JSON Formatting in mvn plugin

[blacelle]

The maven plugin seems not to support JSON formatting. Is there a good reason for this? Or would it be considered a good contribution from a new-comer ?

[nedtwigg]

There is no reason for it, and it would be a great contribution from a newcomer!

• https://github.com/diffplug/spotless#why-are-there-empty-squares
• https://github.com/diffplug/spotless/blob/main/CONTRIBUTING.md

[blacelle]

A PR is open. I see this will not fulfil my own need ('\t' as tabulation). Ecryd sortPom accepts -1 spaces to trigger tabulation indentation (https://github.com/Ekryd/sortpom/wiki/Parameters#for-both-the-sort-and-verify-goal). Is it OK I open another PR to accept such a parameter in com.diffplug.spotless.json.gson.GsonStep.State.generateIndent(int)?

[nedtwigg]

Thanks for the PR

If the only problem is indenting with tabs vs space, I would recommend the indentWithTabs step instead of adding a feature/mode to an existing step. If it's a small amount of new code I'd be okay to merge another PR, but if it's a lot of code I'd rather point people to indentWithTabs.

[blacelle]

Thanks @nedtwigg. The existing PR does not hold anything relating to tabs.

Being new to Spotless, it took few a few seconds to understand your point. My suggested changes (-1 for tabulation) would be very minimal. I agree it is awkward, still it is the way some plugin works (e.g. Ecryd SortPom, then some formatting-plugins users are used to it (at the very least myself,, which is of course veryopinionated xD)).

I see the gradlePlugin enables Prettier and other external formatters to enable JSON formatting. However, it seems more difficult to reach with maven. Could you provide a snippet of the mvn pom.xml <configuration /> section how you would recommend reaching tabs in json formatting? (If it is an existing feature, I could open a dedicated ticket, else it would help me understand how to best implement this feature.)

[nedtwigg]

I am terrible at maven, I just merge things that

• people actually want for themselves
• doesn't break and has tests so it stays not broken
• won't be hard for the Spotless team to maintain into the future

So whatever -1 flags you want to add are okay with me, but I still think this existing feature is easier to use and definitely easier to build (already done!)

        <indent>
          <tabs>true</tabs>
          <spacesPerTab>4</spacesPerTab>
        </indent>

[blacelle]

@nedtwigg I now better understand your point. Something unclear to me was how <formats> and <json> would interleave themselves. I suppose formats are applied after specialized formatters (as mvn is much less expressive in term of ordering/customization than gradle), in which case tab indentation is already feasible.

The PR for JSON formatting in mvn is ready.

I open another issue which may describe an issue related to interleaving formats and specialized formatters (#1455)

[nedtwigg]

Published in plugin-maven 2.30.0, thanks for the great PR @blacelle.