feat: Add jq template function

[twpayne]

Refs #2826.

[halostatue]

I’m getting an unexpected [] wrapping the output:

$ go run . execute-template '{{ dict "hello" 1  | jq "." | toJson }}'
[{"hello":1}]
$ go run . execute-template '{{ 1  | jq "." | toJson }}'
[1]⏎

EDIT: Having read the documentation, I see that’s expected. It doesn’t feel quite right to me.

[halostatue]

This is going to lead to very hard to read template functions:

op document list --format json |
  go run . execute-template --with-stdin \
    '{{ .chezmoi.stdin | fromJson | jq ". | map(select(.title | startswith(\"aws-credentials: \")) | { (.title): .id }) | add" | first | toJson }}'

I’m also not sure how I would embed dynamic variables given the overloading of . and the fact that the JQ source string isn’t a template itself.

I don’t think this is a bad addition, but I don’t know how useful it will be.

[halostatue]

I think that this will be more useful if we approach the jq source file as . | jq (includeTemplate "…" (data)). There’s no need for any additional functions (I was going to suggest jqFile, but that probably isn’t necessary with include and includeTemplate).

[halostatue]

We should be on the lookout for more complex examples to demonstrate, because the value of jq here will be in the flexibility provided.

[twpayne]

I don’t think this is a bad addition, but I don’t know how useful it will be.

That's a very fair point. I'll close this PR for now. We can re-open it if it turns out that there's a good use for this functionality.

[twpayne]

Re-opening as @halostatue identified a possible use case in #2864 (reply in thread).

Another use case is a replacement for some of the password manager functions like onepasswordDetailsFields and bitwardenFields. In short, the jq template function allows extraction of specific data from complex structures in a succinct way.

[halostatue]

It would be nice to have this be able to call out to jq instead of using gojq if desired (similar to opting into the built-in age, but instead opting into the use of the jq binary).

This might be better done as a future PR.