flaky-test-diagnosis

To find the root cause of a flaky test, run the test multiple times to confirm flakiness, then analyze failure patterns to classify the issue across timing, state leakage, resource contention, order dependency, or external dependencies. This isolates the exact trigger for remediation.

Common types of flaky tests include failures caused by timing issues, test state leakage, resource contention, order dependency, and external dependencies. Identifying which of these patterns is causing the failure is the first step in systematic diagnosis and stabilization.

The best way to isolate flaky tests without breaking your suite is to follow a quarantine and verification workflow. This approach stabilizes the overall test suite by removing the unstable tests, allowing you to fix the root cause and prevent future regressions safely.

To verify a fix resolved a flaky test, perform post-fix validation through repeated test runs. Running the test suite multiple times after applying the remediation ensures the failure pattern is gone and CI/CD reliability is restored.

Order dependency causes tests to pass locally but fail in CI/CD when tests rely on execution sequence or shared state from previous runs. Diagnosing this failure pattern helps isolate the state leakage and document the root cause for remediation.