Issue #3126566 by greg.1.anderson, jungle, tedbow, hussainweb, Kriste…

…n Pol, alexpott: Allow Drupal to work with Composer 2

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

@@ -104,6 +104,11 @@ public function testVerifyTemplateTestProviderIsAccurate() {
    * @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

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

@@ -44,6 +44,10 @@ protected function setUp() {
    * 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);