XLSX File Generator

The workbook is built according to the format specification: a list of types, relationships, the workbook itself, and a sheet with rows. The rows contain both text and numbers, so the file is useful not only for testing uploads but also for testing parsers.

Row count and file size are set separately

Spreadsheet imports are usually limited by the number of rows, while uploads are limited by file size. These are different limits, and each one needs its own test file: a thousand-row spreadsheet weighs little, while a one-megabyte spreadsheet may turn out to be short.

Rows are written as inline values, without a separate string table. This keeps the package simpler, and it makes no difference to the loader being tested.