Write unit tests for PDF report generator
epic-bufdir-reporting-export-processing-services-task-014 — Write unit tests for the BufdirPdfGenerator verifying correct page layout structure, presence of all required Bufdir template sections, proper Norwegian date and number formatting, and that the generated PDF is a valid parseable document. Include rendering tests for edge cases such as organizations with zero activities and organizations with very large activity counts causing multi-page reports.
Acceptance Criteria
Technical Requirements
Execution Context
Tier 3 - 413 tasks
Can start after Tier 2 completes
Implementation Notes
The pdf Dart package (pub.dev/packages/pdf) builds a Document tree before serialization — this is the ideal seam for assertions. Create a PdfTestHelper class with methods like extractTextContent(Uint8List pdfBytes) that searches raw bytes for UTF-8 text strings; this avoids a full PDF parser dependency in tests. For Norwegian date formatting, assert that DateFormat('d. MMMM y', 'nb_NO').format(date) produces the expected string and that this value appears in the PDF content.
For multi-page test: generate with enough records to force page break (depends on row height), then count page occurrences of the PDF 'Page' object keyword in raw bytes. Zero-activity edge case is the highest-risk crash scenario — prioritize this test. If the generator uses Flutter widgets internally (e.g., via printing package), wrap in flutter_test's pumpWidget and capture the document via a callback rather than direct instantiation.
Testing Requirements
Unit tests using flutter_test. Since the pdf Dart package produces Document objects before serialization, test at two levels: (1) document model level — assert pages, widgets, and text content on the Document object before calling save(); (2) byte level — call save() and parse the resulting bytes to confirm validity and text presence. Use a lightweight PDF text extractor utility (or regex on raw bytes for ASCII section headers) to assert required strings exist. Test groups: happy path (10 activities), zero activities, single activity, large dataset (500 activities for multi-page), Norwegian date formatting, Norwegian number formatting.
Mock any external font loading with in-memory font bytes to keep tests hermetic.
NHF contacts can belong to up to five local chapters simultaneously. If the deduplication logic in the activity query service incorrectly attributes cross-chapter activities, organisations will either under-report or over-report to Bufdir, which could trigger grant clawback or compliance investigations.
Mitigation & Contingency
Mitigation: Implement deduplication using the existing multi-chapter membership service as the source of truth for chapter affiliation. Write test fixtures covering all known multi-chapter edge cases and validate outputs against manually prepared reference exports from NHF.
Contingency: If deduplication cannot be made deterministic for complex hierarchies before release, gate the export behind an org-level feature flag and require NHF to validate a preview export against their manual Excel before enabling in production.
Server-side Dart libraries for Excel generation are less mature than equivalents in Node.js or Python. The chosen library may lack support for Bufdir-required formatting features (merged cells, data validation, specific date formats), requiring significant workaround effort or a library switch mid-implementation.
Mitigation & Contingency
Mitigation: Evaluate the top two Dart xlsx libraries (excel, spreadsheet_decoder) against a Bufdir template sample file before committing. Identify all required formatting features and verify library support in a spike.
Contingency: If no Dart library meets requirements, implement the Excel generation as a Supabase Edge Function in TypeScript using the well-supported ExcelJS library, exposing it to the Dart backend via an internal RPC call.
The attachment bundler must retrieve documents from Supabase Storage that were uploaded by the document attachments feature. If storage paths, RLS policies, or signed URL expiry have not been standardised across features, the bundler may fail to retrieve attachments at export time.
Mitigation & Contingency
Mitigation: Audit the document attachments feature's storage schema and RLS policies before implementing the bundler. Agree on a stable internal service-account access pattern for cross-feature storage reads.
Contingency: If cross-feature storage access cannot be made reliable, implement the bundler to include only attachments that can be retrieved successfully and produce a manifest listing any attachments that could not be bundled, rather than failing the entire export.