test(upload): add unit tests for useVideoUpload hook

[DSanich]

Summary

useVideoUpload is a critical hook that handles all video recording and upload logic, yet it has zero test coverage. This hook is responsible for:

• Combining multi-segment recordings into a single video
• Extracting video duration from a Blob via a DOM <video> element
• Uploading to Blossom servers via useUploadFile
• Tracking upload progress (0 → 0.25 → 1.0)
• Cleaning up objectURL references after upload
• Showing toast notifications on success and error

Without tests, regressions in the upload pipeline are silent and hard to catch in CI.

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Current behaviour

• useVideoUpload.ts (~174 lines) has no colocated useVideoUpload.test.ts
• There is an active known limitation inside combineSegments: when segments.length > 1, only the first segment is used and a toast is shown. This behaviour is intentional for MVP but is not verified by any assertion — so if the logic ever silently changes, nothing will catch it.

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What needs to be tested

1. combineSegments — single segment (happy path)

• Returns the original blob, blobUrl, and resolved duration
• getVideoDuration is called once
• No toast is shown

2. combineSegments — multiple segments (current MVP behaviour)

• Shows a "Multi-clip recording." toast with the correct description
• Returns only the first segment's blob / blobUrl
• getVideoDuration is called on the first segment

3. combineSegments — empty array

• Throws 'No segments to combine'

4. getVideoDuration — success

• Creates a <video> element, sets src to an objectURL
• Resolves with video.duration * 1000 (milliseconds)
• Calls window.URL.revokeObjectURL after resolution

5. getVideoDuration — error

• Rejects with 'Failed to load video metadata' when video.onerror fires
• Calls window.URL.revokeObjectURL on the error path too

6. uploadVideo — success flow

• Sets uploadProgress to 0 → 0.1 → 0.25 → 1
• Calls uploadFile with a File built from the combined blob
• Extracts the URL from the returned tags array ([['url', 'https://...']])
• Returns { url, tags, duration }
• Revokes all blob URLs on completion

7. uploadVideo — upload returns no URL tag

• Throws 'Upload succeeded but no URL returned'

8. uploadVideo — uploadFile rejects

• Sets uploadProgress back to 0
• Re-throws the error
• Shows a destructive toast: 'Upload snagged.'

9. isUploading flag

• Is false initially
• Becomes true while uploadVideoMutation is pending
• Returns to false after completion

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Mocking strategy

Follow the existing pattern from useProfileStats.test.ts. Key mocks needed:

vi.mock('@/hooks/useUploadFile', () => ({ useUploadFile: vi.fn() }));
vi.mock('@/hooks/useToast', () => ({ useToast: vi.fn(() => ({ toast: vi.fn() })) }));
Object.defineProperty(window, 'URL', {
  value: { createObjectURL: vi.fn(() => 'blob:mock-url'), revokeObjectURL: vi.fn() },
});

getVideoDuration uses document.createElement('video') — mock it by dispatching loadedmetadata / error events on the created element, or by stubbing document.createElement.

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Acceptance criteria

• File src/hooks/useVideoUpload.test.ts created
• All 9 scenarios above have at least one it(...) block
• No real network calls or DOM video decoding in tests
• Tests pass with npx vitest run src/hooks/useVideoUpload.test.ts
• No new TypeScript errors (npx tsc --noEmit)

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Related files

File	Role
src/hooks/useVideoUpload.ts	The hook under test
src/hooks/useUploadFile.ts	Blossom uploader — must be mocked
src/hooks/useToast.ts	Toast notifications — must be mocked
src/hooks/useProfileStats.test.ts	Reference for test style / mock setup
src/test/setup.ts	Global Vitest setup (jsdom)

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Notes

The multi-segment limitation (scenarios 2 and 3 above) is a known MVP shortcut, not a bug to fix in this issue. The goal of these tests is to document and lock in the current behaviour so that future work on FFmpeg.wasm concatenation has a clear regression baseline.

[DSanich]

@NotThatKindOfDrLiz @rabble @jalcine @mbradley I continued to explore the project's codebase and discovered that such an important piece of functionality isn't covered by tests. What do you think about this? I'd be happy to look into it and share the PR with you.

[DSanich]

@jalcine @NotThatKindOfDrLiz Hi! I've added the necessary tests in this PR, please take a look at it.