diff --git a/tests/fixtures.mts b/tests/fixtures.mts
index e6f12ad..a6ff7f7 100644
--- a/tests/fixtures.mts
+++ b/tests/fixtures.mts
@@ -1,11 +1,11 @@
 import * as base from '@playwright/test';
-import { _electron as electron } from 'playwright';
+import {_electron as electron, Page, ElectronApplication} from 'playwright';
 import { join } from 'path';
 import { main } from '../package.json';
 import TestUtil from './testUtil.mjs';
 
-let appElectron;
-let page;
+let appElectron: ElectronApplication;
+let page: Page;
 
 const __cwd = process.cwd();
 const __isCiProcess = process.env.CI === 'true';
@@ -52,7 +52,7 @@ export const beforeAll = async () => {
     };
   });
 
-  await base.expect(evaluateResult.packaged, 'app is not packaged').toBe(false);
+  base.expect(evaluateResult.packaged, 'app is not packaged').toBe(false);
 };
 
 export const afterAll = async () => {
diff --git a/tests/testUtil.mts b/tests/testUtil.mts
index b036933..2846581 100644
--- a/tests/testUtil.mts
+++ b/tests/testUtil.mts
@@ -8,13 +8,13 @@ export default class TestUtil {
 
   _testScreenshotPath: string;
 
-  constructor(page, testInfo, testScreenshotPath) {
+  constructor(page: Page, testInfo: TestInfo, testScreenshotPath: string) {
     this._page = page;
     this._testInfo = testInfo;
     this._testScreenshotPath = testScreenshotPath;
   }
 
-  async captureScreenshot(pageInstance, screenshotName) {
+  async captureScreenshot(pageInstance: Page, screenshotName: string) {
     if (!pageInstance) {
       return;
     }
@@ -28,13 +28,13 @@ export default class TestUtil {
     }
   }
 
-  async onTestError(error) {
+  async onTestError(error: Error) {
     const titleLists = [...this._testInfo.titlePath];
     titleLists.shift();
     const title = titleLists.join('-');
 
     await this.captureScreenshot(this._page, `${title}_${Date.now()}`);
 
-    return new Error(error);
+    return new Error(error.message);
   }
 }