Widget and Integration Tests for Export UI
epic-bufdir-reporting-export-ui-task-013 — Write flutter_test widget tests covering: period selector preset and custom-range selection, format selector state transitions, confirmation dialog rendering with correct data, progress indicator states, export history list item rendering, pagination, and re-download tap handling. Achieve ≥80% line coverage on all five components. Include golden tests for key layouts.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 7 - 84 tasks
Can start after Tier 6 completes
Implementation Notes
Structure test files mirroring the source: one test file per widget. Use `blocTest` from bloc_test for BLoC event/state verification and `pumpWidget` with a `MaterialApp` wrapper for widget tests. For the pagination test, use a ScrollController and programmatically scroll to the bottom rather than relying on real scroll physics. Golden tests must be generated on a Linux CI runner to avoid platform font differences — document this in a test README.
For expired-URL tests, mock the repository to return an `ExportHistoryItem` with `isExpired: true` and assert that the re-download button shows a 'Link expired' tooltip rather than triggering download. Ensure all BLoC streams are closed in `tearDown` to prevent test pollution.
Testing Requirements
Use flutter_test with MockBloc/MockCubit (bloc_test package) to inject controlled states into each widget under test. Write pumpWidget wrappers that provide the required BLoC/Riverpod providers. Cover happy path, empty state, error state, and boundary conditions for every widget. Use goldentest package (golden_toolkit or alchemist) pinned to a specific Flutter version for reproducible golden files.
Run coverage with `flutter test --coverage` and enforce ≥80% line coverage via a CI lcov threshold check. All tests must be deterministic — avoid real timers; use fake_async or clock overrides.
For large exports that run for 10–30 seconds, a static loading spinner will feel broken to users on slow mobile connections. If the UI cannot display meaningful progress during the export pipeline, coordinators may abandon the flow or trigger duplicate exports by pressing the button multiple times.
Mitigation & Contingency
Mitigation: Implement streaming progress events from the orchestrator BLoC through named pipeline stages (querying, mapping, generating, uploading). Display each stage label with a progress indicator on the trigger screen. Disable the generate button immediately on first tap to prevent duplicates.
Contingency: If streaming pipeline progress is not feasible in the first release, implement a deterministic stage-based progress animation (10% querying, 50% generating, 90% uploading) that gives users feedback without requiring real server events.
Custom date range pickers are among the most common accessibility failures in mobile apps. Blindeforbundet users rely on VoiceOver, and NHF users include people with cognitive impairments. A non-accessible period picker could make the entire export workflow unusable for a significant portion of the intended user base.
Mitigation & Contingency
Mitigation: Build the period picker using Flutter's native date picker semantics as the foundation, with preset shortcuts as primary navigation (reducing the need to interact with the custom range picker at all). Test with VoiceOver on iOS and TalkBack on Android before UI epic sign-off. Engage Blindeforbundet's test contact for accessibility validation.
Contingency: If the custom date range picker cannot be made fully accessible before release, ship only the preset period shortcuts (covering the majority of use cases) and add the custom range picker in a follow-up sprint after dedicated accessibility remediation.