Write integration tests for ScreenshotCaptureUtility
epic-annual-impact-summary-foundation-task-014 — Write Flutter integration tests (running on device/emulator) for ScreenshotCaptureUtility: captureWidget returns a non-empty Uint8List, PNG header bytes are valid, pixel ratio parameter affects output dimensions, captureToFile writes a readable file to temp directory, and shareWidget does not throw when share sheet is dismissed. Verify no memory leaks by checking RepaintBoundary cleanup after capture.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 2 - 518 tasks
Can start after Tier 1 completes
Implementation Notes
The integration test file must live in the `integration_test/` directory and import `package:integration_test/integration_test.dart`. Use `testWidgets()` from integration_test. To verify PNG dimensions from IHDR: bytes 16-19 are width (big-endian uint32), bytes 20-23 are height — parse with `ByteData.sublistView(bytes.buffer.asByteData(), 16, 24)` and `byteData.getUint32(0, Endian.big)`. For the memory stability test, run in a `for` loop and check `ProcessInfo.currentRss` before and after; flag if growth exceeds 20 MB.
For shareWidget, wrap in a try/catch and use `expect(threw, isFalse)` rather than attempting to interact with the native share sheet UI (which is outside Flutter's widget tree). Add tearDown to delete any temp files created during each test using `Directory(tempDir.path).listSync().where((f) => f.path.endsWith('.png')).forEach((f) => f.deleteSync())`. Ensure the test app's AndroidManifest.xml includes the FileProvider configuration required by share_plus.
Testing Requirements
Flutter integration tests using the integration_test package, executable via `flutter test integration_test/screenshot_capture_utility_test.dart` on a connected device or emulator. Use IntegrationTestWidgetsFlutterBinding.ensureInitialized() at test entry point. Create a minimal test harness widget (SizedBox with a Container of known dimensions and solid color) wrapped in a RepaintBoundary with a known GlobalKey. Test groups: 'output validity', 'pixel ratio scaling', 'file I/O', 'share sheet', 'memory stability'.
For memory test, record dartVM.memory before and after 10 captures. For share sheet test, use the MethodChannel mock approach or accept that the share sheet cannot be dismissed programmatically and simply verify no exception is thrown. Run in TestFlight builds as part of the QA pipeline.
Rive animation files may not be available at implementation time, blocking the wrapped-animation-controller from being fully tested. If asset delivery is delayed, the controller cannot be validated for memory-leak-free disposal.
Mitigation & Contingency
Mitigation: Implement the animation controller with stub/placeholder AnimationController instances first so the lifecycle and disposal logic can be unit-tested independently of Rive assets. Define a named animation registry interface early so UI components can reference animations by name without coupling to specific Rive files.
Contingency: If Rive assets are not delivered before Epic 3 begins, replace Rive animations with Flutter implicit animations (AnimatedOpacity, ScaleTransition) as a drop-in and schedule Rive integration as a follow-on task once assets arrive.
The annual_summaries Supabase RPC aggregating 12 months of activity records per mentor may exceed acceptable query latency (>2s) for mentors with high activity volumes such as the HLF mentor with 380 registrations cited in workshop notes.
Mitigation & Contingency
Mitigation: Design the RPC to materialise summary results into the annual_summaries table via a scheduled edge function rather than computing on demand. The repository reads pre-computed rows, keeping query latency constant regardless of activity volume.
Contingency: If on-demand queries are required for real-time period switching, add a PostgreSQL partial index on (mentor_id, activity_date) and implement a client-side loading skeleton so slow queries degrade gracefully rather than blocking the UI.
iOS requires photo library permission before saving a screenshot to the gallery. If the permission prompt is triggered at an unexpected point in the share flow, the UX breaks and users may deny permission permanently, making gallery save unavailable.
Mitigation & Contingency
Mitigation: Trigger the permission request only when the user explicitly chooses 'Save to gallery' in the share overlay, not on screen load. Implement a pre-prompt explanation screen following Apple HIG so users understand why the permission is needed before the system dialog appears.
Contingency: If permission is denied, gracefully fall back to clipboard copy and system share sheet options which do not require photo library access, and surface a non-blocking snackbar explaining the limitation.