ZonedDateTime::toDateTime and getDateTime conflict

[solodkiy]

In ZonedDateTime class we have two methods which looks almost the same, but different in return types:

• public function toDateTime() : \DateTime
• public function getDateTime() : LocalDateTime

To avoid misunderstanding and confuse I propose rename toDateTime to toNativeDateTime.
This approach could be used in other conversions in and from native types. For example:

• Period::fromDateInterval -> Period::fromNativeDateInterval
• Period::toDateInterval -> Period::toNativeDateInterval
• LocalDateRange::toDatePeriod -> LocalDateRange::toNativeDatePeriod
• TimeZone::fromDateTimeZone -> TimeZone::fromNativeDateTimeZone
  etc..

Another variant is use Php prefix (toDateTime -> toPhpDateTime).

[tigitz]

IMO, the Native prefix makes sense, I'm 👍 on this it helps readability and reduce ambiguity. I've wondered myself while trying to autocomplete method calls if the suggested DatePeriod for example was a library class or the native one.

However I would keep the getDateTime as it is since it means it is getting the DateTime part of the ZonedDateTime. Using the to prefix would suggest it's transforming the object into another one which is not the case here.

@BenMorel wdyt ?

[solodkiy]

Some of get*()/to*() discussion was there: #48

[BenMorel]

LGTM as well with the Native prefix. @solodkiy You're welcome to open a PR to create the new (to|from)Native*() methods, and deprecate existing ones. We'll remove them in 0.5.0.

The getDateTime() method is in line with the discussion we had in #48, so it looks good as it is!