[ARROW-4886] [Rust] Inconsistent behaviour with casting sliced primitive array to list array

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.12.0
• Fix Version/s: 0.14.0
• Component/s: Rust
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/21396
• Assignee: Neville Dipale
• Reporter: Neville Dipale
• Created: 15/Mar/19 03:37
• Updated: 11/Jan/23 07:36
• Resolved: 21/Jun/19 14:21

Description

csun I was going through the C++ cast implementation to see if I've missed anything, and I noticed that ListCastKernel (https://github.com/apache/arrow/blob/master/cpp/src/arrow/compute/kernels/cast.cc#L665) doesn't support casting non-zero-offset arrays. So I investigated what happens in Rust ARROW-4865. I found an inconsistency where inheriting the incoming array's offset could lead us to read invalid data.

I tried fixing it, but found that a buffer that I expected to be invalid was being returned as valid, but returning invalid data.

I've currently disabled casting primitive to array where the offset is not zero, and I'd like to wait for ARROW-4853 so I can see how sliced lists behave, and fix this inconsistency. That might only happen in 0.14, so I'm fine with that.

Issue Links

• is blocked by: ARROW-4853 [Rust] Array slice doesn't work on ListArray and StructArray
• is related to: ARROW-4865 [Rust] Support casting lists and primitives to lists
• links to: GitHub Pull Request #4365