// in package.json

{

 "scripts": {

    "coverage": "yarn test --coverage --watchAll --collectCoverageFrom='src/components/**/*.{js,jsx}' --collectCoverageFrom='!src/components/**/*{types,stories,constants,test,spec}.{js,jsx}' "

 },

​

 "jest": { 

   "coverageThreshold": { 

    "global": {

        "branches": 80, 

        "functions": 80, 

        "lines": 80, 

        "statements": -10

     }

   }

 }

}

// Command 

npm run test -- --coverage 

​

// If you wanna watch 

npm run test -- --coverage --watchAll=true 

​

// or 

​

npm run test -- --coverage --watchAll=true 

​

​

# in package.json

# "scripts": {

#     "test": "jest --coverage"

# },

​

# using yarn

yarn test

​

# using npm

npm run test

jest --watch #runs jest -o by default

jest --watchAll #runs all tests