test: add AdminPageTest

Test that anonymous users cannot access the administration area and
users with the 'access administration pages' can.

web/modules/custom/example/tests/src/Functional/AdminPageTest.php

@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\Tests\example\Functional;
+
+use Drupal\Tests\BrowserTestBase;
+use Symfony\Component\HttpFoundation\Response;
+
+final class AdminPageTest extends BrowserTestBase {
+
+  public $defaultTheme = 'stark';
+
+  /** @test */
+  public function the_admin_page_is_not_accessible_to_anonymous_users(): void {
+    $this->drupalGet(path: '/admin');
+
+    $assert = $this->assertSession();
+
+    $assert->statusCodeEquals(Response::HTTP_FORBIDDEN);
+  }
+
+  /** @test */
+  public function the_admin_page_is_accessible_by_admin_users(): void {
+    $adminUser = $this->createUser(
+      permissions: [
+        'access administration pages',
+      ],
+    );
+
+    $this->drupalLogin(account: $adminUser);
+
+    $this->drupalGet(path: '/admin');
+
+    $assert = $this->assertSession();
+
+    $assert->statusCodeEquals(Response::HTTP_OK);
+  }
+
+}

web/modules/custom/example/tests/src/Functional/ExamplePageTest.php

@@ -1,31 +0,0 @@
-<?php
-
-namespace Drupal\Tests\example\Functional;
-
-use Drupal\Tests\BrowserTestBase;
-use Symfony\Component\HttpFoundation\Response;
-
-final class ExamplePageTest extends BrowserTestBase {
-
-  public $defaultTheme = 'stark';
-
-  protected static $modules = [
-    // Core.
-    'node',
-
-    // Custom.
-    "example"
-  ];
-
-  /** @test */
-  public function should_load_the_example_page_for_anonymous_users(): void {
-    // Arrange.
-
-    // Act.
-    $this->drupalGet('/@opdavies/drupal-module-template');
-
-    // Assert.
-    $this->assertSession()->statusCodeEquals(Response::HTTP_OK);
-  }
-
-}