[ARROW-15919] [C++] Add_kernel not commutative (timestamps & duration maths)

• Type: Sub-task
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 8.0.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/31348
• Assignee: Rok Mihevc
• Reporter: Dragoș Moldovan-Grünfeld
• Created: 11/Mar/22 16:15
• Updated: 11/Jan/23 11:40
• Resolved: 21/Mar/22 13:48

Description

A + B != B + A when it comes to adding duration to timestamp, for example.

Should add(timestamp, duration) == add(duration, timestamp)? Or, in other words, should the order matter?

This has surfaced in R when creating some of the lubridate bindings - see non-lubridate example below

a <- ymd("2009-08-03", tz = "America/Chicago")
a_array <- Array$create(rep(a, 12))

b_array <- Array$create((1:12)*86400L)$cast(time32(unit = "s")) - 
  Array$create(rep(0L, 12))$cast(time32(unit = "s"))

a_array
a_array
Array
<timestamp[us, tz=America/Chicago]>
[
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000,
  2009-08-03 05:00:00.000000
]

b_array
Array
<duration[s]>
[
  86400,
  172800,
  259200,
  345600,
  432000,
  518400,
  604800,
  691200,
  777600,
  864000,
  950400,
  1036800
]

a_array + b_array
Array
<timestamp[us, tz=America/Chicago]>
[
  2009-08-04 05:00:00.000000,
  2009-08-05 05:00:00.000000,
  2009-08-06 05:00:00.000000,
  2009-08-07 05:00:00.000000,
  2009-08-08 05:00:00.000000,
  2009-08-09 05:00:00.000000,
  2009-08-10 05:00:00.000000,
  2009-08-11 05:00:00.000000,
  2009-08-12 05:00:00.000000,
  2009-08-13 05:00:00.000000,
  2009-08-14 05:00:00.000000,
  2009-08-15 05:00:00.000000
]

b_array + a_array
 Error: NotImplemented: Function 'add_checked' has no kernel matching input types (array[duration[us]], array[timestamp[us, tz=America/Chicago]])
/Users/dragos/Documents/arrow/cpp/src/arrow/compute/function.cc:231 DispatchBest(&inputs)

Issue Links

• relates to: ARROW-11090 [C++] Support temporal arithmetic ({time,date}{32,64}, timestamp, interval)
• links to: GitHub Pull Request #12612