Jest Testing Workflow

Overview

Use this skill to design and run Jest suites that are stable, meaningful, and decision-ready for merge gates.

Scope Boundaries

• Use this skill when the task matches the trigger condition described in description.
• Do not use this skill when the primary task falls outside this skill's domain.

Shared References

• Trigger examples and expected deliverables:
  • references/trigger-and-examples.md
• Mock boundary decision rules:
  • references/mock-boundary-decision-rules.md
• Determinism rules:
  • references/jest-determinism-rules.md

Templates And Assets

• Test plan template:
  • assets/jest-test-plan-template.md
• Command profile template:
  • assets/jest-command-profile-template.md
• Flake triage checklist:
  • assets/jest-flake-triage-checklist.md

Inputs To Gather

• Change scope and affected JS/TS modules.
• Runtime assumptions (node/jsdom) and mock boundaries.
• CI constraints for runtime and coverage gates.
• Known flaky areas (async timers, shared state, external dependencies).

Deliverables

• Jest test strategy with mock/timer/environment policy.
• Assertion matrix for happy, edge, and failure paths.
• Local-fast and CI-full command profiles.
• Residual flakiness risk log with owner and next action.

Workflow

1. Clarify decision question and mandatory quality constraints.
2. Draft strategy using assets/jest-test-plan-template.md.
3. Decide mock boundaries with references/mock-boundary-decision-rules.md.
4. Define execution profiles in assets/jest-command-profile-template.md.
5. Stabilize async/timer behavior with references/jest-determinism-rules.md.
6. Run checks and close with assets/jest-flake-triage-checklist.md.

Quality Standard

• Trigger fit and test depth are explicit.
• Mock strategy preserves behavior confidence for critical paths.
• Async/timer behavior is deterministic in local and CI runs.
• Evidence is reproducible with exact commands and artifacts.

Failure Conditions

• Stop when mock strategy hides behavior that must be integration-visible.
• Stop when command profile is not reproducible across local/CI.
• Escalate when flakiness persists after deterministic controls.