Working with PHPUnit Testing

 

The purpose of this tutorial is to teach you how to create and run PHPUnit tests on your code. You will learn how to create and run single unit test cases and test suites containing a number of test cases.

Contents:

Purpose and Usage

 

Creating a PHPUnit Test Case

 

Running your PHPUnit Test Case

 

Analyzing Errors

 

Creating and Running a PHPUnit Test Suite

 

Generating a PHPUnit Test Report

 

Purpose and Usage

Unit testing is a procedure to test your code to ensure that individual units of source code are working properly and that the right output is being generated. Tests can be run on all or some functions within files, meaning that tests can be conducted before the file has been fully developed. Each test case should be independent of others to ensure that test results can pinpoint the location of the error.

Running unit tests can ensure that your code is stable and functioning correctly, and can help you to diagnose errors.

Creating a PHPUnit Test Case

Zend Studio will automatically create test case files which can be run in order to check the functionality of your code.

 

 

Instructions on how to complete a procedure

The following steps demonstrate how to create a PHPUnit Test Case:

  1. Create a new PHP file, called "Calculator", and copy-paste the following code into  it:

<?php

class Calculator {

public function add($a, $b) {

return $a + $b;

}

 

public function multiply($a, $b) {

return $a * $b;

}

 

public function divide($a, $b) {

if($b == null) {

throw new Exception("Division by zero");

}

return $a / $b;

}

 

public function subtract($a, $b) {

return $a - $b;

}

}

?>

  1. Save the file.

  2. In PHP Explorer view, right-click the calculator file and select New | Other | PHP | PHPUnit | PHPUnit Test Case.

The PHPUnit Test Case dialog will open.

  1. The relevant information will have already been entered. Note that a new file will be created called CalculatorTest.php
    A warning will also appear stating that the PHPUnit is not the include class of your project.

  2. To add it to the include path, click the underlined "Click here" link at the bottom of the dialog screen.
    Once it has been clicked, the link and the warning message will disappear.

  3. Click Finish to create your test case.

A CalculatorTest file will have been added to your project in PHP Explorer. This will contain tests for your original "calculator" file.
Note that all functions (add, multiply, divide and subtract) in the original "Calculator" file will have a corresponding test function in the "CalculatorTest" file:

Note:

Test functions will have been created, but parameters need to be entered in order for the test to run effectively. For more on this, see "Running your Unit Test Case", below.

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Running your PHPUnit Test Case

Having created your PHPUnit Test Case, you will now need to customize it by entering relevant parameters to be checked before being able to run your test.

 

 

Instructions on how to complete a procedure

To configure and run your test case:

  1. In the CalculatorTest file, expand public function test_add node.

  2. Note that a function has been created but no parameters have been inserted. You will have to manually enter the relevant parameters to be tested and the predicted results.

  3. Delete the following code:

// TODO Auto-generated CalculatorTest->test_add()

$this->markTestIncomplete("add test not implemented");

$this->Calculator->add(/* parameters */);

  1. This is the default test which will return a "test not implemented" result if the test case is run.

  2. Replace the above code with the following:

$this->assertEquals($this->Calculator->add(1, 2), 3);

  1. The numbers 1 and 2 indicate that when the test case is run, the parameters 1 and 2 will be entered into the 'add' function in your Calculator file (i.e. the test will try to add 1 + 2). The last number (3) indicates that the expected result is 3. If the result is something other than 3, the test will report a failure for this function.

  2. Save the file.

  3. To run the unit test, click the arrow next to the Run button on the toolbar and select Run As | PHPUnit Test –or- go to Run Menu and select Run As | PHPUnit Test .
    Or- to debug the PHPUnit Test Case, click the arrow next to the debug button on the toolbar and select Debug As | PHPUnit Test  –or- from the Main Menu, go to Run and select Debug As | PHPUnit Test .
    The unit test will be run and a PHP Unit view will open.
    As the test is run, the parameters you have configured will be entered into the relevant functions in the Calculator file to test whether the correct result is outputted according to the expected results you specified.

  4. Four tests will be displayed - one for each calculator function  - which should have passed successfully, as indicated by the green tick icon .
    Note that the other three functions (divide, multiply and subtract), will have passed but will have a note indicating that they have not been implemented. This is because you have not yet specified the testing parameters.

