Behavior Driven Development Using Visual Studio 2010 And SpecFlow

1. Behavior Driven DevelopmentUsing Visual Studio 2010 AndSpecFlow Ivan Pavlović, Hive Studios Visual C# MVP, MCT, CSM paki@hive-studios.com http://msforge.net/blogs/paki http://twitter.com/ipavlovi

2. Agenda • Little bit of slides, a lot of examples • What is BDD • Language • Tools • Demos

3. Types of Test • Unit testing • Acceptance / Customer testing • Integration testing • Performance testing • Regression testing

4. BehaviourDrivenDevelopment • One of agile development techniques • Specification driven by examples • Clear communication between domain experts, developers, testers and customers BDD is a second-generation, outside-in, pull-based, multiple-stakeholder, multiple-scale, high-automation, agile methodology. It describes a cycle of interactions with well-defined outputs, resulting in the delivery of working, tested software that matters. - Dan North (http://dannorth.net/)

5. Gherkin • DomainSpecificLanguage • Easy to understand by customers • Simple sintax, few keywords • Feature • Background • Scenario, Scenario Outline • Given,When, Then • Localized on 35+ languages

6. Example 1: Feature: Some descriptive text of what is desired 2: In order to realize a named business value 3: As an explicit system actor 4: I want to gain some beneficial outcome which furthers the goal 5: 6: Scenario: Some determinable business situation 7: Given some precondition 8: And some other precondition 9: When some action by the actor 10: And some other action 11: And yet another action 12: Then some testable outcome is achieved 13: And something else we can check happens too 14: 15: Scenario: A different situation 16: ...

7. Real example Feature: Serve coffee In order to earn money Customers should be able to buy coffee at all times Scenario: Buy last coffee Given there are 1 coffees left in the machine And I have deposited 1$ When I press the coffee button Then I should be served a coffee

8. Tools • Tools are generating *.feature files • Cucumber – Ruby, http://cukes.info/ • SpecFlow– .NET, http://specflow.org • Nunit, MSTest, MBUnit… • …a lot of other tools

9. Putting All The Pieces Together • User writes features & scenarios, clarify • SpecFlow generates one test per scenario • Developer runs test • Developer implements missing steps • Developer writes production code • Move to the next scenario

10. Mapping Step Definitions … 7: Given some precondition 8: And some other precondition 9: When some action by the actor 10: Thensome testable outcome is achieved [Given(@„some precondition")] public void SomePrecondition() { … do something… } [Given(@„some other precondition")] public void SomePrecondition() { … do something… } [When(@„some action by the actor")] public void SomePrecondition() { … do something… } [Then(@”some verifiable result”)] Public void VerifyResult() { … do assert… } Test Run

11. Step Arguments - RegEx … 7: GivenI have 5 apples 8: AndI eat 2 of them 9: Whensomeone asks how many apples I do have 10: Then I should answer “3 apples” [Given(@„I have (.*) apples")] public void SomePrecondition(intnumberOfApples) { … do something… } [Given(@„ I eat (.*) of them")] public void SomePrecondition(intnumberOfEatenApples) { … do something… } [When(@„ someone asks how many apples I do have")] public void SomePrecondition() { … do something… } [Then(@” I should answer \“(.*) apples\””)] Public void VerifyResult(int expected) { … do assert of expected … }

12. Table Parameters Scenario: Posting a validentry Given I am on the postingpage And I havefilledout the form as follows | Label | Value | | Yourname | Jakob | | Yourcomment | Das ist gut! | When I click the buttonlabelled "Post" Then I should be on the guestbookpage Andthe guestbookentriesincludes the following | Name | Comment | Posted date | | Jakob | Das ist gut! | (within last minute) | [Given(@"I havefilledout the form as follows")] publicvoidFillFormAsFollows(TechTalk.SpecFlow.Tabletable) { foreach(var row in table.Rows) { ….. Do something … } }

13. Scenario outline - refactoring Scenario: TC1 Add two numbers Given I have entered 1 into the calculator And I have entered 2 into the calculator When I press add Then the result should be 3 on the screen Scenario: TC2 Add two numbers Given I have entered 2 into the calculator And I have entered 2 into the calculator When I press add Then the result should be 4 on the screen

14. Scenario outline - refactoring Scenario Outline: TC5Given I have entered <x> into the calculatorAnd I have entered <y> into the calculatorWhen I press addThen the result should be <result> on the screenScenarios: addition| x | y | result|| 1 | 2 | 3 || 2 | 2 | 4 | | 3 | -3 | 0 |

15. How to Implement Step Definitions? • It’s up to you! • What you are testing? • PublicInterfaces / Components • WebUIusingbrowserautomation • WatiN, Selenium • WebUIusingRequest/Respons • Http Get/Post • Win UI usingautomation • White / Windows UI Automation

16. Resources • Specflow • http://specflow.org • Gherkin • https://github.com/aslakhellesoy/cucumber/wiki/gherkin • White • http://white.codeplex.com/ • WatiN • http://watiN.sourceforge.net