Fix company cards import crash by transposing spreadsheet data densely

[yusufdeveloper2903]

Explanation of Change

setSpreadsheetData transposed the uploaded spreadsheet with firstRow.map(...). XLSX.utils.sheet_to_json(worksheet, {header: 1}) returns rows as sparse arrays — a blank column is left as an array hole, not undefined — and Array.prototype.map skips holes and re-emits them. So a blank column in the header row produced a hole in IMPORTED_SPREADSHEET.data.

The company cards import iterates every column with for...of, which yields undefined for a hole (unlike map), then calls column.at(rowIndex). The existing ?? '' guards the result of .at(), not the receiver, so it threw TypeError: Cannot read properties of undefined (reading 'at'). Since importTransactions is async and passed straight to onPress, it surfaced as the reported unhandled rejection.

Fixed at the single producer by building the transpose densely with Array.from({length: numColumns}, ...), so IMPORTED_SPREADSHEET.data always honors its declared rectangular string[][] type. numColumns is firstRow.length, which already counts holes, so for any dense (normal) file the output is identical — only the previously-missing column changes, becoming a real column of empty strings.

This also fixes a second symptom: the mapping UI renders columns with spreadsheetColumns.map(...), which skipped the hole, so users saw N-1 columns while columnNames was generated from data.length (N) — the UI and the column role map were out of sync. Every import flow (company cards, tags, categories, per diem, members) reads this same data, so fixing the producer removes the latent hole risk from all of them without touching any consumer.

Added tests/unit/ImportSpreadsheetTest.ts as a regression test — 3 of its 6 cases fail without this change.

Fixed Issues

$ #97101
PROPOSAL: #97101 (comment)

Tests

1. Create a CSV file named blank-column.csv with a blank second column (note the two commas):

   Card number,,Date,Merchant,Amount,Currency
   4111111111111111,,2026-07-21,Starbucks,10.00,USD
   4111111111111111,,2026-07-22,Amazon,24.50,USD
   

2. Open a Control workspace → Company cards → Add cards
3. Select a country → Next → choose Import transactions from file → Next
4. Enter any card feed layout name → Next → Choose file → upload blank-column.csv
5. On the mapping screen, verify 6 columns are listed — the blank one appears with no header and the Ignore role (before this fix only 5 were shown and the blank one was silently dropped)
6. Verify the other columns are auto-mapped to Card number / Date / Merchant / Amount / Currency
7. Press Import
8. Verify the "Import successful" modal appears and no error is logged in the JS console (before this fix, pressing Import threw TypeError: Cannot read properties of undefined (reading 'at') and nothing was imported)
9. Regression: repeat steps 2–7 with a normal CSV that has no blank column and verify the mapping screen and import behave exactly as before
10. Regression: go to Tags (or Categories) → Import spreadsheet, upload a normal CSV and verify mapping and import still work

• Verify that no errors appear in the JS console

Offline tests

1. Go offline
2. Follow steps 1–6 of the Tests section — the file is parsed locally, so verify the mapping screen still renders all columns including the blank one
3. Verify the Import button is disabled while offline
4. Go back online and verify the Import button becomes enabled and completes successfully

QA Steps

Same as tests.

• Verify that no errors appear in the JS console

PR Author Checklist

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Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

iOS: mWeb Safari

MacOS: Chrome / Safari

After fix:

REC-20260731191024.mp4

[melvin-bot]

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