Script to catch unnecessary style elements

Question

Script to catch unnecessary style elements

kylebarron opened this issue 5 years ago · comments

There are several style elements, like visibility: visible that are unnecessary because those are the same as the defaults. It seems advantageous and not very difficult to write a short JS script to test PRs for these elements. (It could also be added to the pre-commit hook).

My thinking is to simply traverse the JSON and check each element of each style rule against that rule's default value. So the first step I suppose is to construct a list of the style defaults.

Björn · Answer 1 · Wed Jan 22 2020 03:51:00 GMT+0800 (China Standard Time)

The style defaults should all be available here:
https://raw.githubusercontent.com/mapbox/mapbox-gl-js/master/src/style-spec/reference/v8.json

e.g. https://github.com/mapbox/mapbox-gl-js/blob/master/src/style-spec/reference/v8.json#L673

Orange Mug · Answer 2 · Wed Jan 22 2020 03:57:54 GMT+0800 (China Standard Time)

If it was built as a standalone lib, and exports the following definition, we could run it when opening a style in maputnik also (I guess we'd probably want to prompt the user also)

export default function (style, styleSpec) {
    // pruning code...
    return newStyle;
}

Kyle Barron · Answer 3 · Wed Jan 22 2020 05:12:19 GMT+0800 (China Standard Time)

Oh good idea, I was thinking only of validating an existing style, but pruning it and returning the minimal style would be good too.

Kyle Barron · Answer 4 · Wed Jan 22 2020 06:58:45 GMT+0800 (China Standard Time)

Ok I have a basic example here:
https://github.com/kylebarron/mapbox-gl-style-prune

My JS isn't great yet, so it can absolutely be improved, but it's a start that works on my osm-liberty-topo style, which is included in the repo for testing.

It checks all paint and layout properties on the style against the default property on the style spec's object.

Kyle Barron · Answer 5 · Wed Jan 22 2020 06:59:00 GMT+0800 (China Standard Time)

Also I'd be happy to move it to @maputnik if you want

Orange Mug · Answer 6 · Thu Jan 23 2020 17:00:46 GMT+0800 (China Standard Time)

My JS isn't great yet

It looks good to me @kylebarron

Also I'd be happy to move it to @maputnik if you want

Thanks, I think that would be good, however let's hold off on that until we have it as a part of the Maputnik codebase somewhere. My preference to adding repos to the Maputnik org is, hold off adding them until they become a little more mature/used/tested. I think it'll keep the organisation tidy in the long run.

Björn · Answer 7 · Thu Jan 23 2020 17:58:13 GMT+0800 (China Standard Time)

@kylebarron 👍

Regarding:

we could run it when opening a style in maputnik also (I guess we'd probably want to prompt the user also)

I also think it would be good to integrate this in Maputnik somehow, but I'm not sure if this should run when opening a style:

Playing around with a style and trying different setting in Maputnik could add some default values to the style (see e.g. #71 (comment)). So there should also be an option to run the script when exporting a style.
If the script runs when opening a style, we should prompt the user because the style could be modified (as @orangemug mentioned). I like how easy and fast it is currently to open a style in Maputnik. Such a prompt would need action from the user because there should be a choice, so the opening of the style would not be as easy and fast as before.

What about adding a checkbox "Prune style" to the export modal (which is checked by default) and do nothing when opening a style?

The current export modal:

Kyle Barron · Answer 8 · Thu Jan 23 2020 23:26:56 GMT+0800 (China Standard Time)

I need to figure out how to expose it as a CLI, and also need to figure out what framework to use for basic tests.

I like @pathmapper's suggestions of it not running it when opening a style but with the option of running it when exporting it.