Option for determining if tick is major

[benmccann]

The current code has hardcoded that a major tick is one that aligns with startOf(value, majorUnit). However, I've found many cases where I want a different behavior. E.g. in the financial charts we don't have weekends, so we might want to say the major tick is the first weekday of the month so that we have a majorTick begin each month. This adds an option called isMajor which takes a function to make the logic configurable.

[kurkle]

I think you should be able to change major in afterBuildTicks?

[benmccann]

I think you should be able to change major in afterBuildTicks?

As a user, it's much harder to create an entirely new scale type overriding afterBuildTicks than it is to specify an option on an existing scale type. I'd also have to access numerous private variables in order to accomplish that in afterBuildTicks

[kurkle]

I think you should be able to change major in afterBuildTicks?

As a user, it's much harder to create an entirely new scale type overriding afterBuildTicks than it is to specify an option on an existing scale type. I'd also have to access numerous private variables in order to accomplish that in afterBuildTicks

I was referring to the callback: https://www.chartjs.org/docs/latest/axes/#callbacks

[benmccann]

Ah, yeah, that would probably work if we made _adapter and _unit / _majorUnit public or added them as callback arguments. We'd also need the fix this is making in getLabelForIndex

[benmccann]

I think this is actually required after all to avoid major performance regression in #6274. I shared an explanation in Slack. Maybe easier to discuss there to cover the different cases