👌 Allow needextend to use dynamic functions

[chrisjsewell]

closes #970 (cc @arwedus)

One key change here, which I think makes sense but should be agreed on,
is that we alter the needs data post-processing order, to extend the needs, before processing dynamic values, links and constraints.

This did not break any of the tests, and I feel should not breaking any existing users, unless they are doing something very exotic 😅

[danwos]

Looks good and thanks for the work 👍

[arwedus]

should be added with the sphinx API, as in practical use cases (to avoid messing up the incremental build)

[wuhuhit]

Hi man, I see that currently we can use dynamic functions in need_extend directive. And I want to know can we use the dynammic funcitions in need_flow, need_bar, need_pie?

[danwos]

No, you can't. Mostly because I see no use case for this.
Dynamic functions are used to set meta-data of a need, what you are not doing with needflow and co.

But maybe the filter-function feature covers your use case?
https://sphinx-needs.readthedocs.io/en/latest/filter.html#filter-function

[wuhuhit]

Thanks for your repy, I want to collect the needs info during sphinx build with dynamic functions for the need_flow, need_bar, need_pie directives. You know then I can dynamic filter the directives with the specify needs id. that's quiet convenient.
As you said, I found that need-pie support filter-func and it perhaps can solve my problem, does need_flow and need_bar also support filter-func?

[danwos]

Mhh that sounds a little bit like a misuse of dynamic functions.
The need info and all data from the Sphinx-Needs directive are available in the Sphinx app/env object, so for such functions, you should register a handler for one of the Sphinx events.

But to be honest, I haven't understood your use case 100%.
Why do you need the internal data of needbar, needpie and co?

[wuhuhit]

sorry, perhaps what I said was not detaild enough.
take need_flow directive as an example, as below:
..needflow::
:filter: id in [...]
I wang to use dynamic functions or filter funcitons to fill in the special needs info here,during the sphinx build process. Then I can dynamic adjust the filter value based on the latest sphinx result. And the similar method for needbar and needpie.
Do you have some good ideas about this? many thx

[danwos]

Ok, this specific way is not supported, but filter-code/function should do the trick.
Sphinx-Jinja could also be used here and variables could be set by conf.py.

[wuhuhit]

you know, you guys has said in the filter-function discription that needpie directive support filter-code, and I want to know whether needflow and needbar also support filter function? And I plan to do some testwith filter code.
Besides, Sphinx-Jinjia seems also work, But I'm sorry I'm not very clear about the sphinx-jinjia solution. could you please provide the sphinx-jinjia solution in more detail for me? And I will also try it.
Thank you very much

[wuhuhit]

Hi Danwos, Thank you for your great suggestions.
I have tried the special directives successfully with filter-code/filter fuction.