init]テスト作成完了

.gitignore

@@ -5,6 +5,7 @@
 .idea/
 dist/
 .serverless/
+coverage/
 
 mdstream_project_summary.txt
 

backend/__mocks__/@aws-sdk/client-s3.ts

@@ -0,0 +1,20 @@
+// __mocks__/@aws-sdk/client-s3.ts
+
+// @ts-nocheck  ← ここでも型チェック無効化してOK
+import { jest } from '@jest/globals';
+
+// 何でも受け取れるモック
+export const mockSend = jest.fn();
+
+export class S3Client {
+    constructor() {}
+    send = mockSend;
+}
+
+export class ListObjectsV2Command {
+    constructor(args) {}
+}
+
+export class GetObjectCommand {
+    constructor(args) {}
+}

backend/jest.config.js

@@ -0,0 +1,7 @@
+// backend/jest.config.js
+/** @type {import('jest').Config} */
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  testMatch: ['**/tests/**/*.test.ts']
+}