Issue #3249553 by omkar.podey, tim.plunkett, tedbow, phenaproxima,...

      - '@string_translation'

    tags:

      - { name: 'event_subscriber' }

  project_browser.composer_validator.package_not_installed_validator:

    class: Drupal\project_browser\ComposerInstaller\Validator\PackageNotInstalledValidator

    arguments:

      - '@string_translation'

    tags:

      - { name: 'event_subscriber' }

  cache.project_browser:

    class: Drupal\Core\Cache\CacheBackendInterface

    tags:

<?php

namespace Drupal\project_browser\ComposerInstaller\Validator;

use Drupal\Core\StringTranslation\StringTranslationTrait;

use Drupal\Core\StringTranslation\TranslationInterface;

use Drupal\package_manager\Event\PreRequireEvent;

use Drupal\project_browser\ComposerInstaller\Installer;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**

 * Validates that packages to be installed are not already installed.

 *

 * @internal

 *   Tagged services are internal.

 */

final class PackageNotInstalledValidator implements EventSubscriberInterface {

  use StringTranslationTrait;

  /**

   * Constructs a PackageNotInstalledValidator object.

   *

   * @param \Drupal\Core\StringTranslation\TranslationInterface $translation

   *   The translation service.

   */

  public function __construct(TranslationInterface $translation) {

    $this->setStringTranslation($translation);

  }

  /**

   * Validates that packages are not already installed with composer.

   *

   * @param \Drupal\package_manager\Event\PreRequireEvent $event

   *   The event object.

   */

  public function validatePackagesNotAlreadyInstalled(PreRequireEvent $event): void {

    $stage = $event->getStage();

    if (!$stage instanceof Installer) {

      return;

    }

    $installed_packages = $stage->getActiveComposer()->getInstalledPackages();

    // Assuming project browser cannot install dev releases, since we are not

    // calling $event->getDevPackages() for now.

    $required_packages = $event->getRuntimePackages();

    $already_installed_packages = [];

    foreach (array_keys($required_packages) as $required_package) {

      if (array_key_exists($required_package, $installed_packages)) {

        $already_installed_packages[] = $required_package;

      }

    }

    if (!empty($already_installed_packages)) {

      $summary = $this->formatPlural(count($already_installed_packages), 'The following package is already installed:', 'The following packages are already installed:');

      $event->addError($already_installed_packages, $summary);

    }

  }

  /**

   * {@inheritdoc}

   */

  public static function getSubscribedEvents() {

    return [

      PreRequireEvent::class => 'validatePackagesNotAlreadyInstalled',

    ];

  }

}

{

    "packages": [

        {

            "name": "drupal/core-recommended",

            "version": "9.8.0",

            "require": {

                "drupal/core": "9.8.0"

            }

        },

        {

            "name": "drupal/core",

            "version": "9.8.0"

        },

        {

            "name": "drupal/my_module",

            "version": "9.8.0",

            "type": "drupal-module"

        },

        {

            "name": "drupal/my_module_2",

            "version": "9.8.0",

            "type": "drupal-module"

        },

        {

            "name": "drupal/my_dev_module",

            "version": "9.8.1",

            "type": "drupal-module"

        }

    ],

    "dev": true,

    "dev-package-names": [

        "drupal/my_dev_module"

    ]

}

<?php

namespace Drupal\Tests\project_browser\Kernel\Validator;

use Drupal\package_manager\ValidationResult;

use Drupal\project_browser\Exception\InstallException;

use Drupal\Tests\package_manager\Kernel\PackageManagerKernelTestBase;

/**

 * @covers \Drupal\project_browser\ComposerInstaller\Validator\PackageNotInstalledValidator

 *

 * @group project_browser

 */

class PackageNotInstalledValidatorTest extends PackageManagerKernelTestBase {

  /**

   * {@inheritdoc}

   */

  protected static $modules = [

    'project_browser',

  ];

  /**

   * {@inheritdoc}

   */

  protected function setUp(): void {

    parent::setUp();

    $active_dir = $this->container->get('package_manager.path_locator')

      ->getProjectRoot();

    $installed = __DIR__ . '/../../../fixtures/ComposerInstaller/PackageNotInstalledValidator/active.installed.json';

    $this->assertFileIsReadable($installed);

    copy($installed, $active_dir . '/vendor/composer/installed.json');

  }

  /**

   * Data provider for testPreRequireException().

   *

   * @return array[]

   *   The test cases.

   */

  public function providerPreRequireException(): array {

    $summary = t('The following package is already installed:');

    $summary_plural = t('The following packages are already installed:');

    return [

      'new package which is currently *not* installed' => [

        ['drupal/new_module'],

        NULL,

      ],

      'already installed package' => [

        ['drupal/my_module'],

        ValidationResult::createError(['drupal/my_module'], $summary),

      ],

      '2 packages sent, 1 is already installed' => [

        ['drupal/new_module', 'drupal/my_module'],

        ValidationResult::createError(['drupal/my_module'], $summary),

      ],

      '2 packages sent, both already installed' => [

        ['drupal/my_module', 'drupal/my_module_2'],

        ValidationResult::createError(['drupal/my_module', 'drupal/my_module_2'], $summary_plural),

      ],

    ];

  }

  /**

   * Tests the packages installed with Composer during pre-create.

   *

   * @param string[] $packages

   *   The packages to install.

   * @param \Drupal\package_manager\ValidationResult|null $expected_result

   *   The expected validation result if any, otherwise NULL.

   *

   * @dataProvider providerPreRequireException

   */

  public function testPreRequireException(array $packages, ?ValidationResult $expected_result): void {

    try {

      /** @var \Drupal\project_browser\ComposerInstaller\Installer $installer */

      $installer = $this->container->get('project_browser.installer');

      $installer->create();

      $installer->require($packages);

      // If we did not get an exception, ensure we didn't expect any results.

      $this->assertNull($expected_result);

    }

    catch (InstallException $e) {

      $this->assertNotNull($expected_result);

      $this->assertValidationResultsEqual([$expected_result], $e->getResults());

    }

  }

}