mock-module

To prevent cross-test pollution when mocking Node.js built-in modules, you must spread the real module's exports when creating mocks. This ensures proper test isolation and eliminates state leakage between test cases.

Node.js unit tests fail inconsistently when mocking the fs module due to state leakage from improper mocking. Spreading the real module exports isolates the test environment and ensures consistent unit test results.

The best way to mock Node.js built-in modules like path or http without leaking state is to spread the real module's exports during mock creation. This prevents cross-test pollution and ensures reliable test outcomes.

Improper mocking of Node.js built-in modules does break CI/CD pipelines by causing flaky and unreliable test results. Spreading real module exports resolves this state leakage and stabilizes the test suite.

To isolate test environments for Node.js applications using built-in modules, spread the real module's exports when generating mocks. This prevents cross-test pollution and maintains consistent test runs.