feat(VDatePicker): restore weekday-format

[J-Sek]

Description

weekdayFormat existed in v2, but was not yet re-implemented.

Note: It is going to be ignored by custom date adapters until those packages get updated by community.

• date-fns is already printing with EEEEEE which equals to Intl's short
• day.js has dd hardcoded - i.e. narrow
• luxon uses Intl with short hardcoded

Markup:

<template>
  <v-container>
    <v-select
      label="Locale"
      variant="outlined"
      v-model="locale.current.value"
      :items="['en', 'de', 'pl', 'fr', 'ar']"
    />
    <v-date-picker
      :key="locale.current.value"
      class="mt-3"
      weekday-format="short"
    />
  </v-container>
</template>

<script setup>
  import { useLocale } from 'vuetify'
  const locale = useLocale()
</script>

[johnleider]

We might need to operate under the idea that other libraries aren't going to update and support this in the future.

[J-Sek]

We might need to operate under the idea that other libraries aren't going to update and support this in the future.

Devs can extend adapters to force particular weekday format or make it support new arguments by copy/pasting from the date-io PR linked above.

[johnleider]

Devs can extend adapters to force particular weekday format or make it support new arguments by copy/pasting from the date-io PR linked above.

Is this something worth putting into an alert in the docs?

[J-Sek]

Is this something worth putting into an alert in the docs?

Alert.. not really. More like a full blog post to cover differences & limitations. For now we have the disclaimer at the end of the prop description in API docs and I feel it is fine. People are asking for help with their specific adapters from time to time, so I guess we'll see their voices on Discord. You could touch on it in v3.8.6 announcement with something like "week format supported by default date adapter, see [issueID] for more details"

IMO, getting built-in adapter better (and extendable: #21252) makes it easier for devs to achieve expected i18n goals without having to use 3rd party libraries.

[KaelWD]

Moved to dev