yqi | retain newlines & list indentation with `yq e -i`

yqi.sh

get_yamlfmt_config() {
  # $1 == file
  cat <<EOF
formatter:
  indentless_arrays: $(
    first_list=$(grep -m 1 -B 1 '^ .* -' $1)
    # If the first entry whitespace is not in (or is larger than) the list name whitespace - it's indented.
    if ! grep -q "$(tail -n 1 <<<"$first_list" | cut -d'-' -f 1)" <<<"$(head -n 1 <<<"$first_list")"; then
      echo "false"
    else
      echo "true"
    fi
  )
  retain_line_breaks_single: true
  trim_trailing_whitespace: true
EOF
}

yqi() {
  # $1 == expression | $2 == file
  # Must get yamlfmt conf pre-edit
  conf=$(get_yamlfmt_config $2)
  # Replace empty lines with placeholder comment -> update -> diff -> patch
  file=$(sed 's/^$/# line/' $2 | yq eval $1 | diff -B $2 - | patch $2 -o -)
  # Patching prints - remove that line and delete placeholder comments
  echo -e "$(grep -v '^patching' <<<${file} | sed 's/^# line$//g')" >$2
  # Format in place using initial fmt config
  yamlfmt -conf <(echo -e $conf) $2
}

# Ensure `yamlfmt` - can remove / comment out after first use or running directly
command -v yamlfmt &>/dev/null || go install github.com/google/yamlfmt/cmd/yamlfmt@latest

# Uncomment if you just want to throw this in your PATH (e.g., download to ~/.local/bin/yqi)
# and run it directly as opposed to adding to your shell's rc file.
# yqi "$1" "$2"