Summary - Advanced testing
- Node.js course
- Advanced
- Lesson 78/83
- 5 min
Combine integration, supertest and coverage to write an API test suite.
Summary - Advanced testing
In this group you learned the advanced test tools of Node.js: writing tests with test and expect, testing Express in memory with supertest, protecting production with a test database, measuring coverage with jest --coverage, and writing E2E tests with Playwright.
Now you will combine these into a small test skeleton. The skeleton will contain a test call, an expect assertion, and a beforeEach cleaning step. This mini task shows how the test tools combine.
Test design
A test skeleton is this: cleaning with beforeEach, a test definition with test, an assertion with expect. In integration tests, an HTTP request is sent with supertest.
Flow: beforeEach(() => { /* cleaning */ }); test("user creation", () => { const result = createUser({ name: "Ayşe" }); expect(result.name).toBe("Ayşe"); });. This skeleton cleans before each test, defines a test, and asserts the result. In production, supertest is added for integration tests. On top of the test skeleton you can add coverage targets, CI/CD integration and E2E scenarios. This is the foundation of reliable software delivery.
Practice Build the test skeleton
Define beforeEach(() => { console.log("Cleaned"); }). Define test("example", () => { expect(1+1).toBe(2); }). Print "Test system ready" with console.log.
Starter code
// Define beforeEach and test
// write here
// Print "Test system ready"
// write hereSample solution
beforeEach(() => {
console.log("Cleaned");
});
test("example", () => {
expect(1+1).toBe(2);
});
console.log("Test system ready");Expected output
Test system ready
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 What pieces does the test skeleton combine?
test + expect + beforeEach- Only require
- test, expect and beforeEach Correct answer
- Only console.log
- Only coverage
Explanation: test + expect + beforeEach combine.
2 Match each tool to its role
| Term | Meaning |
|---|---|
test |
Defines a test |
expect |
Does assertions |
beforeEach |
Cleans before each test |
supertest |
Tests Express in memory |