resource route for path #{pair[3]}:/#{prefix}#{controller}#{pair[1]}")

    end

  end

end

EXAMPLES

You can specify actions to 'skip' (if you have a special route for that action).
If using nested resources, set the nesting array (use singular strings).

So, if you have the following in routes.rb:



map.make_thing '/make', :controller=>'things', :action=>'new'

map.resources :nests do |nest|

  nest.resources :things

end

map.resource :foo

then you can use the following in things_controller_test.rb:



def test_resource_routing

  assert_routing_for_resources 'things', ['new'], ['nest']

  assert_routing_for_resource 'foo'

end

Testing for Exception message in Rails

sikelianos (Zeke Sikelianos) — Wed, 18 Jul 2007 14:39:53 GMT



e = assert_raise(RuntimeError) { my_code_that_raises }

assert_match(/Error message here/i, e.message)..

Custom headers in Rails tests

rodfrey (Rod Frey) — Sat, 07 Apr 2007 16:49:18 GMT

From time to time you may need to set headers in your functional tests that aren't supported by the @request object. I had to set up my request with Basic authentication.

Add an extension to the TestRequest class in the test/test_helper.rb file:



class ActionController::TestRequest 

  def set_header(name, value)

    @env[name] = value

  end

end

Then set values as required in your functional test.



def test_index

  @request.set_header "HTTP_AUTHORIZATION", "Basic " + Base64.encode64('testuser:testpass')

  get :index

  assert_response :success

  assert_template "index"

end

In Place Testing for Ruby methods

peter (Peter Cooperx) — Mon, 02 Apr 2007 08:13:22 GMT

This is something kinda experimental I'm working on. Testing is cool, but I hate that it's separate from my code. Perhaps that's stupidity on my part, but I wanted to see if there's a way to bring the lowest level of testing directly into the class..



module InPlaceTesting

  def self.included(klass)

    old_method_added = klass.method(:method_added)

    new_method_added = lambda do |m|

      @@current_method = m

      old_method_added.call m

    end

    

    # Next line inspired by http://utils.ning.com/ruby/dbc.rb by Brian McCallister and Martin Traverso

    (class << klass; self; end).send :define_method, :method_added, new_method_added

    

    class << klass

      def given(*args)

        self.new.send @@current_method, *args

      end

      def method_should(message, params)

        unless params[:return] == params[:when]

          puts "\"#{@@current_method}\" fails to #{message} (returns #{params[:when]} instead of #{params[:return]})"

        end

      end

    end

    

  end

  

end



class DumbClass

  include InPlaceTesting



  def add(x,y) 

    x + y

  end

  method_should "add 5 and 4", :return => 9, :when => given(5, 4)



  def subtract(x,y) 

    x - y

  end 

  method_should "subtract 5 from 14", :return => 9, :when => given(14,5)

  

  def increment(x)

    x + 1

  end

  method_should "increment 12", :return => 13, :when => given(12)

end

test

bugmenot (BugMeNot) — Thu, 07 Dec 2006 17:47:00 GMT

// description of your code here



	if (in_array($r["type"], Array(1, print str_replace("; ;","",(get_part_of_text($desc, 300)));

	else { $sql->query("SELECT of.phone FROM offers o, offices of

			WHERE o.office_id=of.id AND o.id=".$r["id"]);

		list($office_phone) = $sql->getrow(

print (str_replace("; ;","",(get_part_of_text($desc,300))))."
Contacts:".$office_phone;

	}

#post method in tests with a different controller

moneypenny () — Tue, 24 Oct 2006 18:54:12 GMT

I wanted a #login method in test_helper that would allow me to easily login from any of my functional tests. However, the #post method won't allow you to set a different controller than the one in the @controller instance variable that's defined in your test's #setup. Well, by looking at how the #process method works, you can see that it just grabs the controller from @controller. Redefine that, and you're good to go:

old_controller = @controller

@controller = LoginController.new

post(

  :attempt_login,

  {:user => {:name => 'joe', :password => 'password'}}

)

@controller = old_controller

If you have several login methods, such as a #login_admin and #login_regular, you could make a wrapper to reduce duplication:

def wrap_with_controller( new_controller = LoginController )

  old_controller = @controller

  @controller = new_controller.new

  yield

  @controller = old_controller

end



def login_admin

  wrap_with_controller do

    post(

      :attempt_login,

      {:user => {:name => 'root', :password => 'password'}}

    )

  end

end



def login_regular

  wrap_with_controller do

    post(

      :attempt_login,

      {:user => {:name => 'joe', :password => 'password'}}

    )

  end

end

Create YAML test fixtures from database in Rails

jswizard (JavaScript Wizard) — Mon, 04 Sep 2006 01:48:31 GMT

As found at http://media.pragprog.com/titles/fr_rr/code/CreateFixturesFromLiveData/lib/tasks/extract_fixtures.rake



desc 'Create YAML test fixtures from data in an existing database.  

Defaults to development database.  Set RAILS_ENV to override.'



task :extract_fixtures => :environment do

  sql  = "SELECT * FROM %s"

  skip_tables = ["schema_info"]

  ActiveRecord::Base.establish_connection

  (ActiveRecord::Base.connection.tables - skip_tables).each do |table_name|

    i = "000"

    File.open("#{RAILS_ROOT}/test/fixtures/#{table_name}.yml", 'w') do |file|

      data = ActiveRecord::Base.connection.select_all(sql % table_name)

      file.write data.inject({}) { |hash, record|

        hash["#{table_name}_#{i.succ!}"] = record

        hash

      }.to_yaml

    end

  end

end