DateTimeRangeValidator not usable caused by DateFormat validation or incorrect translation format type

[andigehle]

When using the DateTimeRangeValidator and submitting a form with such an date which is invalid, the following error messages are used: (See the placeholder definition in lower case "datetime")

flow-development-collection/Neos.Flow/Resources/Private/Translations/en/ValidationErrors.xlf

Lines 33 to 39 in 8b2f13e

	<source>The given date must be between {0,datetime,datetime} and {1,datetime,datetime}</source>
	</trans-unit>
	<trans-unit id="1324315107" xml:space="preserve">
	<source>The given date must be after {0,datetime,datetime}</source>
	</trans-unit>
	<trans-unit id="1324315115" xml:space="preserve">
	<source>The given date must be before {0,datetime,datetime}</source>

The translation string like {1, datetime, datetime} goes through the DateTimeFormatter and validates by DateReader::validateFormatType

flow-development-collection/Neos.Flow/Classes/I18n/Cldr/Reader/DatesReader.php

Line 349 in 8b2f13e

public static function validateFormatType(string $formatType): void

The validation here checks hard on camelcase value "dateTime" and so the translation placeholder "datetime" throws an error to be not a valid format.

Exception: Provided formatType, "datetime", is not one of allowed values.
Trace:
Neos\Flow\I18n\Cldr\Reader\DatesReader_Original::validateFormatType("datetime")
Neos\Flow\I18n\Formatter\DatetimeFormatter_Original::format(DateTime, Neos\Flow\I18n\Locale, array|1|)
Neos\Flow\I18n\FormatResolver_Original::resolvePlaceholders("The given date must be after {0,datetime,datetime}", array|1|, Neos\Flow\I18n\Locale)

Possible solution:

• Change the placeholder string in all translation files for DateTimeRange from "datetime" to "dateTime"