[Bug]: WithMapping does not provide index and / or rowOffset

[boxsnake]

Is the bug applicable and reproducable to the latest version of the package and hasn't it been reported before?

• Yes, it's still reproducable

What version of Laravel Excel are you using?

3.1.62

What version of Laravel are you using?

11.36.1

What version of PHP are you using?

8.3.17

Describe your issue

In my case, I am going to generate a worksheet with following situations:

• each data row mapped to 4 sheet rows
• a formula is in the rows

Hope rowIndex or rowOffset (excel row number) can be passed to map so that it can be easier in such case.

How can the issue be reproduced?

<?php
class DemoExport implements WithMapping, FromCollection
{
    protected Collection $rows;

    public function __construct(
        Collection $rows
    ) {
        $this->rows = $rows;
    }

    public function map($row): array
    {
        // In my case, I cast a `index` field to my data
        // However, it is not so elegent to inject a new field only for render
        $formula = sprintf('=F%u*G%u', $row->index * 4, $row->index * 4 + 3);
        return [
          [
            // Row 1
          ],
          [
            // Row 2
          ],
          [
            // Row 3
          ],
          [
            // Row 4
            $formula
          ]
        ];
    }
}

What should be the expected behaviour?

<?php
class DemoExport implements WithMapping, FromCollection
{
    protected Collection $rows;

    public function __construct(
        Collection $rows
    ) {
        $this->rows = $rows;
    }

    public function map($row, $index): array
    {
        $formula = sprintf('=F%u*G%u', $index * 4, $index * 4 + 3);
        return [
          [
            // Row 1
          ],
          [
            // Row 2
          ],
          [
            // Row 3
          ],
          [
            // Row 4
            $formula
          ]
        ];
    }
}

or

<?php
class DemoExport implements WithMapping, FromCollection
{
    protected Collection $rows;

    public function __construct(
        Collection $rows
    ) {
        $this->rows = $rows;
    }

    public function map($row, $index): array
    {
        // `$startRow` is where this map started
        $formula = sprintf('=F%u*G%u', $startRow, $startRow + 3);
        return [
          [
            // Row 1
          ],
          [
            // Row 2
          ],
          [
            // Row 3
          ],
          [
            // Row 4
            $formula
          ]
        ];
    }
}

[patrickbrouwers]

If you use collection you can call the map on the collection itself and not use the withmapping concern.