How do I prevent node from sending errors to the console? - npm

Question

Working on a React project.
I start up my environment using npm start. I then start my testing infrastructure using npm test in a different terminal. While my tests are running, errors are generated and printed in the terminal that my environment is running in.
npm start
Compiled successfully!
You can now view v2 in the browser.
Local: http://localhost:3000
Note that the development build is not optimized.
To create a production build, use yarn build.
Open another terminal and run npm test
Test Suites: 1 passed, 1 total
Tests: 3 passed, 3 total
Snapshots: 0 total
Time: 2.415s
Ran all test suites.
Yet, some UI errors that the tests generate appear in the terminal for my local environment
Compiled successfully!
You can now view v2 in the browser.
Local: http://localhost:3000
Note that the development build is not optimized.
To create a production build, use yarn build.
[HPM] Error occurred while trying to proxy request /directory from localhost:3000 to <TARGET> (ECONNRESET) (https://nodejs.org/api/errors.html#errors_common_system_errors)
[HPM] Error occurred while trying to proxy request /directory from localhost:3000 to <TARGET> (ECONNRESET) (https://nodejs.org/api/errors.html#errors_common_system_errors)
[HPM] Error occurred while trying to proxy request /directory from localhost:3000 to <TARGET> (ECONNRESET) (https://nodejs.org/api/errors.html#errors_common_system_errors)
[HPM] Error occurred while trying to proxy request /directory from localhost:3000 to <TARGET> (ECONNRESET) (https://nodejs.org/api/errors.html#errors_common_system_errors)
[HPM] Error occurred while trying to proxy request /directory from localhost:3000 to <TARGET> (ECONNRESET) (https://nodejs.org/api/errors.html#errors_common_system_errors)
How do I prevent errors - and anything else for that matter - from being printed out to the terminal where I started my dev environment?

Answer 1

looking at the output of your npm test, it seems like you are using jest, which has a support for configuring setup files
A list of paths to modules that run some code to configure or set up the testing framework before each test file in the suite is executed.
you can utilize it by pointing to a file, where you can mock the implmentation for console.
add to jest.config.js the following
module.exports = {
setupFilesAfterEnv: ['./jest.setup.js'],
};
then in jest.setup.js file
global.beforeAll(() => {
// disable console.error for clarity
console.error = jest.fn().mockImplementation(() => {});
});
note that it will achieve what you desire only if the module that prints to the console during the testing is using console.error(). otherwise, you might need to mock other functions, such as console.info(), console.log(), console.debug()