Add index to legendItem interface

[LeeLenaleee]

resolves #10319

[github-actions]

Size Change: +73 B (0%)

Total Size: 257 kB

Filename	Size	Change
dist/chart.esm.js	74.3 kB	+31 B (0%)
dist/chart.js	94 kB	+29 B (0%)
dist/chart.min.js	66.8 kB	+13 B (0%)

ℹ️ View Unchanged

Filename	Size
dist/chunks/helpers.segment.js	21 kB
dist/helpers.esm.js	1.23 kB

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[LeeLenaleee]

I just noticed that I worked within the chart.js repo itself. I'm sorry.

Used that when using the web editor it would automatically create a branch in my fork since I had no rights to do it within the normal repo.

I will take more care next time that the changes are made withing my fork of the project so this does not happen again, sorry.

[kurkle]

I just noticed that I worked within the chart.js repo itself. I'm sorry.

Used that when using the web editor it would automatically create a branch in my fork since I had no rights to do it within the normal repo.

I will take more care next time that the changes are made withing my fork of the project so this does not happen again, sorry.

It's ok, just remove the branches after merge to keep it clean..

[LeeLenaleee]

Test is failing since the legendItem should not be allowed to be created without a datasetIndex.

I think that the best and cleanest approach is to add a baseLegendItem interface and a labelLegendItem interface, then let the current legendItem and doughnutLegendItem interfaces extend the base both with their index/datasetIndex mandatory. So it does not become a breaking change.

Or do we want to keep the typings more simple and remove the test that datasetIndex needs to be mandatory?

[etimberg]

hmmm, I think if we removed the mandatory datasetIndex everyone will have to check it, but it's more correct so I think removing the test is the best option here