Why use PHPUnit?

Testing is an essential aspect of developing in any programming language. Manual testing can only be performed irregularly and usually only in limited ways. The answer to testing source code regularly, and in-depth, is to write automated tests that can be frequently executed.

PHPUnit is basically used for testing purposes. This is a testing framework of the PHP programming language. PHPUnit is widely used in various software testing companies. PHPUnit is mainly used for unit testing. When a developer develops any web application, there might be chances of bugs coming into the picture during the course of development. It is really hard to resolve one bug after another. PHPUnit helps to reduce such types of bugs. In this, we write unit test cases against each and every method we write in development. Also, there are some assertions like assertEquals in PHPUnit which can be used to validate things.

Below is an example to write a unit test:

Suppose there is a method called sum for which we have to write a unit test case:

Function sum ($a, $b)


$c = $a + $b;

  return  $c;


Unit test for the above method is below:

Function test_sum()


$expected_result = 9;

$actual_result = sum(4,5);  // Here we are calling the method for which we are writing the unit test

$this->assertEquals($expected_result, $actual_result); // Assertion for verifying if method is working fine or not



In this article, we have learned why do we use PHPUnit. Also, You can see in a simple example, PHPUnit saves a lot of development time for developers because by writing unit tests, our code becomes less prone to defects. Other than unit testing, PHPUnit is also used with Selenium to test the Web UI of any web application.