diff --git a/tests/ThemeTest.php b/tests/ThemeTest.php
index 51fdfe70d..8faf7711e 100644
--- a/tests/ThemeTest.php
+++ b/tests/ThemeTest.php
@@ -1,43 +1,74 @@
 <?php namespace Tests;
 
+use BookStack\Entities\Models\Page;
+use BookStack\Entities\Tools\PageContent;
+use BookStack\Facades\Theme;
+use BookStack\Theming\ThemeEvents;
 use File;
+use League\CommonMark\ConfigurableEnvironmentInterface;
 
 class ThemeTest extends TestCase
 {
     protected $themeFolderName;
     protected $themeFolderPath;
 
-    public function setUp(): void
+    public function test_translation_text_can_be_overridden_via_theme()
     {
-        parent::setUp();
+        $this->usingThemeFolder(function() {
+            $translationPath = theme_path('/lang/en');
+            File::makeDirectory($translationPath, 0777, true);
 
-        // Create a folder and configure a theme
-        $this->themeFolderName = 'testing_theme_' . rtrim(base64_encode(time()), "=");
-        config()->set('view.theme', $this->themeFolderName);
-        $this->themeFolderPath = theme_path('');
-        File::makeDirectory($this->themeFolderPath);
-    }
-
-    public function tearDown(): void
-    {
-        // Cleanup the custom theme folder we created
-        File::deleteDirectory($this->themeFolderPath);
-
-        parent::tearDown();
-    }
-
-    public function test_translation_text_can_be_overriden_via_theme()
-    {
-        $translationPath = theme_path('/lang/en');
-        File::makeDirectory($translationPath, 0777, true);
-
-        $customTranslations = '<?php
+            $customTranslations = '<?php
             return [\'books\' => \'Sandwiches\'];
         ';
-        file_put_contents($translationPath . '/entities.php', $customTranslations);
+            file_put_contents($translationPath . '/entities.php', $customTranslations);
 
-        $homeRequest = $this->actingAs($this->getViewer())->get('/');
-        $homeRequest->assertElementContains('header nav', 'Sandwiches');
+            $homeRequest = $this->actingAs($this->getViewer())->get('/');
+            $homeRequest->assertElementContains('header nav', 'Sandwiches');
+        });
+    }
+
+    public function test_theme_functions_file_used_and_app_boot_event_runs()
+    {
+        $this->usingThemeFolder(function($themeFolder) {
+            $functionsFile = theme_path('functions.php');
+            app()->alias('cat', 'dog');
+            file_put_contents($functionsFile, "<?php\nTheme::listen(\BookStack\Theming\ThemeEvents::APP_BOOT, function(\$app) { \$app->alias('cat', 'dog');});");
+            $this->runWithEnv('APP_THEME', $themeFolder, function() {
+                $this->assertEquals('cat', $this->app->getAlias('dog'));
+            });
+        });
+    }
+
+    public function test_event_commonmark_environment_configure()
+    {
+        $callbackCalled = false;
+        $callback = function($environment) use (&$callbackCalled) {
+            $this->assertInstanceOf(ConfigurableEnvironmentInterface::class, $environment);
+            $callbackCalled = true;
+            return $environment;
+        };
+        Theme::listen(ThemeEvents::COMMONMARK_ENVIRONMENT_CONFIGURE, $callback);
+
+        $page = Page::query()->first();
+        $content = new PageContent($page);
+        $content->setNewMarkdown('# test');
+
+        $this->assertTrue($callbackCalled);
+    }
+
+    protected function usingThemeFolder(callable $callback)
+    {
+        // Create a folder and configure a theme
+        $themeFolderName = 'testing_theme_' . rtrim(base64_encode(time()), "=");
+        config()->set('view.theme', $themeFolderName);
+        $themeFolderPath = theme_path('');
+        File::makeDirectory($themeFolderPath);
+
+        call_user_func($callback, $themeFolderName);
+
+        // Cleanup the custom theme folder we created
+        File::deleteDirectory($themeFolderPath);
     }
 
 }
\ No newline at end of file