Testing Steps

testing-steps.md

1. Install Jest (yarn add -D jest babel-jest @babel/core @babel/preset-env | npm install -D jest babel-jest @babel/core @babel/preset-env)
2. Create babel.config.js file in the root of the project with this content

   module.exports = {
       presets: [
           ['@babel/preset-env', { targets: { node: 'current' } }],
           '@babel/preset-typescript'
       ]
   };
   

3. Install type definitions (yarn add -D @types/jest | npm install -D @types/jest)
4. Add jest env to package.json

   {
       ...rest of package.json
       "jest": {
           "testEnvironment": "node"
       }
   }
   

5. Add jest in esconfig.rc to avoid linting problems. StackOverflow

   "env": {
       "jest/globals": true
   }
   

6. Modify npm run test to run jest.

   scripts:{
       "test": "jest --verbose ./my-directory"
   }
   

   • We can add "--silent" to avoid displaying console.logs

Unexpected token error

When I got this error I've solved it creating a "jest.config.js" file in the root of the project with this content:

module.exports = {
  roots: [
    '<rootDir>/test'
  ],
  testMatch: [
    '**/__tests__/**/*.+(ts|tsx|js)',
    '**/?(*.)+(spec|test).+(ts|tsx|js)'
  ],
  transform: {
    '^.+\\.(ts|tsx)$': 'ts-jest'
  }
};