Issue #3343463 by yash.rode: When finding an installed package by Drupal...

Issue #3343463 by yash.rode: When finding an installed package by Drupal project name, throw an exception if we find the same project name across multiple packages

package_manager/src/InstalledPackage.php

@@ -61,6 +61,9 @@ final class InstalledPackage {
    *     `drupal-profile`.
    *   - The package's vendor is not `drupal`.
    *   - The project name could not otherwise be determined.
+   *
+   * @throws \UnexpectedValueException
+   *   Thrown if the same project name exists in more than one package.
    */
   public function getProjectName(): ?string {
     // Only consider packages which are packaged by drupal.org and will be

package_manager/src/InstalledPackagesList.php

@@ -118,14 +118,16 @@ final class InstalledPackagesList extends \ArrayObject {
    *   be determined.
    */
   public function getPackageByDrupalProjectName(string $project_name): ?InstalledPackage {
+    $matching_package = NULL;
     foreach ($this as $package) {
       if ($package->getProjectName() === $project_name) {
-        // @todo Throw an exception if we find more than one package matching
-        //   $project_name in https://drupal.org/i/3343463.
-        return $package;
+        if ($matching_package) {
+          throw new \UnexpectedValueException(sprintf("Project '%s' was found in packages '%s' and '%s'.", $project_name, $matching_package->name, $package->name));
+        }
+        $matching_package = $package;
       }
     }
-    return NULL;
+    return $matching_package;
   }
 
   /**

package_manager/tests/src/Kernel/InstalledPackagesListTest.php

@@ -120,6 +120,29 @@ class InstalledPackagesListTest extends PackageManagerKernelTestBase {
     ]);
     $this->assertNull($list->getPackageByDrupalProjectName('custom_module'));
     $this->assertNull($list->getPackageByDrupalProjectName('custom_theme'));
+
+    // The project name is repeated.
+    (new ActiveFixtureManipulator())
+      ->addProjectAtPath('projects/duplicate_project')
+      ->addProjectAtPath('projects/repeat/duplicate_project')
+      ->commitChanges();
+    $list = new InstalledPackagesList([
+      'drupal/test_project1' => InstalledPackage::createFromArray([
+        'name' => 'drupal/test_project1',
+        'version' => '1.0.0',
+        'type' => 'drupal-module',
+        'path' => $projects_path . '/duplicate_project',
+      ]),
+      'drupal/test_project2' => InstalledPackage::createFromArray([
+        'name' => 'drupal/test_project2',
+        'version' => '1.0.0',
+        'type' => 'drupal-module',
+        'path' => $projects_path . '/repeat/duplicate_project',
+      ]),
+    ]);
+    $this->expectException(\UnexpectedValueException::class);
+    $this->expectExceptionMessage("Project 'duplicate_project' was found in packages 'drupal/test_project1' and 'drupal/test_project2'.");
+    $list->getPackageByDrupalProjectName('duplicate_project');
   }
 
 }