Variables are mixed up

[ffried]

Describe the bug
Variables seem to be mixed up when using within a map.

Version of yq: 4.30.5
Operating system: mac
Installed via: homebrew

Input Yaml
Concise yaml document(s) (as simple as possible to show the bug, please keep it to 10 lines or less)
input.yml:

key1:
  - value1A
  - value1B
  - value1C

key2:
  - value2A
  - value2B
  - value2C

Command
The command you ran:

yq e '. as $root | keys | map(select(. == "key1" or . == "key2") | . as $kind | $root[$kind] | map({"combination": ($kind + "/" + .)})) | flatten' input.yml

Actual behavior

- combination: key1/value1A
- combination: key2/value1A
- combination: key1/value1B
- combination: key2/value1B
- combination: key1/value1C
- combination: key2/value1C
- combination: key1/value2A
- combination: key2/value2A
- combination: key1/value2B
- combination: key2/value2B
- combination: key1/value2C
- combination: key2/value2C

Expected behavior

- combination: key1/value1A
- combination: key1/value1B
- combination: key1/value1C
- combination: key2/value2A
- combination: key2/value2B
- combination: key2/value2C

Additional context

I'm aware the the expression isn't fully optimized (e.g. pick could be used). But the very same expression works in jq:

yq -o=json input.yml | jq '. as $root | keys | map(select(. == "key1" or . == "key2") | . as $kind | $root[$kind] | map({"combination": ($kind + "/" + .)})) | flatten' -

results in:

[
  {
    "combination": "key1/value1A"
  },
  {
    "combination": "key1/value1B"
  },
  {
    "combination": "key1/value1C"
  },
  {
    "combination": "key2/value2A"
  },
  {
    "combination": "key2/value2B"
  },
  {
    "combination": "key2/value2C"
  }
]

which is the equivalent to the expected yaml.

[mikefarah]

Thanks for the detailed bug description, this will be fixed in the next release along with #1566

[mikefarah]

Fixed in v4.31.2