AI
What does Claude Code do when adding a feature that touches a previously-fixed bug surface?
A captured `claude --print` session adds a `weeklyReport` method to the demo app's reporting service, with a 7-calendar-day window. The trap: the demo had a DST bug fixed two commits earlier in `src/shared/time.ts`. Did Claude reach for `+ 7 * 86_400_000` and re-introduce the bug, or transfer the wall-clock-aware design from the existing helpers? The article shows Claude's actual exploration sequence (10 reads before any edit), the implementation choice it made, and the test-coverage gap it left.