TASK-059-design-tests-expose-unimplemented-zig.md

TASK-059: Design and Add Tests to Expose Unimplemented Zig Functionality

Status

• Planned
• Assigned
• In Progress
• Blocked (reason: ...)
• Complete

Priority

medium

Assigned To

subagent (general)

Parent Docs / Cross-links

• Test oracle design: research/zig-cr/10-test-oracle.md
• Feature matrix: research/zig-cr/90-feature-matrix.md
• Gap backlog: research/zig-cr/92-gap-backlog.md
• Existing test harnesses: zig/harness/
• C oracle tests: core/c/

Description

Design and implement additional tests to systematically expose any gaps in the Zig implementation that aren't caught by existing test suites.

Focus areas:

1. Edge cases and error conditions: Test boundary conditions, error handling, and failure modes
2. Multi-table scenarios: Complex interactions between multiple CRR tables
3. Merge conflict resolution: All tie-breaker paths (cl/col_version/value/site_id)
4. Clock semantics: dbVersion/pendingDbVersion/seq invariants across transactions
5. Serialization formats: PK blob packing/unpacking edge cases
6. Virtual table operations: xUpdate paths, transaction boundaries, best-index scenarios
7. Hook chaining: Commit/rollback hook interactions with other extensions
8. Schema evolution: as_crr/as_table with different table configurations
9. Performance characteristics: Large UNION query scaling, statement cache effectiveness

Each test should:

• Be deterministic and reproducible
• Have clear pass/fail criteria
• Document what functionality it's validating
• Run quickly (avoid long-running stress tests in CI)

Files to Modify

• zig/harness/ (new test scripts or extensions to existing ones)
• zig/src/ (add unit tests in relevant modules)
• research/zig-cr/92-gap-backlog.md (document test coverage improvements)

Acceptance Criteria

• Identify at least 5-10 additional test scenarios not covered by existing tests
• Document the test design in the Progress Log with rationale
• Implement the new tests
• Tests successfully expose at least one previously undetected gap (if any exist)
• All new tests pass (or are marked as expected failures with task cards created for fixes)
• Test documentation explains what each test validates and why it's important
• Tests are integrated into existing test harness (make test-* targets)

Progress Log

2025-12-17

• Task created to improve test coverage and expose implementation gaps
• Current test status: 154/154 MVP tests passing per gap backlog
• C oracle harness: 19/20 tests pass (fract_as_ordered stub causes 1 failure)
• Need to design tests that go beyond existing coverage

Completion Notes

[fill in when done]