testing

/specseal:testing — put each test where it can actually fail

Coverage counts what ran, not what was checked, so a suite can be green and prove nothing. Two questions decide the shape: at which level can this break be observed, and would the test fail if the behavior changed.

The pyramid below is general; its middle tier is where projects differ most, so read the examples as one filling. What sits there is whatever this project's parts have to agree on to work — a service's database and request handlers, a client's screens against a fake backend, a CLI's argument parsing through to its exit codes, a library's public surface against a real consumer, a pipeline's stages against fixture data.

Test Pyramid

Unit Tests (base - most tests here)

• Pure functions, business logic
• Fast, isolated, no external deps
• Mock at boundaries only

Integration Tests (middle)

• Component interactions — the seams this project actually has
• Real collaborators where the seam is the point (a test database or container, a fake server, a temp filesystem, a simulator)
• Examples by project kind: database queries and request handlers; a screen driven against a stubbed API; argument parsing through to exit codes; a library exercised the way a caller would

E2E Tests (top - fewest tests here)

• Critical user flows only
• Login, checkout, core workflows
• Slower, run less frequently

Test Quality Checklist

• Tests have descriptive names (should_X_when_Y)
• Each test checks ONE thing
• Tests are independent (no ordering dependency)
• Tests cover happy path AND edge cases
• Tests cover error paths
• No test logic complexity (no if/loops in tests)
• Assertions are specific (not just "no error")

Rules

• Write failing test BEFORE fixing bugs
• Don't test implementation details, test behavior
• Don't mock what you don't own (wrap it instead)
• Keep tests fast (seconds, not minutes)
• Coverage target: focus on critical paths, not percentages

Output

## Test Strategy: [scope]

**Coverage Gaps**: [what's not tested]
**Priority Tests**: [what to add first]
**Test Plan**:
1. [test description] - [type: unit/integration/e2e]
2. ...

[Generated test code if requested]