From: Ryan Leavengood <mrcode@...>
Date: 2005-05-11T08:17:12+09:00
Subject: Re: Testing a user application

Vincent Foley wrote:
>
> Ryan Levengood suggested in another thread that I use mock objects for
> my testing purposes, but I don't understand clearly how they work.

I'm back with your example. To use this, change the initialize for
LiveJournalClient to this:

  def initialize(username, hpassword, &block)
    @username, @password = username, hpassword
    if block
      @server = block.call
    else
      @server = XMLRPC::Client.new("www.livejournal.com",
"/interface/xmlrpc", 80)
    end
  end

Here is the new test_ljclient.rb:

require "lib/ljclient"
require "test/unit"
require "digest/md5"

class MockServer
  attr_reader :method, :hash
  def initialize
    @exception = nil
  end

  def call(method, hash={})
    @method = method
    @hash = hash
    if @exception
      raise @exception.new('test', 'test')
    end
  end

  def do_raise(exception)
    @exception = exception
  end
end

class TestLiveJournalClient < Test::Unit::TestCase
  def initialize(name)
    super(name)
    @username = "test"
    @password = Digest::MD5.hexdigest("test")
    @client = create_client(@username, @password)
  end

  def create_client(username, password)
    LiveJournalClient.new(username, password) do
      @server = MockServer.new
    end
  end

  def test_login
    assert_nothing_raised(Exception) { @client.login }
    assert_equal('LJ.XMLRPC.login', @server.method)
    assert_equal(@username, @server.hash[:username])
    assert_equal(@password, @server.hash[:hpassword])

    bad_login = create_client("aosidoasndoiashd908h12", "")
    @server.do_raise(XMLRPC::FaultException)
    # Really this XMLRPC exception should be mapped to another
    # exception, like RJournal::InvalidLoginException
    assert_raise(XMLRPC::FaultException) { bad_login.login }

    bad_password = create_client(@username, "")
    @server.do_raise(XMLRPC::FaultException)
    # Same here, except it should be RJournal::InvalidPasswordException
    assert_raise(XMLRPC::FaultException) { bad_password.login }
  end

  def test_post
    subject = 'This is a subject'
    event = 'This is an event'
    assert_nothing_raised { @client.post(subject, event) }
    assert_equal('LJ.XMLRPC.postevent', @server.method)
    assert_equal(@username, @server.hash[:username])
    assert_equal(@password, @server.hash[:hpassword])
    assert_equal(subject, @server.hash[:subject])
    assert_equal(event, @server.hash[:event])
    # The other parts of the hash should also be tested
  end
end