不一定。可以采用测试驱动开发（TDD）的方法，由开发人员编写必要的单元测试，而功能和集成测试可以由专门的测试人员编写。下面的代码示例演示了如何在Node.js中使用Mocha和Chai库进行单元测试：

安装依赖：

npm install --save-dev mocha chai

book.js文件：

class Book {
  constructor(title, author) {
    this.title = title;
    this.author = author;
  }

  getTitle() {
    return this.title;
  }

  getAuthor() {
    return this.author;
  }
}

module.exports = Book;

book.test.js文件：

const expect = require('chai').expect;
const Book = require('./book');

describe('Book', () => {
  describe('#getTitle', () => {
    it('should return the title of the book', () => {
      const book = new Book('The Catcher in the Rye', 'J.D. Salinger');
      expect(book.getTitle()).to.equal('The Catcher in the Rye');
    });
  });

  describe('#getAuthor', () => {
    it('should return the author of the book', () => {
      const book = new Book('The Catcher in the Rye', 'J.D. Salinger');
      expect(book.getAuthor()).to.equal('J.D. Salinger');
    });
  });
});

在控制台中输入以下命令运行测试：

./node_modules/mocha/bin/mocha

输出：

Book
  #getTitle
    ✓ should return the title of the book
  #getAuthor
    ✓ should return the author of the book

2 passing (9ms)