[Feature Request] Add SortDirection parameter to custom SortingFn

[rpiaggio]

We have cases where we want certain values to always be sorted at the end despite of sort direction.

This can be achieved by passing the column sort direction to a custom sorting function, where we can treat this case.

Eg, have SortingFn's signature be:

export type SortingFn<TData extends AnyData> = {
  (rowA: Row<TData>, rowB: Row<TData>, columnId: string, direction: SortDirection): number
}

It seems this could help other users too (#3300).

Thank you!

[jodoox]

@tannerlinsley Huge fan of your libraries, thanks for all these contributions.

Having undefined values at the bottom of the list regardless of the direction is a reasonable need, yet I believe it is not possible to achieve it easily with the custom sorting functions as of now. Exposing the sort direction seems like a simple yet useful addition that would solve this issue, would you be open to a PR for this?

[artchen-db]

Thanks! This approach of passing a ref to the table model works great in our use case too.

[rpiaggio]

A couple of month ago #5486 was merged, which allows undefined values to always be pulled first or last when sorting, regardless of direction.

[marceloverdijk]

@rpiaggio but this sortUndefined: last option does not support null values unfortunately.

[marceloverdijk]

I'm doing something like this now:

export const nullAwareNumber: SortingFn<any> = (a, b, columnId) => {
  const col = a.getAllCells().find(c => c.column.id === columnId)?.column
  const nullsLast = col?.columnDef.meta?.nullsLast ?? false

  const x = a.getValue<number | null>(columnId)
  const y = b.getValue<number | null>(columnId)

  if (x == null && y == null) return 0
  if (nullsLast) {
    if (x == null) return 1
    if (y == null) return -1
  } else {
    if (x == null) return -1
    if (y == null) return 1
  }
  return (x ?? 0) - (y ?? 0)
}

but I have to "find".the column for each row this way, not sure if this will give a noticeable performance penalty with large datasets...

[marceloverdijk]

and now I'm doing this everywhere:

columnHelper.accessor(
        row => row.someColumnWithNullValues ?? undefined,
        {
          id: 'someColumn',
          header: 'Header',
          sortDescFirst: true,
          sortUndefined: 'last',
        },
      ),

[artchen-db]

I was reading some old issues like #2371, it seems the direction was part of the function signature. It would be great if we could bring it back.

[sullyslegacy]

The sortEntry has id and desc however only id is being passed to the sortingFn. It would be very helpful if desc was passed in as well.

However a workaround would be doing something like
`
sortingFn: (obj1: Row, obj2: Row, prop: string) =>
sortUndefinedAtBottom(
customValueFunction(obj1.original),
customValueFunction(obj2.original),
isColumnSortedDesc(obj1, prop)
),

const isColumnSortedDesc = <T,>(column: Row, prop: string) => {
const sort = column._getAllCellsByColumnId()[prop].column.getIsSorted();
return sort === ('desc' as SortDirection);
};

const sortUndefinedAtBottom = (value1: number | undefined, value2: number | undefined, isSortedDesc: boolean) => {
if (value1 === value2) {
return 0;
}

if (value1 === undefined) {
    return isSortedDesc ? -1 : 1;
} else if (value2 === undefined) {
    return isSortedDesc ? 1 : -1;
}

return value1 - value2;

};
`

[inomn]

Hi! In case you want to sort columns with range values, for example [241, 567], and for ascending I would like to compare rows by 1st value (241), but for descending by last (567).

It is not possible to write a custom sorting function to achieve that without having sortDirection.
I would appreciate adding sortDirection to sortingFn signature.

[shahbazshueb]

Hi. I need a specific value to be sorted at the end so really need this feature.
+1 On this. Would really appreciate if sortingFn is added to sortDirection.

[ippeiukai]

Just wanted to note related issues and discussions on sortingFn vs direction topic:

• issues
  • feat: new sortUndefined last and first options #5486
  • Custom sortingFn not being run when row key is undefined #5653
  • sortUndefined and Excel like sorting #6061
• discussions
  • Force null or empty values to bottom when sorting? #2371
  • Custom sort so that a certain value is always at the end #3300
  • Possible to add SortDirection as an optional parameter to SortingFn? #5453

[ippeiukai]

Also noting that react-table v7 did have desc as the 4th param of SortingFn:
https://react-table-v7-docs.netlify.app/docs/api/usesortby#column-options

sortType: String | Function(rowA: <Row>, rowB: <Row>, columnId: String, desc: Bool)