`import_sources` carried only the mechanical CSV settings. The two fields that
decide how an amount is READ -- `amount_mode` and `sign_convention` -- lived
only on `import_config_templates`. That asymmetry is the root bug of this
chantier: restoring a saved source re-inferred the mode from the mapping and
hardcoded `signConvention: "negative_expense"` (useImportWizard.ts:321-323), so
a source configured with positive expenses silently flipped back on its second
import. After v17 both tables carry the same eight format fields.
v17 is strictly additive -- v1 to v16 are untouched, and the diff is pure
insertion. The four columns are defaulted or nullable so the ALTERs are safe on
a populated database:
- amount_mode / sign_convention carry a CHECK, same pattern as v15 on
balance_accounts.kind. amount_mode admits 'absolute_indicator' from the start
so the third amount mode ships without another migration, while the database
still refuses a corrupted value today.
- header_signature stores the normalized header labels seen at the last
successful import, for drift detection.
- template_id is a provenance tag only, never re-read as format: the eight
source columns are authoritative, so editing a template changes no linked
source. ON DELETE SET NULL keeps the source and its format when a template
goes.
The backfill reproduces exactly the rule the wizard applied on the fly, so no
source changes behaviour on migration. It tests `column_mapping LIKE
'%debitAmount%'` rather than json_extract, so the migration depends on no JSON1
extension in the bundled SQLite. sign_convention is deliberately not
backfilled: its DEFAULT restores precisely the value the code hardcoded, the
only past convention that can be inferred.
The four columns are mirrored into consolidated_schema.sql. They are inert
there on the production path -- that script runs after every migration and only
uses CREATE TABLE IF NOT EXISTS, so new profiles receive them from v17 -- but
it stays the tested reference definition, and a parity test now compares it
against the v1->v17 chain column by column, DEFAULT by DEFAULT, CHECK by CHECK
and FK by FK. Both halves of that test were mutation-checked to confirm they
fail on drift.
5 new tests (111 Rust total): v17 on a populated v16 database with a child row,
the backfill against 5 mapping shapes, the CHECKs, the provenance-tag
semantics, and the consolidated parity.
Resolves#323
