Fix(table): Add table footer support

[star-szr]

Suggested merge commit message (convention)

Fix(table, html-support, source-editing, style): Add support for table footers (<tfoot>). Closes #12952.

MINOR BREAKING CHANGE (table): Conversion helper downcastTableElement() now requires TableUtils as the last argument.

MINOR BREAKING CHANGE (table): tableHeadingsRefreshHandler() now requires TableUtils as the last argument.

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Additional information

Example <tfoot> markup: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/tfoot

Maybe this is more of a feature than a fix, but at the same time this is just standard HTML support.

• Still TODO:
  • Add/update manual tests
  • Search through documentation for potential updates
  • Other? It's my first contribution so please let me know if I'm missing anything!

I have intentionally not tried to build any UI around managing table footers at this point, and have not added a SetFooterRowCommand. In my opinion, this proposed set of changes can go in (after review of course) and more UI functionality can be added later.

In addition, I have not tried to add configurable default footer rows to match the "default table headers" feature. The scope already seemed big enough without adding that, and I think it can be added later (I'm not sure there is much use case anyway).

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Credits

This work was sponsored by @ongov.

[star-szr]

Working on resolving the conflicts.

[star-szr]

I found one test case in packages/ckeditor5-table/tests/tableclipboard-paste.js that needs to be updated, working on that.

Update: Done.

[Witoso]

We will try to take a look at this soon!

[star-szr]

Just want to note that the current code assumes that all children of tfoot > tr should be th, which is probably a fair assumption for cells inside thead > tr, but less so for cells inside the footer.

I will be taking a look at this soon and likely updating so that only cells in a footer row that are also in a header column are output as th, others will be td.

[star-szr]

Updated to make table footer cells downcast to td unless they are in a header column, and made some other touch-ups that I noticed.

Edit: I'm still reviewing the whole PR to see if there are other pieces that need to be updated to reflect the th to td change. I will post a comment once I think it's ready for review again.

[star-szr]

I've reviewed everything again, and updated the logic inside tableHeadingsRefreshHandler() and added test coverage for that. I also rebased on top of master.

This is ready again for review and feedback.

[star-szr]

@Witoso please let me know if there's anything else I can do at this point.

[Witoso]

Hey, sorry for keeping this open for so long. I need to carve out some time in the team to take a look at this, and we are in the middle of some complex topics. CC @arkflpc to discuss the best time.

[tonprince]

Any updates about support of tfoot in ckeditor?

[artemdotsenko]

Any updates about support of tfoot in ckeditor?

Same question 👀

[star-szr]

To folks who are commenting checking on this, I appreciate you, and also I highly recommend that you click the thumbs up reaction in the original comment here.

[Witoso]

Sorry for keeping this open for so long 🙏 . We are battling some end-of-the-year priorities. I hope we will be able to take this to our sprint really soon.

[Megafry]

Any updates about when we can expect this to be merged in to master?

[Witoso]

We have a plan to work and merge together a few larger tables changes, but we don't have yet clear timeline yet.