Problem
Nightly run 33251376747 reported 152 missed mutants in complete artifacts from shards 1, 3, 4, 18, 23, 24, 26, and 30. At current main 08f729b9, 149 mutation source lines remain byte-identical. Three sites were retired by subsequent production changes: the old fallback condition in rate_limit::enforce and two body-limit arithmetic expressions replaced by route descriptors.
Shards 2 and 9 lost their runners with mutation steps still marked in progress and produced no logs or artifacts. Shard 19 was canceled and uploaded nothing. Shards 25 and 27 received explicit runner shutdown signals after logging 12 and 9 missed mutants, respectively; all 21 logged source lines remain on current main, but neither log is a complete shard inventory. Runner loss explains missing reports, not the mutants that completed and survived tests.
Work groups
Required changes
- Verify only the named mutants in each group against current main before opening a child issue or changing code.
- Add public-behavior coverage for current survivors, fix any behavior defect that inspection exposes, and remove production code only when reachability analysis proves it dead.
- Keep test-support gaps separate from production gaps.
- Do not add mutation exclusions, retries, skips, timeouts, filters, conditional hiding, or CI-only workarounds.
Acceptance criteria
- Every complete-report mutant and every observed interrupted-log mutant is either caught on current main, retired with a documented code change, or closed by a focused fix.
- Each child fix has full changed-line coverage and passes its affected test and static gates.
- A later scheduled mutation run completes every shard and reports no missed mutants.
Problem
Nightly run 33251376747 reported 152 missed mutants in complete artifacts from shards 1, 3, 4, 18, 23, 24, 26, and 30. At current main
08f729b9, 149 mutation source lines remain byte-identical. Three sites were retired by subsequent production changes: the old fallback condition inrate_limit::enforceand two body-limit arithmetic expressions replaced by route descriptors.Shards 2 and 9 lost their runners with mutation steps still marked in progress and produced no logs or artifacts. Shard 19 was canceled and uploaded nothing. Shards 25 and 27 received explicit runner shutdown signals after logging 12 and 9 missed mutants, respectively; all 21 logged source lines remain on current main, but neither log is a complete shard inventory. Runner loss explains missing reports, not the mutants that completed and survived tests.
Work groups
Required changes
Acceptance criteria