Issue #3126566 by greg.1.anderson, jungle, tedbow, hussainweb, Kristen Pol, alexpott: Allow Drupal to work with Composer 2

composer.lock

@@ -884,10 +884,10 @@
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/ProjectMessage",
-                "reference": "3b795f469441eb27854798f70cb38e717d80bbfc"
+                "reference": "ed6afc20bfed583e5325ca86f78d07a653d6045c"
             },
             "require": {
-                "composer-plugin-api": "^1.1",
+                "composer-plugin-api": "^1.1 || ^2",
                 "php": ">=7.0.8"
             },
             "type": "composer-plugin",
@@ -914,10 +914,10 @@
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/VendorHardening",
-                "reference": "2db54f089065dedbe4a040b01f7b527f2bad68f6"
+                "reference": "6773d713a655ec8a5ac8c29cd5df653cfec6d3cc"
             },
             "require": {
-                "composer-plugin-api": "^1.1",
+                "composer-plugin-api": "^1.1 || ^2",
                 "php": ">=7.0.8"
             },
             "type": "composer-plugin",

composer/Plugin/ProjectMessage/MessagePlugin.php

@@ -45,6 +45,18 @@ class MessagePlugin implements PluginInterface, EventSubscriberInterface {
     $this->io = $io;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function deactivate(Composer $composer, IOInterface $io) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function uninstall(Composer $composer, IOInterface $io) {
+  }
+
   /**
    * {@inheritdoc}
    */

composer/Plugin/ProjectMessage/composer.json

@@ -15,6 +15,6 @@
   },
   "require": {
     "php": ">=7.0.8",
-    "composer-plugin-api": "^1.1"
+    "composer-plugin-api": "^1.1 || ^2"
   }
 }

composer/Plugin/Scaffold/AllowedPackages.php

@@ -3,6 +3,7 @@
 namespace Drupal\Composer\Plugin\Scaffold;
 
 use Composer\Composer;
+use Composer\DependencyResolver\Operation\OperationInterface;
 use Composer\Installer\PackageEvent;
 use Composer\IO\IOInterface;
 use Composer\Package\PackageInterface;
@@ -96,8 +97,12 @@ class AllowedPackages implements PostPackageEventListenerInterface {
    */
   public function event(PackageEvent $event) {
     $operation = $event->getOperation();
-    // Determine the package.
-    $package = $operation->getJobType() == 'update' ? $operation->getTargetPackage() : $operation->getPackage();
+    // Determine the package. Later, in evaluateNewPackages(), we will report
+    // which of the newly-installed packages have scaffold operations, and
+    // whether or not they are allowed to scaffold by the allowed-packages
+    // option in the root-level composer.json file.
+    $operationType = $this->getOperationType($operation);
+    $package = $operationType === 'update' ? $operation->getTargetPackage() : $operation->getPackage();
     if (ScaffoldOptions::hasOptions($package->getExtra())) {
       $this->newPackages[$package->getName()] = $package;
     }
@@ -176,6 +181,26 @@ class AllowedPackages implements PostPackageEventListenerInterface {
     return $allowed_packages;
   }
 
+  /**
+   * Determine the type of the provided operation.
+   *
+   * Adjusts API used for Composer 1 or Composer 2.
+   *
+   * @param \Composer\DependencyResolver\Operation\OperationInterface $operation
+   *   The operation object.
+   *
+   * @return string
+   *   The operation type.
+   */
+  protected function getOperationType(OperationInterface $operation) {
+    // Use Composer 2 method.
+    if (method_exists($operation, 'getOperationType')) {
+      return $operation->getOperationType();
+    }
+    // Fallback to Composer 1 method.
+    return $operation->getJobType();
+  }
+
   /**
    * Retrieves a package from the current composer process.
    *

composer/Plugin/Scaffold/Plugin.php

@@ -60,6 +60,18 @@ class Plugin implements PluginInterface, EventSubscriberInterface, Capable {
     $this->requireWasCalled = FALSE;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function deactivate(Composer $composer, IOInterface $io) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function uninstall(Composer $composer, IOInterface $io) {
+  }
+
   /**
    * {@inheritdoc}
    */

composer/Plugin/Scaffold/composer.json

@@ -6,7 +6,7 @@
   "homepage": "https://www.drupal.org/project/drupal",
   "license": "GPL-2.0-or-later",
   "require": {
-    "composer-plugin-api": "^1.0.0",
+    "composer-plugin-api": "^1 || ^2",
     "php": ">=7.0.8"
   },
   "conflict": {

composer/Plugin/VendorHardening/VendorHardeningPlugin.php

@@ -65,6 +65,18 @@ class VendorHardeningPlugin implements PluginInterface, EventSubscriberInterface
     $this->config = new Config($this->composer->getPackage());
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function deactivate(Composer $composer, IOInterface $io) {
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function uninstall(Composer $composer, IOInterface $io) {
+  }
+
   /**
    * {@inheritdoc}
    */

composer/Plugin/VendorHardening/composer.json

@@ -15,6 +15,6 @@
   },
   "require": {
     "php": ">=7.0.8",
-    "composer-plugin-api": "^1.1"
+    "composer-plugin-api": "^1.1 || ^2"
   }
 }

core/tests/Drupal/BuildTests/Composer/Template/ComposerProjectTemplatesTest.php

@@ -104,6 +104,11 @@ class ComposerProjectTemplatesTest extends BuildTestBase {
    * @dataProvider provideTemplateCreateProject
    */
   public function testTemplateCreateProject($project, $package_dir, $docroot_dir) {
+    $composerVersionLine = exec('composer --version');
+    if (strpos($composerVersionLine, 'Composer version 2') !== FALSE) {
+      $this->markTestSkipped('We cannot run the template create project test with Composer 2 until we have a stable version of composer/semver 2.x. The create project test installs drupal/core-recommended and the Drupal Composer plugins from Packagist, so these must also be compatible with Composer 2.x in order for this test to work.');
+    }
+
     $this->copyCodebase();
 
     // Get the Drupal core version branch. For instance, this should be

core/tests/Drupal/Tests/Composer/Plugin/Scaffold/Functional/ScaffoldUpgradeTest.php

@@ -44,6 +44,10 @@ class ScaffoldUpgradeTest extends TestCase {
    * Test upgrading the Composer Scaffold plugin.
    */
   public function testScaffoldUpgrade() {
+    $composerVersionLine = exec('composer --version');
+    if (strpos($composerVersionLine, 'Composer version 2') !== FALSE) {
+      $this->markTestSkipped('We cannot run the scaffold upgrade test with Composer 2 until we have a stable version of drupal/core-composer-scaffold to start from that we can install with Composer 2.x.');
+    }
     $this->fixturesDir = $this->fixtures->tmpDir($this->getName());
     $replacements = ['SYMLINK' => 'false', 'PROJECT_ROOT' => $this->fixtures->projectRoot()];
     $this->fixtures->cloneFixtureProjects($this->fixturesDir, $replacements);