Unit Testing PHP codeSudar Muthu

http://sudarmuthu.com https://github.com/sudar

Me

• Programming in PHP for more than a decade

• Programming in WordPress for 8 years

• Big fan of automating process and workflows

• Occasionally contribute to open source projects

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What about you?

• What is your typical development environment looks like?

• What is your experience with PHP?

• What is your experience with Unit Testing?

• What are your expectations out of this talk?

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Is there something wrong?class Sample { protected $value;

public function initialize($value) { $this->value = $value; }

public function execute() { if (!$this->value) { throw new Exception("value not set"); } return $value * 10; // business logic }}

$sample = new Sample;$sample->execute();

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Finding bugs is not easy

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Write Tests

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Write Tests

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It sounds obvious but getting started is the hardest part!

Different types of Testing

• Functionality testing

• Integration testing

• Unit testing

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Different types of Testing

• Functionality testing

• Integration testing

• Unit testing

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Briefly

• What is PHPUnit?

• Installing PHPUnit

• Setting up folder structure

• phpunit.xml

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Test classes, not methods

• Unit testing, is about testing the observable behaviours of a class!

• Observable from the outside! Nobody cares about the internal state of a class if it never changes the outcome of a method call.

• Don’t test getters and setters, unless they have custom validation

Three steps in test cases

• setup

• act

• verify

Demo

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Writing our first test case public function test_execute_works_with_initialize() { // setup $sample = new Sample();

// act $sample->initialize(10); $return = $sample->execute();

// verify $this->assertEquals(100, $return); }

Testing Exception /** * @expectedException Exception */ public function test_execute_needs_initialize() { // setup $sample = new Sample();

// act $sample->execute();

// verify // that it throws and exception }

Let’s add more tests

• Testing decimals

• Testing with negative values

• Testing it work with zero

Why use mocks?

• Isolate the test class from its dependencies.

• Test functionality that calls external services.

• Test functionality that depends on class internals.

Some PHPUnit Tips• Have a fast test suite

• Use Continuous Integration

• Use Composer

• Enable code coverage in reports

• phpunit.xml.dist vs phpunit.xml

• Use specific assertions

Thank You

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@sudarmuthu http://sudarmuthu.com

https://github.com/sudar