diff --git a/automatic_updates_extensions/tests/fixtures/active_composer/no_project/composer.json b/automatic_updates_extensions/tests/fixtures/no_project/composer.json
similarity index 100%
rename from automatic_updates_extensions/tests/fixtures/active_composer/no_project/composer.json
rename to automatic_updates_extensions/tests/fixtures/no_project/composer.json
diff --git a/automatic_updates_extensions/tests/fixtures/no_project/composer.lock b/automatic_updates_extensions/tests/fixtures/no_project/composer.lock
new file mode 100644
index 0000000000000000000000000000000000000000..a453560509d23ab0b995b6e732cc92a1864f212f
--- /dev/null
+++ b/automatic_updates_extensions/tests/fixtures/no_project/composer.lock
@@ -0,0 +1,11 @@
+{
+    "packages": [
+        {
+            "name": "drupal/core-recommended",
+            "version": "9.8.0",
+            "require": {
+                "drupal/core": "9.8.0"
+            }
+        }
+    ]
+}
diff --git a/automatic_updates_extensions/tests/fixtures/active_composer/no_project/vendor/composer/installed.json b/automatic_updates_extensions/tests/fixtures/no_project/vendor/composer/installed.json
similarity index 100%
rename from automatic_updates_extensions/tests/fixtures/active_composer/no_project/vendor/composer/installed.json
rename to automatic_updates_extensions/tests/fixtures/no_project/vendor/composer/installed.json
diff --git a/automatic_updates_extensions/tests/fixtures/active_composer/one_project/composer.json b/automatic_updates_extensions/tests/fixtures/one_project/composer.json
similarity index 100%
rename from automatic_updates_extensions/tests/fixtures/active_composer/one_project/composer.json
rename to automatic_updates_extensions/tests/fixtures/one_project/composer.json
diff --git a/automatic_updates_extensions/tests/fixtures/one_project/composer.lock b/automatic_updates_extensions/tests/fixtures/one_project/composer.lock
new file mode 100644
index 0000000000000000000000000000000000000000..eb940f5c3512154711ae9107114a8e5be800ef68
--- /dev/null
+++ b/automatic_updates_extensions/tests/fixtures/one_project/composer.lock
@@ -0,0 +1,15 @@
+{
+    "packages": [
+        {
+            "name": "drupal/core-recommended",
+            "version": "9.8.0",
+            "require": {
+                "drupal/core": "9.8.0"
+            }
+        },
+        {
+            "name": "drupal/semver_test",
+            "version": "9.8.1"
+        }
+    ]
+}
diff --git a/automatic_updates_extensions/tests/fixtures/active_composer/one_project/vendor/composer/installed.json b/automatic_updates_extensions/tests/fixtures/one_project/vendor/composer/installed.json
similarity index 100%
rename from automatic_updates_extensions/tests/fixtures/active_composer/one_project/vendor/composer/installed.json
rename to automatic_updates_extensions/tests/fixtures/one_project/vendor/composer/installed.json
diff --git a/automatic_updates_extensions/tests/fixtures/active_composer/two_projects/composer.json b/automatic_updates_extensions/tests/fixtures/two_projects/composer.json
similarity index 100%
rename from automatic_updates_extensions/tests/fixtures/active_composer/two_projects/composer.json
rename to automatic_updates_extensions/tests/fixtures/two_projects/composer.json
diff --git a/automatic_updates_extensions/tests/fixtures/two_projects/composer.lock b/automatic_updates_extensions/tests/fixtures/two_projects/composer.lock
new file mode 100644
index 0000000000000000000000000000000000000000..51df43c0cc65a352cb90e664333227a0065acac0
--- /dev/null
+++ b/automatic_updates_extensions/tests/fixtures/two_projects/composer.lock
@@ -0,0 +1,19 @@
+{
+    "packages": [
+        {
+            "name": "drupal/core-recommended",
+            "version": "9.8.0",
+            "require": {
+                "drupal/core": "9.8.0"
+            }
+        },
+        {
+            "name": "drupal/semver_test",
+            "version": "9.8.1"
+        },
+        {
+            "name": "drupal/aaa_update_test",
+            "version": "9.8.1"
+        }
+    ]
+}
diff --git a/automatic_updates_extensions/tests/fixtures/active_composer/two_projects/vendor/composer/installed.json b/automatic_updates_extensions/tests/fixtures/two_projects/vendor/composer/installed.json
similarity index 100%
rename from automatic_updates_extensions/tests/fixtures/active_composer/two_projects/vendor/composer/installed.json
rename to automatic_updates_extensions/tests/fixtures/two_projects/vendor/composer/installed.json
diff --git a/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/automatic_updates_extensions_test.info.yml b/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/automatic_updates_extensions_test.info.yml
deleted file mode 100644
index 911c33c6ca3aecf21c70acb75145f5cfed8f4dee..0000000000000000000000000000000000000000
--- a/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/automatic_updates_extensions_test.info.yml
+++ /dev/null
@@ -1,6 +0,0 @@
-name: 'Automatic Updates Extensions Test'
-description: 'Automatic Updates Extensions Test module'
-type: module
-package: Testing
-dependencies:
-  - automatic_updates:automatic_updates_extensions
diff --git a/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/src/AutomaticUpdatesExtensionsTestServiceProvider.php b/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/src/AutomaticUpdatesExtensionsTestServiceProvider.php
deleted file mode 100644
index e5797a5b2e941828425ec311b54970be5b86d3b0..0000000000000000000000000000000000000000
--- a/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/src/AutomaticUpdatesExtensionsTestServiceProvider.php
+++ /dev/null
@@ -1,24 +0,0 @@
-<?php
-
-namespace Drupal\automatic_updates_extensions_test;
-
-use Drupal\Core\DependencyInjection\ContainerBuilder;
-use Drupal\Core\DependencyInjection\ServiceModifierInterface;
-
-/**
- * Service provider to use test updater service.
- */
-class AutomaticUpdatesExtensionsTestServiceProvider implements ServiceModifierInterface {
-
-  /**
-   * {@inheritdoc}
-   */
-  public function alter(ContainerBuilder $container) {
-    if ($container->hasDefinition('automatic_updates_extensions.updater')) {
-      $container->getDefinition('automatic_updates_extensions.updater')
-        ->setClass(TestExtensionUpdater::class);
-
-    }
-  }
-
-}
diff --git a/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/src/TestExtensionUpdater.php b/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/src/TestExtensionUpdater.php
deleted file mode 100644
index 8746ae800b77cf35fd3856fbd811ae44b1ddd148..0000000000000000000000000000000000000000
--- a/automatic_updates_extensions/tests/modules/automatic_updates_extensions_test/src/TestExtensionUpdater.php
+++ /dev/null
@@ -1,23 +0,0 @@
-<?php
-
-namespace Drupal\automatic_updates_extensions_test;
-
-use Drupal\automatic_updates_extensions\ExtensionUpdater;
-use Drupal\package_manager\ComposerUtility;
-
-/**
- * Extends the updater to point to a fixture directory for the active Composer.
- */
-class TestExtensionUpdater extends ExtensionUpdater {
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getActiveComposer(): ComposerUtility {
-    if ($path = \Drupal::state()->get('automatic_updates_extensions_test.active_path')) {
-      return ComposerUtility::createForDirectory($path);
-    }
-    return parent::getActiveComposer();
-  }
-
-}
diff --git a/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php b/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php
index 5e47f55a6cb03fecedacc3adec8c79c2e6c6415e..a621711ae6463cdd613ae362d838982b458fdf00 100644
--- a/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php
+++ b/automatic_updates_extensions/tests/src/Functional/UpdaterFormTest.php
@@ -35,7 +35,6 @@ class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
   protected static $modules = [
     'automatic_updates_test',
     'automatic_updates_extensions',
-    'automatic_updates_extensions_test',
     'block',
     'semver_test',
     'aaa_update_test',
@@ -78,7 +77,10 @@ class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
     ]);
     // We need this fixture as only projects installed via composer will show up
     // on the form.
-    $this->container->get('state')->set('automatic_updates_extensions_test.active_path', __DIR__ . '/../../fixtures/active_composer/two_projects');
+    $fixture_dir = __DIR__ . '/../../fixtures/two_projects';
+    Beginner::setFixturePath($fixture_dir);
+    $this->container->get('package_manager.path_locator')
+      ->setPaths($fixture_dir, $fixture_dir . '/vendor', '');
     $this->drupalLogin($user);
     $this->drupalPlaceBlock('local_tasks_block', ['primary' => TRUE]);
   }
@@ -163,8 +165,6 @@ class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
     $this->checkForUpdates();
     $state = $this->container->get('state');
     $state->set('system.maintenance_mode', $maintenance_mode_on);
-
-    Beginner::setFixturePath(__DIR__ . '/../../fixtures/fake-site');
     StagedDatabaseUpdateValidator::setExtensionsWithUpdates(['system', 'automatic_updates_theme_with_updates']);
 
