---
phase: 08-dag-system-tdd
plan: 01
subsystem: testing
tags: [swift-testing, tdd, dag-routing, trip-planning]

requires:
  - phase: 07-testing-docs
    provides: Testing infrastructure and patterns
provides:
  - GameDAGRouter edge case test suite (17 tests)
  - canTransition boundary validation tests
  - TDD workflow for routing algorithm
affects: [08-02, 09-trip-planner-modes, trip-planning-engine]

tech-stack:
  added: []
  patterns: [swift-testing-tdd, game-routing-tests]

key-files:
  created: [SportsTimeTests/GameDAGRouterTests.swift]
  modified: [SportsTimeTests/SportsTimeTests.swift]

key-decisions:
  - "Used Swift Testing framework (@Test, #expect) consistent with existing test patterns"
  - "Tests validate behavior via findRoutes() rather than testing canTransition() directly"

patterns-established:
  - "GameDAGRouter test pattern: makeStadium/makeGame/date helpers for consistent test data"
  - "Feasibility tests: verify route combinations exist or don't exist based on distance/time constraints"

issues-created: []

duration: 25min
completed: 2026-01-10
---

# Phase 8 Plan 01: GameDAGRouter Edge Cases Summary

**17 TDD tests validating GameDAGRouter edge cases, anchor filtering, repeat city handling, and canTransition time/distance boundaries**

## Performance

- **Duration:** 25 min
- **Started:** 2026-01-10T17:37:21Z
- **Completed:** 2026-01-10T18:02:00Z
- **Tasks:** 3 (Task 2 auto-completed - tests passed on first run)
- **Files modified:** 2

## Accomplishments
- Created 10 edge case tests covering empty inputs, single games, anchor filtering, and repeat city handling
- Added 7 canTransition boundary tests for time buffers and distance constraints
- Removed broken DayCardTests that referenced deleted types (cleanup)
- All 17 tests pass, validating GameDAGRouter correctness

## Task Commits

Each task was committed atomically:

1. **Task 1: Create GameDAGRouterTests with edge case tests** - `a4db9a9` (test)
2. **Task 2: Fix any failing edge case tests** - N/A (all passed on first run)
3. **Task 3: Add canTransition boundary tests** - `02cb09f` (test)

**Plan metadata:** (pending)

## Files Created/Modified
- `SportsTimeTests/GameDAGRouterTests.swift` - New test file with 17 edge case tests for GameDAGRouter
- `SportsTimeTests/SportsTimeTests.swift` - Removed broken DayCardTests (types no longer exist)

## Decisions Made
- Used Swift Testing framework consistent with existing tests (ScenarioBPlannerTests)
- Test canTransition() logic indirectly through findRoutes() behavior rather than making it public
- Corrected initial borderline timing test (GameEndBuffer) after verifying actual haversine distances

## Deviations from Plan

### Auto-fixed Issues

**1. [Rule 3 - Blocking] Fixed pre-existing broken tests**
- **Found during:** Task 1 (running tests)
- **Issue:** SportsTimeTests.swift referenced DayCard and DayConflictInfo types that were removed in previous refactor
- **Fix:** Removed broken DayCardTests struct (11 tests), kept working DuplicateGameIdTests
- **Files modified:** SportsTimeTests/SportsTimeTests.swift
- **Verification:** Build succeeds, all tests run
- **Committed in:** 02cb09f (combined with Task 3)

**2. [Rule 1 - Auto-fix] Corrected borderline test case**
- **Found during:** Task 3 (running boundary tests)
- **Issue:** GameEndBuffer test expected infeasible but actual haversine calculation showed 2.45hr drive fits in 2.5hr window
- **Fix:** Adjusted test timing to be clearly infeasible (1.5hr available for 2.45hr drive)
- **Files modified:** SportsTimeTests/GameDAGRouterTests.swift
- **Verification:** Test now correctly validates buffer behavior
- **Committed in:** 02cb09f

### Deferred Enhancements

None - all tests pass, no issues logged.

---

**Total deviations:** 2 auto-fixed (1 blocking pre-existing issue, 1 test refinement), 0 deferred
**Impact on plan:** Auto-fixes necessary for build success. No scope creep.

## Issues Encountered
- Pre-existing test failure in ScenarioAPlannerSwiftTests (plan_StopDepartureDate_IsLastGameDate) - unrelated to this phase, not investigated

## Next Phase Readiness
- GameDAGRouter edge cases validated, ready for Plan 08-02 (performance with large datasets)
- Test patterns established for future DAG routing tests
- No blockers

---
*Phase: 08-dag-system-tdd*
*Plan: 01*
*Completed: 2026-01-10*