The root bug of this chantier. `import_sources` carried no `amount_mode` and no
`sign_convention` until v17, so restoring a configured source re-inferred the
mode from `mapping.debitAmount !== undefined` and wrote
`signConvention: "negative_expense"` outright (useImportWizard.ts:321-323). A
credit-card statement configured for positive expenses came back on the default
convention at its second import and `parseFilesInternal` negated every amount:
expenses landed as income, with no error shown anywhere. The format is a read
value now, not a guessed one.
Two types and a codec, not one composed type. The four carriers are
structurally incompatible -- `ImportSource.has_header` is declared boolean,
`ImportConfigTemplate.has_header` is a number, `SourceConfig` is camelCase on a
parsed mapping -- so the guarantee cannot come from a shared shape. It comes
from `src/utils/importFormat.ts` being the single conversion point between
`ImportFormatRow` (persisted: snake_case, mapping as JSON, `has_header`
normalized to 0/1) and `ImportFormat` (domain), and from its completeness test.
That test is enforced on two levels, and both were mutation-checked:
`FORMAT_FIELD_PAIRS` is typed `Record<keyof ImportFormat, keyof
ImportFormatRow>`, so a field added to the format fails to BUILD until it is
listed; the test then compares each codec's real output keys against that table,
so a field listed but not wired fails the TEST. Dropping `sign_convention` from
`formatToRow` -- the shape of the original bug -- fails 14 tests.
`formatFromRow` validates rather than falls back. The v17 CHECK admits
`absolute_indicator` so the third amount mode ships without another migration,
but the app cannot map one: falling through to the `single` branch would read
the wrong column for every row, and anything other than `positive_expense`
would silently mean `negative_expense`. It raises an `ImportFormatError`
carrying an i18n key, and the wizard opens on a fresh configuration so
"reconfigure this source" stays an action the user can actually take.
Also here:
- The config write moves from `checkDuplicatesInternal` to `executeImport`, so
an import abandoned at the duplicate step leaves no configuration behind. It
is the only write point in the hook and a guard test holds that.
- Switching amount mode prunes the abandoned mode's columns, so the mode owns
the mapping rather than the reverse. The column the `<select>` merely displays
is deliberately not materialized -- #325 turns an unmapped amount column into
an explicit row error, and writing a 0 here would make it unreachable. The
mode and the pruned mapping land in ONE state update: the panel's handlers
each spread the same `config` prop, so two calls would see the same stale
value.
- `template_id` is recorded and restored as provenance only, never re-read as
format. `selectedTemplateId` is no longer blanked on every source selection.
An acceptance test rewrites a template end to end and asserts the linked
source reads identically, plus a non-vacuity check that the template really
changed.
- Both template writers go through the codec too, so a new format field cannot
reach one table and miss the other.
`parseFilesInternal` is untouched: link 1's static guard on its five pinned
expressions still passes. 39 new tests (963 vitest total, was 924), build clean,
`cargo check` clean, no migration.
Resolves#324
