Mutation testing (@tao.js/react)

StrykerJS + Jest for the React adapter package.

Run

From repo root:

pnpm test:mutation:react

Or from this package:

pnpm test:mutation

HTML/JSON reports land in reports/mutation/ (gitignored).

Notes

• Config: stryker.config.json — inPlace: true so Jest can resolve the monorepo jest.preset.cjs and shared React moduleNameMapper.
• testEnvironment is set explicitly on the package Jest config and as Stryker’s jsdom env wrapper — Stryker does not merge preset-provided testEnvironment under perTest coverage analysis.
• Barrel re-exports (index.js, all.js, orig.js) are excluded from mutation (same as coverage).
• Disable equivalent mutants with // Stryker disable … : reason (colon required; place disable before a try, not inside it).
• Latest score (2026-07-18): 100% (270 killed, 11 timeout, 0 survived; thresholds high=95).
• Optional debug console paths and redundant Provider-{} null checks are Stryker-disabled as equivalent.

See @tao.js/core (packages/tao/README.mutation.md) for the pattern used to raise scores.