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Learn about BDD and behat

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1. Introduce TDD(Test Driven Development)

TDD is an iterative design process include the steps:

Step 1: Write a test and ensure the new test fails

Step 2: Write code to satisfy the test and ensure all tests pass

Step 3: Refactor

Step 4: Repeat

2. The problem while using and practices TDD

Programmers wanted to know:

Where to start
How much to test in one go
What to call their tests
How to understand why a test fails

These problems have been resolved in the Behavior Driven Development (BDD), So What is BDD ?

3. Introduce BDD

3.1. Definition

Behavior Driven Development (BDD)

Builds upon TDD
Write test cases in a natural language
Understood by developers and business folks alike
Helps relate domain language of requirements to the code
Do this with user stories and scenarios
User stories describe a feature's benefit in context
Scenarios are executable acceptance criteria
A story’s behavior is simply its acceptance criteria– if the system fulfills all the acceptance criteria,it’s behaving correctly; if it doesn’t, it isn’t.

3.2. Objective of BDD

Software development towards bringing the business value
Write test code first, then write programs
Make small portions
Create conditions to safely improve the code (refactor)

3.3. Benefits

Reduce time to write programs
Encourage collaboration across teams
Increased modularity, flexibility, and easy to expand

3.4. BDD had answers to some of those TDD questions

What to call their tests?

A sentence describing the next behavior in which you are interested.

When a test fails?

I had introduced a bug. Solution: Fix the bug.
The intended behaviour was still relevant but had moved elsewhere. Solution: Move the test and maybe change it.
The behaviour was no longer correct – the premise of the system had changed. Solution: Delete the test.

Where to start:

Identify the next most important thing
Identify the value of the new features
Prioritize new features
Formulate the behaviour method name

How much to test in one go:

You can only describe so much behavior in a single sentence

4. The structure of Behavior Driven Development (BDD)

BDD user stories and scenarios so A story template in BDD this look like

Title (one line describing the story)

As a [role]

I want [feature]

So that [benefit]

The structure of one scenario this look like

Scenario 1: Title

Given [context]

And [context]

When [event]

And [some more context]...

Then [outcome]

And[another outcome]...

Example: An ATM machine

5. Introduce Behat with Mink

6. Install Behat with Mink on Linux

6.1. Install LAMP

Run commands

sudo apt-get update
sudo apt-get install apache2
sudo apt-get install php5 libapache2-mod-php5 php5-mcrypt
sudo apt-get install php5-cgi php5-cli php5-common php5-curl php5-dbg php5-dev php5-gd php5-gmp php5-ldap php5-xsl

Reference https://www.digitalocean.com/community/tutorials/how-to-install-linux-apache-mysql-php-lamp-stack-on-ubuntu

6.2. Install Java

Run commands

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer

Reference http://askubuntu.com/questions/335283/how-to-reslove-unmet-dependencies-can-not-install-or-remove-packages-software

6.3. Create composer.json file in the project root

composer.json_-300x142.png

6.4. Download composer.phar and run install command

download_composer.phar_-300x35.png

6.5. Run Behat

6.6. Activate MinkExtension

6.7. Check Mink extension

7. Install and Using selenium 2

7.1. Download latest Selenium server

Download latest Selenium server file http://www.seleniumhq.org/download/

7.2. Run Selenium2 jar before test suites

7.3. Create and run scenario

8. The API of MinkContext

8.1. MinkContext Defines Steps for making requests

8.2. MinkContext Defines Steps for interacting with forms

8.3. MinkContext Defines Steps for querying the DOM

8.4. MinkContext Defines Steps for examining responses

9. A Note About Step Results

Success: a definition was found and executing it did not throw an Exception
Undefined: a definition couldn't be found; all subsequent steps will be Skipped
Pending: the definition threw the special PendingException, which means you have work to do; skip remaining steps
Failure: a definition throws an Exception; Behat will skip remaining steps and terminate with exit status 1

– By default, Behat relies on PHPUnit for assertions, but you can roll your own.

Skipped: steps which were never executed
Ambiguous: multiple definitions matched a step
Redundant: multiple definitions share the same pattern 10. Compare Behat and selenium WebDrive

10.1: Selenium webdrive

The good:

Can automate most browsers and mobile devices in many different programming languages
It’s pretty widely adopted across other frameworks as well, and can integrate with BDD tools such as Cucumber
Selenium is pretty easy to pick up with some programming knowledge
Used Selenium with Java with only minor frustration, and Selenium with Ruby and Rspec combined well with minimal set-up for an easy-to-read output and code

The bad:

Can do almost anything but doesn’t mean you should
The maintenance cost is very high and it’ll take you a while to figure out how to make each browser’s driver work with your code
You still have to manually check those browsers for visual bugs.
Difficult to find API docs

You should use this if:

QA team doesn’t have a lot of programming experience and wants to use the language they’re most comfortable with
It’s easy to get support, and you don’t have to learn a new language’s syntax
This approach is also good if you’re a developer making Selenium tests for your product - you can write in the same language your product is in without having to switch contexts as much

10.2. Behat

The good:

Can automate most browsers
Combine your acceptance criteria with your automated acceptance tests
You to think through your requirements and makes it easy for non-developers to read your code and run your tests
The syntax is easy to read for people who don’t code
Easy to find API docs

The bad: