[C++] Implement "list_parent_indices" vector function

[asfimport]

The return value has the same size as the child array of a List type and contains values providing the "cell index" of each child value relative to the parent list array.

For example, the list array

[ [0, 1], null, [2], [3, 4]]

would output

[0, 0, 2, 3, 3]

Note that there is no null because the child array has no nulls. If the list has null values whose offsets point to non-empty child sections then these will have to be null in the output to preserve the contract that the output array has the same length as the child array

Reporter: Wes McKinney / @wesm
Assignee: Wes McKinney / @wesm

Related issues:

• [C++] [Python] Proposal for several Array utility functions (is related to)

_{Note: This issue was originally created as ARROW-9249. Please see the migration documentation for further details.}

[asfimport]

Wes McKinney / @wesm:
Resolved in e1c3334