test(social): unit tests for useOptimisticLike and useOptimisticRepost

[DSanich]

Summary

Add hook-level tests for useOptimisticLike and useOptimisticRepost, which optimistically update TanStack Query cache for video-social-metrics and video-user-interactions, then publish kind 7 / kind 16 / kind 5 events via useNostrPublish. These paths are high-traffic and easy to break silently (wrong keys, missing rollback).

Problem

• Both hooks live in src/hooks/useOptimisticLike.ts and src/hooks/useOptimisticRepost.ts with no colocated tests.
• Components only mock these hooks (FullscreenFeed.test.tsx, etc.), so cache updates, rollback on failure, and published event shapes are untested.
• useOptimisticRepost depends on useRepostVideo as well — interactions between mutations need explicit assertions.

Expected outcome

renderHook + mocked useQueryClient, useNostrPublish, useToast, and for repost useRepostVideo, verifying:

1. Optimistic cache deltas for like/repost counts and interaction flags.
2. publishEvent / repostVideo called with expected kinds and tags on toggle-on.
3. Kind 5 delete path on undo-like / undo-repost when event IDs exist.
4. Rollback restores previous cache snapshot when publishEvent throws (match current catch behaviour).

What needs to be tested

useOptimisticLike.toggleLike

• Unlike: metrics likeCount decrements (floored at 0); interactions hasLiked: false, likeEventId: null; kind 5 published with e pointing at currentLikeEventId when provided.
• Like: metrics increment; interactions updated; kind 7 (or actual kind used in source) published — assert against useOptimisticLike implementation.
• Error path: after forced rejection from publishEvent, prior metrics/interactions restored from snapshots.

useOptimisticRepost.toggleRepost

• Un-repost: repost count decrement; publishEvent kind 5 with delete tags when currentRepostEventId set.
• Repost: repostVideo invoked with originalPubkey / vineId; optimistic metrics/interactions updated.
• Error path: rollback behaviour consistent with source.

(Exact event kinds and tag shapes must match current files — do not assume from this issue text alone.)

Mocking strategy

• vi.mock('@/hooks/useNostrPublish') → { mutateAsync: vi.fn() }.
• vi.mock('@/hooks/usePublishVideo') → expose useRepostVideo with mutateAsync: vi.fn() for repost tests.
• Instantiate real QueryClient or mock setQueryData/getQueryData — prefer real QueryClient for integration fidelity (same pattern as other hook tests).

Acceptance criteria

• src/hooks/useOptimisticLike.test.ts and src/hooks/useOptimisticRepost.test.ts (or one file if preferred).
• No live relays; all nostr traffic mocked.
• npm run test + npx tsc --noEmit clean.

Related files

File	Role
src/hooks/useOptimisticLike.ts	Like / unlike
src/hooks/useOptimisticRepost.ts	Repost / un-repost
src/hooks/useVideoSocialMetrics.ts	Types for metrics cache shape

Notes

• Keep tests behaviour-driven: assert public outcomes (cache + mocked publish calls), not internal debugLog strings.
• If rollback is incomplete in production, tests should document current behaviour and file a follow-up bug — do not “fix” behaviour inside the test-only PR unless trivial.

[DSanich]

Start working on it

[DSanich]

@jalcine @rabble @NotThatKindOfDrLiz Added unit tests for useOptimisticLike and useOptimisticRepost. Could you look at this.

#345