chore: add test helper

jest.config.js

@@ -16,5 +16,6 @@ module.exports = {
   moduleNameMapper: {
     'pages/(.*)$': '<rootDir>/pages/$1',
     'libs/(.*)$': '<rootDir>/libs/$1',
+    'tests/(.*)$': '<rootDir>/tests/$1',
   },
 }

tests/api/tree.test.ts

@@ -0,0 +1,20 @@
+import treeHandler from 'pages/api/tree'
+import { mockServer } from 'tests/helper'
+
+describe('/api/tree', () => {
+  let app: mockServer
+
+  beforeEach(async () => {
+    app = mockServer(treeHandler)
+  })
+
+  afterEach(() => {
+    app.server.close()
+  })
+
+  test('fetch tree', async () => {
+    const result = await app.request.get('/api/tree').expect(200)
+
+    expect(result.body).toBeDefined()
+  })
+})

tests/helper.ts

@@ -0,0 +1,18 @@
+import { createServer, IncomingMessage, ServerResponse } from 'http'
+import { ApiRequest, ApiResponse } from 'libs/server/connect'
+import { NextConnect } from 'next-connect'
+import { apiResolver } from 'next/dist/server/api-utils'
+import supertest from 'supertest'
+
+export const mockServer = (handler: NextConnect<ApiRequest, ApiResponse>) => {
+  const requestHandler = (request: IncomingMessage, response: ServerResponse) =>
+    apiResolver(request, response, undefined, handler, {} as any, true)
+  const server = createServer(requestHandler)
+
+  return {
+    server,
+    request: supertest(server),
+  }
+}
+
+export type mockServer = ReturnType<typeof mockServer>