Non-Deterministic Test
A test whose outcome can vary between runs on unchanged code, typically due to timing, ordering, or shared state.
What is Non-Deterministic Test?
What is Non-Deterministic Test?
A non-deterministic test is one that can pass or fail unpredictably even when nothing in the code has changed, usually because it races the UI, depends on execution order, or shares mutable state with other tests. This is exactly what makes a test flaky and untrustworthy, since a failure no longer reliably signals a defect. Eliminating non-determinism—through proper waiting, isolation, and stable locators—is the difference between a suite teams rely on and one they learn to ignore. QI prioritizes deterministic runs precisely to avoid this trap.