moment.local() fails to clear the timezone

[jorroll]

Similar to issue #86, a call to momentDate.local() fails to clear the timezone associated with momentDate.tz().

At the, ahem, moment, the only (supported) way I've found to clear the timezone is to use both momentdate.utc() and momentDate.local(). The first call clears the timezone and the second sets the moment to local time. I.e. momentDate.utc().local()

[mattjohnsonpint]

Agreed that _z should be cleared when .local() is called, but it shouldn't have any effect if it doesn't since local mode functions don't use _z. Can you give an example where it matters?

[jorroll]

I'm working from memory at the moment (😄), but I believe that currently, moment-timezone exhibits the following, undesired behavior:

const date = moment.tz('America/Los_Angeles');
date.tz() // => 'America/Los_Angeles'
date.local()
date.tz() // => 'America/Los_Angeles'

The following is what I expected to happen:

const date = moment.tz('America/Los_Angeles');
date.tz() // => 'America/Los_Angeles'
date.local()
date.tz() // => undefined

Specifically, once set, there is no straightforward way of clearing a moment's timezone info and resetting it to the local timezone.

I also tried date.tz(undefined) and date.tz(null). I found that date.tz('local') did work to clear the timezone, but it is most definitely a hack. It appears that, whenever you pass an invalid timezone to moment#tz(), the timezone info is cleared and an warning is logged to the console. Since "local" is an invalid timezone, it clears the timezone but also logs an error. momentDate.utc().local() is a better solution at the moment.

[mattjohnsonpint]

Agreed. Also, the same is true when setting the offset explicitly with .utcOffset(offset).

Will fix shortly.

[jorroll]

Thanks!!!