4.0.0-1: context.cmdFormatter & start.format is not a function

[fullstackfool]

We've been using eventSources like:

{
          events({start, end, timeZone}, callback) {
            self.$http.get(`/holidays`, {
                timezone: timezone,
                start: start.format('YYYY/MM/DD')
            }).then(response => {
              callback(response.data.data)
            })
          },
          color: 'yellow',
          textColor: 'black',
},

Recently receiving errors of start.format is not a function.

Logging start shows it to be an object:

{
    end: Sun Nov 11 2018 00:00:00 GMT+0000 (Greenwich Mean Time) {}
    endStr: "2018-11-11T00:00:00Z"
    start: Sun Sep 30 2018 00:00:00 GMT+0100 (British Summer Time) {}
    startStr: "2018-09-30T00:00:00+01:00"
    timeZone: "local"
}

end:

f ( ) {
        if (!isResolved) {
            isResolved = true;
            success.apply(this, arguments);
        }
}

If i fix the format issue by updating to:

{
          events({start, end, timeZone}, callback) {
            self.$http.get(`/holidays`, {
                start: moment(start).format('YYYY/MM/DD'), 
                timezone: timezone
            }).then(response => {
              callback(response.data.data)
            })
          },
          color: 'yellow',
          textColor: 'black',
},

Then we get a new error: TypeError: context.cmdFormatter is not a function

Versions:
vue-full-calendar: 4.0.0-1
fullcalendar: 4.0.0-alpha.2
moment: 2.22.2
moment-timezone: 0.5.21

I suspect we've changed another dependacy, which in turn has effected fullcalendar, but i can't figure out what. Does this error look familiar to anyone?

[BrockReece]

What happens if you log out moment(start), are you getting a valid moment obj?

[fullstackfool]

Invalid object.

Tracked the issue to when vue-full-calendar is using fullcalendar: 4.0.0-alpha.2. Forcing it to use 4.0.0-alpha fixes the issue.

[ash-rain]

+1 Subscribing. Having the same issue with the new alpha.

[BrockReece]

I am guessing then this is probably an error with fullcalendar: 4.0.0-alpha.2 rather than this repo. Is it worth opening an issue on their repo?

I am happy to fix the version of fullcalendar though to the more stable version if this is a blocker?

[BrockReece]

I am reading their release notes for v4, it looks like there is a section outlining some changes in 'Event Source Function'

Have you read the docs?
Seems like the fetchInfo obj has some additional fields for startStr and endStr. Are they worth trying?

[JackPriceBurns]

It seems the first argument is this fetchInfo object that has both the start and the end date time stamps. The start and end are no longer passed separately? And the other arguments seem to return promises, not sure what they do.

[fullstackfool]

Quite possibly - looking into it now.

The fixed version would be a good temporary fix, thanks!

Edit: Also, if the package is going to use the alpha version of fullcalendar, shouldn't the local v4.0.0-1 release also be marked as Pre-release?

[fullstackfool]

Yeah, so the events have been combined, which you can then use to instantiate a moment object.

Then we get a new error: TypeError: context.cmdFormatter is not a function

Now going to try using an event url, instead of the function

[identy]

// titleFormat: 'MMMM'

error in title format

[Xalior]

This bug still exists in the final release of fullcal, and is in the base library itself outwith of the vue integrations it seems (I can reproduce it on the base library, exact same issues as @fullstackfool reports above)