Tesing in JS

Manual Vs automated testing

Types of test

• Unit test: testing individual building blocks of code in isolation. There are hundreds of unit tests. Most important.
• Integration test: test combination of multiple building blocks of code. These tests are smaller in number.
• End to end test: test complete scenario in the app as user experience them. Project typically contains only a few e2e tests.

We should test success and error cases.

Jest

• Used to run unit test.

React testing library

• Used to render/simulate the react components.

• Both the above tools are installed by create react app.

• For each component create a xxx.test.js file.

• Run npm test.

test('description', () => {
  // Test
  render()
  expect().toBeInTheDocument()
})

Test suite Vs test

describe("test group description", ()=>{

test1;
test2;
....
}

The three As of testing

• Arrange
• Act
• Assert