Perl Behavior Driven Development (BDD)

Perl Behavior Driven Development (BDD)

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  Behavior Driven Development in Perl TudorConstantin - perl hacker @ Evozon
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  Contents ● Objectives ● TDD and its disadvantages ● How BDD works ● BDD and The Mojolicious-Boilerplate ● Wishlist ● Conclusions ● References
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  Objectives Assuming you havethe following user story to implement: Feature: Standard Signup In order to begin using the application As a new user I want to create an account Scenario: Signup with valid email/password combination Given I do not have an account When I signup with email and password Then I should be logged in And my profile details should be filled in
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  Objectives Following TDD, you'dhave to start writing tests that will guarantee your app functionality
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  Objectives Objective achieved With BDD,that user story IS your test suite for that scenario Perl BDD Module: ● Peter Sergeant's Test::BDD::Cucumber
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  Objectives Feature: Standard Signup In order to begin using the application As a new user I want to create an account Scenario: Signup with valid email/password combination Given I do not have an account When I signup with email and password Then I should be logged in And my profile details should be filled in Legend: (this text is parsed by the BDD framework) (your actual test knows what to do with this text)
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  TDD and itsdisadvantages ● Where to start ● What to test and what not to test ● How much to test in one go ● What name should that test have ● How to organize the tests in files ● How to setup and share context between tests
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  How BDD Works 1.Stakeholders write a formal user story a. Feature section - free form text describing that particular feature of the application b. Background section - parsable text meant to set up the context for testing that feature - ex: "Given I am logged in as administrator" i. each Feature might have a Background section c. Scenario(s) section(s) i. each feature has one or more scenarios d. Steps i. each scenario has one or more steps
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  How BDD Works 2.The developer implements each step Example of Implementation for the step 'Givena mojo test object for the "Boilerplate" application'
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  How BDD Works Givenqr/a mojo test object for the "(.+)" application/, func ($c) { use_ok( $1 ); my $tm = Test::Mojo->new( $1 ); ok( $tm, "Object created" ); $c->stash->{'feature'}->{'tm'} = $tm; ok( $c->stash->{'feature'}->{'tm'}, "Got our Test::Mojo object" ); };
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  BDD and TheMojolicious-Boilerplate ● Started using BDD as the way to test apps using the Mojolicious-Boilerplate ● There are passing scenarios ● There are failing scenarios ● Get involved and take on the opportunity to learn BDD in practice
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  BDD and TheMojolicious-Boilerplate Scenario file: Mojolicious-Boilerplate / t / features / mojo.feature
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  BDD and TheMojolicious-Boilerplate Steps File: Mojolicious-Boilerplate / t / features / step_definitions / mojo_steps.pl
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  Wishlist Road Map ●Create more scenarios/user-stories ● Find a way to get a more convenient map between Mojolicious Routes, URL display text and URL value ● Create a Bootstrap-specific grammar ○ will make the testing process even less "programmer bound" ○ most HTML elements are contained in tags with Bootstrap specific css classes ● More, better documentation
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  Conclusions ● easy wayto get started in writing tests ● test-scenarios and tests are self documented ● natural way of logically split the test files into functionality related files/folders/objects
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  References ● http://en.wikipedia.org/wiki/Behavior_Driven_Development ● Peter Sergeant's Test::BDD::Cucumber::Manual::Tutorial ● Mojolicious Boilerplate ● Story Driven Development With Cucumber