Write widget tests for FeatureGate widget
epic-organization-feature-flags-ui-task-008 — Write comprehensive Flutter widget tests for the FeatureGate widget covering: renders child when flag is enabled, renders fallback when flag is disabled, renders fallback when flag is loading, renders nothing when no fallback provided and flag is disabled, reacts to provider state changes, and handles unknown flag keys without crashing. Use flutter_test and mock Riverpod providers.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 2 - 518 tasks
Can start after Tier 1 completes
Implementation Notes
Use ProviderContainer or ProviderScope.overrides with a manual StateProvider
Document each test case with a short // given / when / then comment block for readability.
Testing Requirements
This task IS the testing deliverable. All 8+ test cases listed in acceptance criteria must be implemented. Use group() blocks to organize by scenario. Each test must: pump a ProviderScope with an overridden featureFlagProvider returning the desired AsyncValue state, pump the FeatureGate widget with child and optional fallback, and assert find.text('child') or find.text('fallback') with findsOneWidget/findsNothing.
State-change tests must update the provider state mid-test using a StateController or by replacing the override and calling tester.pumpAndSettle(). Achieve 100% branch coverage on FeatureGate's build method.
The feature flag admin screen allows persisting changes to organization_configs. If the role guard is implemented only client-side (checking role state in Riverpod), a user who manipulates their local role state could toggle flags for their organization without proper server-side authorization, potentially exposing features prematurely.
Mitigation & Contingency
Mitigation: Implement server-side authorization for flag update operations using Supabase RLS UPDATE policies that check the user's role in the memberships table. The client-side guard is UX only; the database enforces the actual restriction.
Contingency: If an unauthorized update is detected, audit the RLS policies and add a Supabase Edge Function as an authorization middleware for flag toggle operations, rejecting requests from non-admin role JWTs.
Developers on other feature teams may use FeatureGate incorrectly — for example, wrapping business logic rather than UI, or using it before flag initialization completes — leading to features that are visible but non-functional or cause runtime errors when flags are queried in a loading state.
Mitigation & Contingency
Mitigation: Add assert statements in FeatureGate's build method that throw in debug mode if the provider is still in a loading state. Write developer documentation with a clear usage contract: FeatureGate is UI-only; logic gating must use the provider's isEnabled method directly. Include lint examples in the codebase.
Contingency: If misuse is found in code reviews, add a custom Dart lint rule via custom_lint that flags FeatureGate usage outside of the widget tree, and conduct a codebase audit to find existing violations.
If the audit log is stored in the same organization_configs table without pagination or archival strategy, high-frequency flag changes during pilot testing could produce an unbounded number of rows, degrading query performance on the admin screen.
Mitigation & Contingency
Mitigation: Store audit log entries in a separate feature_flag_audit_log table with an index on (organization_id, changed_at DESC). Implement cursor-based pagination in the repository and limit the initial load to 50 entries.
Contingency: If table size becomes a performance concern, add a Supabase scheduled function to archive entries older than 90 days to cold storage, and add a database index on changed_at for range queries.