[pickers] Pass the date object to dayOfWeekFormatter and deprecate the string parameter

[michelengelen]

Description

The dayOfWeekFormatter received only a string as parameter and to handle this the user had to manually detect which day of the week he received before handling its formatting (if he intended to change something on that).
Now the formatting function receives the date object (according to the used adapter), so the flexibility is increased by a fair margin here.

As a way of fixing this the getWeekdays method will be deprecated and replaced by the new getWeek method in the adapters. This now returns an array of date objects for the week of the given date. The signature looks like this:

getWeek(value: TDate): TDate[];

The new signature for the dayOfWeekFormatter is now:

dayOfWeekFormatter?: (weekday: TDate) => string;

the default behaviour is kept the same (returning the initial of the weekday):

(weekday: TDate) => utils.format(weekday, 'weekdayShort').charAt(0).toUpperCase()

This introduces a minor breaking change.

Fixes #9984

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[mui-bot]

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Updated pages

• docs/data/date-pickers/adapters-locale/adapters-locale.md

These are the results for the performance tests:

Test case	Unit	Min	Max	Median	Mean	σ
Filter 100k rows	ms	-114.5	368.3	104	99.74	166.327
Sort 100k rows	ms	1,111.5	1,984.8	1,771.8	1,631.1	351.883
Select 100k rows	ms	872.8	1,213.1	872.8	993.48	119.076
Deselect 100k rows	ms	203.1	496	257.3	316.1	109.718

Generated by 🚫 dangerJS against 3f0eccf

[michelengelen]

@flaviendelangle could re-review? I have added the requested changes

[michelengelen]

@alexfauquette could you also take a look here, since @flaviendelangle is on PTO? Thanks! 🙇🏼‍♂️

[flaviendelangle]

Looks great 👌

[flaviendelangle]

Just living a small suggestion for the doc

[flaviendelangle]

The build error is weird, I'll have a look if you do not find its root cause

[flaviendelangle]

Great work!

[michelengelen]

@flaviendelangle argos seems flaky on this test :/

[flaviendelangle]

I approved the Argos changes