---
phase: 18-api-route-tests
plan: 01
subsystem: testing
tags: [vitest, api-routes, fs-mocking, fetch-mocking, next.js]

# Dependency graph
requires:
  - phase: 17-component-tests
    provides: React Testing Library patterns and vitest configuration
provides:
  - API route testing patterns with fs/promises mocking
  - NextRequest/NextResponse mocking patterns
  - fetch mocking for HTTP URL handling
  - Deduplication test patterns
affects: [18-02, 18-03, 18-04, 18-05]

# Tech tracking
tech-stack:
  added: []
  patterns: [fs-mocking-with-factory-functions, nextrequest-mocking]

key-files:
  created:
    - src/app/api/workflow/__tests__/route.test.ts
    - src/app/api/save-generation/__tests__/route.test.ts
  modified: []

key-decisions:
  - "Use factory function pattern for vi.mock with named exports (mockStat, mockMkdir, etc.)"
  - "Mock NextRequest with json() and nextUrl.searchParams helpers"

patterns-established:
  - "fs mocking: Define mock functions at module scope, wire in vi.mock factory"
  - "API route testing: Import POST/GET handlers directly, create mock request objects"

issues-created: []

# Metrics
duration: 4 min
completed: 2026-01-13
---

# Phase 18 Plan 01: File I/O Routes Summary

**API route tests for workflow and save-generation with fs/promises mocking patterns established**

## Performance

- **Duration:** 4 min
- **Started:** 2026-01-13T14:45:00Z
- **Completed:** 2026-01-13T14:49:00Z
- **Tasks:** 2
- **Files modified:** 2

## Accomplishments
- Created 14 tests for workflow route (POST save, GET validation)
- Created 15 tests for save-generation route (save, deduplication, MIME types)
- Established fs/promises mocking pattern using factory functions
- Established fetch mocking for HTTP URL handling

## Task Commits

Each task was committed atomically:

1. **Task 1: Create workflow route tests** - `f7625ed` (test)
2. **Task 2: Create save-generation route tests** - `17ee68c` (test)

**Plan metadata:** (this commit)

## Files Created/Modified
- `src/app/api/workflow/__tests__/route.test.ts` - 14 tests covering POST save and GET validation
- `src/app/api/save-generation/__tests__/route.test.ts` - 15 tests covering save, deduplication, validation

## Decisions Made
- Used factory function pattern for vi.mock to define mock functions at module scope
- Mock NextRequest with json() and nextUrl.searchParams helpers rather than full request objects

## Deviations from Plan

### Auto-fixed Issues

**1. [Rule 3 - Blocking] Fixed mocking pattern for vitest**
- **Found during:** Task 1 (workflow route tests)
- **Issue:** vi.mocked(fs.stat).mockResolvedValue() failed - vitest auto-mocking doesn't expose mock functions directly
- **Fix:** Defined mock functions at module scope (const mockStat = vi.fn()) and wired them in vi.mock factory
- **Files modified:** src/app/api/workflow/__tests__/route.test.ts
- **Verification:** Tests pass with new mocking pattern
- **Committed in:** f7625ed

**2. [Rule 3 - Blocking] Fixed missing matcher**
- **Found during:** Task 2 (save-generation route tests)
- **Issue:** toEndWith() matcher not available in vitest/chai
- **Fix:** Used expect(data.filename.endsWith(".png")).toBe(true) instead
- **Files modified:** src/app/api/save-generation/__tests__/route.test.ts
- **Verification:** Tests pass with boolean assertion
- **Committed in:** 17ee68c

---

**Total deviations:** 2 auto-fixed (2 blocking), 0 deferred
**Impact on plan:** Both auto-fixes were necessary for tests to function. No scope creep.

## Issues Encountered
None - plan executed successfully with blocking issues resolved inline.

## Next Phase Readiness
- fs mocking pattern established for use in subsequent API route test plans
- fetch mocking pattern established for HTTP URL handling
- Ready for 18-02 (LLM route tests)

---
*Phase: 18-api-route-tests*
*Completed: 2026-01-13*