possible bug with ireduce compared to jq reduce

[dhx-mike-palandra]

Quoting:
< https://mikefarah.gitbook.io/yq/operators/reduce#yq-vs-jq-syntax >

Reduce syntax in yq is a little different from jq - as yq (currently) isn't as sophisticated as jq and its only supports infix notation (e.g. a + b, where the operator is in the middle of the two parameters) - where as jq uses a mix of infix notation with prefix notation (e.g. reduce a b is like writing + a b).

First, there is a minor typo above. I suggest removing the "s" in "its":

... as jq and it(s) only supports ...

When you concede in this quote that jq is more sophisticated, I'm unsure if you meant by reduce syntax only or also by implementation when compared to ireduce, so I may have found a bug here.

I'm running latest version of yq on Linux/x86_64:

yq --version
yq (https://github.com/mikefarah/yq/) version v4.53.6

The first command from each shell (bash) pipeline below is the same.

This one produces the expected output:

yq -n -ojson '"\"a\"=\"b\" \"x\"=\"y\""' | yq -pjson -ojson '[capture("\"(?<key>.*?)\"=\"(?<value>.*?)\""; "g")]'
[
  {
    "key": "a",
    "value": "b"
  },
  {
    "key": "x",
    "value": "y"
  }
]

This is consistent with jq; i.e. output is the same if yq -pjson -ojson from second command of shell pipeline is replaced with jq.

There is a difference between jq and yq when capture is expressed in terms of match and (i)reduce to construct a logically equivalent expression:

yq -n -ojson '"\"a\"=\"b\" \"x\"=\"y\""' | jq '[match("\"(?<key>.*?)\"=\"(?<value>.*?)\""; "g") | (reduce .captures[] as $capture ({}; .[$capture.name] = $capture.string))]'						      
[
  {
    "key": "a",
    "value": "b"
  },
  {
    "key": "x",
    "value": "y"
  }
]

yq -n -ojson '"\"a\"=\"b\" \"x\"=\"y\""' | yq -pjson -ojson '[match("\"(?<key>.*?)\"=\"(?<value>.*?)\""; "g") | (.captures[] as $capture ireduce ({}; .[$capture.name] = $capture.string))]'
[
  {
    "key": "x",
    "value": "y"
  }
]

jq produces expected output but yq does not.