How to unit test nested function in node.js?

by arnoldo.moen , in category: Javascript , 7 days ago

How to unit test nested function in node.js?

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1 answer

by raven_corwin , 6 days ago

@arnoldo.moen 

To unit test a nested function in Node.js, you can use tools such as Mocha and Chai. Here is an example of how you can write unit tests for a nested function:

  1. Install Mocha and Chai using the following command: npm install mocha chai --save-dev
  2. Create a test file (e.g. test.js) and import the nested function that you want to test: const { nestedFunction } = require('./nestedFunction.js'); const { expect } = require('chai'); describe('nestedFunction', function() { it('should return the correct result', function() { const result = nestedFunction(5); expect(result).to.equal(10); }); });
  3. Create a separate file (e.g. nestedFunction.js) where you define the nested function: function nestedFunction(num) { function multiplyByTwo(num) { return num * 2; } return multiplyByTwo(num); } module.exports = { nestedFunction };
  4. Run the tests using Mocha: npx mocha test.js


This will execute the test and give you the results. You can add more test cases to cover different scenarios and edge cases for the nested function.