     $page = $this->getSession()->getPage();
@@ -216,13 +216,16 @@ class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
       ->save();
     $this->setProjectInstalledVersion(
       [
-        'aaa_update_test' => '8.x-2.x',
+        'aaa_update_test' => '8.x-2.0',
         'semver_test' => '8.1.0',
       ]
     );
 
     // One module not installed through composer.
-    $this->container->get('state')->set('automatic_updates_extensions_test.active_path', __DIR__ . '/../../fixtures/active_composer/one_project');
+    $fixture_dir = __DIR__ . '/../../fixtures/one_project';
+    Beginner::setFixturePath($fixture_dir);
+    $this->container->get('package_manager.path_locator')
+      ->setPaths($fixture_dir, $fixture_dir . '/vendor', '');
     $assert = $this->assertSession();
     $user = $this->createUser(
       [
@@ -237,7 +240,10 @@ class UpdaterFormTest extends AutomaticUpdatesFunctionalTestBase {
     $this->assertTableShowsUpdates('Semver Test', '8.1.0', '8.1.1');
 
     // Both of the modules not installed through composer.
-    $this->container->get('state')->set('automatic_updates_extensions_test.active_path', __DIR__ . '/../../fixtures/active_composer/no_project');
+    $fixture_dir = __DIR__ . '/../../fixtures/no_project';
+    Beginner::setFixturePath($fixture_dir);
+    $this->container->get('package_manager.path_locator')
+      ->setPaths($fixture_dir, $fixture_dir . '/vendor', '');
     $this->getSession()->reload();
     $assert->pageTextContains('Updates were found, but they must be performed manually. See the list of available updates for more information.');
     $this->assertNoUpdates();