  5. Repeat steps 1-6 above for the remaining functions, entering suitable parameters in the format:

$this->assertEquals($this->Calculator->subtract/divide/multiply(x, y),z);

Select each required operation (subtract, divide or multiply), and enter variables where x and y are the two parameters which will be entered into the calculator, and z is the expected result.

  1. Run the Unit Test again by clicking the Run Last Test button in the PHPUnit view and check that all the test have passed successfully.

 

Notes:

  1. Tests can be written in alternate ways. So for example

$this->assertEquals($this->Calculator->add(1, 2), 3);

can also be written as:

$this->assertSame(3,$this->Calculator->add(1,2));

  1. You can create more than one test for each function, so that your function could appear as the following:

Tests Calculator->add()

 */

public function test_add()

{

$this->assertEquals($this->Calculator->add(1, 2), 3);

// $this->assertEquals($this->Calculator->add(1, 3), 4);

// $this->assertEquals($this->Calculator->add(-1, 2), 1);

}

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Analyzing Errors

Once a PHPUnit test has been run, the results can be viewed and analyzed in order to diagnose and correct problematic sections of code.

 

 

Instructions on how to complete a procedure

The following steps demonstrate how to analyze and correct errors in your code:

  1. To simulate a failed result, change the parameters under the add function so that the expected result is wrong. For example:

$this->assertEquals($this->Calculator->add(1, 2),4);

  1. Save the file.

  2. Run the Unit Test again by clicking the Run Last Test button in the PHPUnit view.

  3. The display in the PHPUnit view will now display that test_add has failed, indicated by the blue X icon .
    The error message "Failed asserting that <integer:3> is identical to <integer:4>" indicates that the test failed as the actual result of the test was 3, but the expected result was 4.

  4. To only view the failures, click the "Show failures only" button on the view's toolbar.

  5. Select a failed result to view it in the Failure Trace view. Click the Filter Stack Trace icon to filter the results and view the relevant functions.

  6. Double-click the failed result to go to the relevant section in the code.

  7. Correct the code, save the file and run the test again by clicking the Run Last Test button in the PHPUnit view.  

The tests should be successful. If they are not, repeat steps 6-8.

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Creating and Running a PHPUnit Test Suite

A number of different PHPUnit Test Cases can be unified into one UnitTest Suite file which will run all unit tests at once. This function is useful if you have a few tests within a project which you would like to run at once.

 

 

Instructions on how to complete a procedure

The following steps demonstrate how to create a PHPUnit Test Suite:

  1. Create another Unit Test Case for your "Calculator" file by following steps 3 - 7 under "Creating Unit Test Cases", above.

  2. Edit the test file to create different tests using your own tests, or copy-paste the example code into the file. (Click here to get the example code).

  1. Save the file.

  2. From PHP Explorer View, select and right-click the Calculator project.

  3. Select New | Other | PHP | PHPUnit | PHPUnit Test Suite.
    A New PHPUnit Test Suite dialog will open.

  4. Ensure that both your test cases are selected from the list.

  5. Click Finish.

  6. A new CalculatorSuite file will be created, integrating both tests into one file.

  7. Run the CalculatorSuite by clicking the arrow next to the Run button on the toolbar and select Run As | PHPUnit Test –or- go to Run Menu and select Run As | PHPUnit Test .

  8. Both tests will be run, with the results of both displayed in a tree in the PHPUnit view at the bottom of the screen.

 

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Generating PHPUnit Test Reports

 

 

Instructions on how to complete a procedure

The following steps demonstrate how to run a report on your Unit Test results:

  1. Once you have run the PHPUnit Test Suite, click the arrow next to  the Report Generator icon on the PHPUnit view's toolbar and select Transform with 'plain.xsl' from the drop-down list.
    See PHPUnit Testing for more on the different types of reports.

A report will be automatically generated and opened in a browser window.

 

 

 

Related Links

Related Links:

Using PHPUnit Testing

Creating a PHPUnit Test Case

Creating a PHPUnit Test Suite

Running a PHPUnit Test Case

Running a PHPUnit Test Suite

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