Autoloading classes in PHPUnit using Composer and autoload.php

Well, at first. You need to tell the autoloader where to find the php file for a class. That's done by following the PSR-0 standard.

The best way is to use namespaces. The autoloader searches for a Acme/Tests/ReturningTest.php file when you requested a Acme\Tests\ReturningTest class. There are some great namespace tutorials out there, just search and read. Please note that namespacing is not something that came into PHP for autoloading, it's something that can be used for autoloading.

Composer comes with a standard PSR-0 autoloader (the one in vendor/autoload.php). In your case you want to tell the autoloader to search for files in the lib directory. Then when you use ReturningTest it will look for /lib/ReturningTest.php.

Add this to your composer.json:

{
    ...
    "autoload": {
        "psr-0": { "": "lib/" }
    }
}

More information in the documentation.

Now the autoloader can find your classes you need to let PHPunit know there is a file to execute before running the tests: a bootstrap file. You can use the --bootstrap option to specify where the bootstrap file is located:

$ ./vendor/bin/phpunit tests --bootstrap vendor/autoload.php

However, it's nicer to use a PHPunit configuration file:

<!-- /phpunit.xml.dist -->
<?xml version="1.0" encoding="utf-8" ?>
<phpunit bootstrap="./vendor/autoload.php">

    <testsuites>
        <testsuite name="The project's test suite">
            <directory>./tests</directory>
        </testsuite>
    </testsuites>

</phpunit>

Now, you can run the command and it will automatically detect the configuration file:

$ ./vendor/bin/phpunit

If you put the configuration file into another directory, you need to put the path to that directory in the command with the -c option.

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[Update2] Another simpler alternative approach is to use the autoload-dev directive in composer.json (reference). The benefit is that you don't need to maintain two bootstrap.php (one for prod, one for dev) just in order to autoload different classes.

{
  "autoload": {
    "psr-4": { "MyLibrary\\": "src/" }
  },
  "autoload-dev": {
    "psr-4": { "MyLibrary\\Tests\\": "tests/" }
  }
}

[Update] Wouter J's answer is more complete. But mine can help people who want to set up PSR-0 autoloading in tests/ folder.
Phpunit scans all files with this pattern *Test.php. So we don't need to autoload them ourselves. But we still want to autoload other supporting classes under tests/ such as fixture/stub or some parent classes.

An easy way is to look at how Composer project itself is setting up the phpunit test. It's actually very simple. Note the line with "bootstrap".

reference: https://github.com/composer/composer/blob/master/phpunit.xml.dist

<?xml version="1.0" encoding="UTF-8"?>

<phpunit backupGlobals="false"
         backupStaticAttributes="false"
         colors="true"
         convertErrorsToExceptions="true"
         convertNoticesToExceptions="true"
         convertWarningsToExceptions="true"
         processIsolation="false"
         stopOnFailure="false"
         syntaxCheck="false"
         bootstrap="tests/bootstrap.php"
>
    <testsuites>
        <testsuite name="Composer Test Suite">
            <directory>./tests/Composer/</directory>
        </testsuite>
    </testsuites>

    <groups>
        <exclude>
            <group>slow</group>
        </exclude>
    </groups>

    <filter>
        <whitelist>
            <directory>./src/Composer/</directory>
            <exclude>
                <file>./src/Composer/Autoload/ClassLoader.php</file>
            </exclude>
        </whitelist>
    </filter>
</phpunit>

reference: https://github.com/composer/composer/blob/master/tests/bootstrap.php

<?php

/*
* This file is part of Composer.
*
* (c) Nils Adermann <naderman@naderman.de>
* Jordi Boggiano <j.boggiano@seld.be>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/

error_reporting(E_ALL);

$loader = require __DIR__.'/../src/bootstrap.php';
$loader->add('Composer\Test', __DIR__);

The last line above is autoloading phpunit test classes under the namespace Composer\Test.

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None of these answers were what I was looking for. Yes PHPUnit loads test files, but not stubs/fixtures. Chaun Ma's answer doesn't cut it because running vendor/bin/phpunit already includes the autoload, so there's no way to get an instance of the autoloader to push more paths to it's stack at that point.

I eventually found this in the docs:

If you need to search for a same prefix in multiple directories, you can specify them as an array as such: { "autoload": { "psr-0": { "Monolog\\": ["src/", "lib/"] } } }

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There is a really simple way to set up phpunit with autoloading and bootstap. Use phpunit's --generate-configuration option to create your phpunit.xml configuration in a few seconds-:

vendor/bin/phpunit --generate-configuration

(Or just phpunit --generate-configuration if phpunit is set in your PATH). This option has been available from version phpunit5 and upwards.

This option will prompt you for your bootstrap file (vendor/autoload.php), tests and source directories. If your project is setup with composer defaults (see below directory structure) the default options will be all you need. Just hit RETURN three times!

project-dir
   -- src
   -- tests
   -- vendor

You get a default phpunit.xml which is good to go. You can of course edit to include any specialisms (e.g. colors="true") you require-:

<?xml version="1.0" encoding="UTF-8"?>
<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/8.1/phpunit.xsd"
         bootstrap="vendor/autoload.php"
         executionOrder="depends,defects"
         forceCoversAnnotation="true"
         beStrictAboutCoversAnnotation="true"
         beStrictAboutOutputDuringTests="true"
         beStrictAboutTodoAnnotatedTests="true"
         verbose="true">
    <testsuites>
        <testsuite name="default">
            <directory suffix="Test.php">tests</directory>
        </testsuite>
    </testsuites>
    <filter>
        <whitelist processUncoveredFilesFromWhitelist="true">
            <directory suffix=".php">src</directory>
        </whitelist>
    </filter>
</phpunit>

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If you are using PHPUnit 7 you can make your classes from src/ folder to autoload in tests like this:

Ensure that your composer.json file looks similar to this: { "autoload": { "classmap": [ "src/" ] }, "require-dev": { "phpunit/phpunit": "^7" } } To apply changes in composer.json run command: composer install Finally you can run tests in tests/ folder: ./vendor/bin/phpunit tests/

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