docs(ngAnimate): Change event to ng-enter

[stovenator]

The event needs to map to the css class, or else the css class won't fire

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[stovenator]

I signed it!

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[petebacondarwin]

@matsko - can you check this is correct and merge?

[gkalpak]

This doesn't seem correct (unless the documentation is wrong).
But there is definitely something that needs fixing.

[petebacondarwin]

It seem to me that the original wording is correct. See https://github.com/angular/angular.js/blob/master/src/ngAnimate/animateCss.js#L185
In other words, the event is mapped to the "DOM event", and that the class is then generated from this.

[gkalpak]

The problem is that in practice, it doesn't work as described in the docs (but I think there is another issue about this).

[petebacondarwin]

Can you provide a demo of this not working?
This line of code here seems to follow what the docs say:
https://github.com/angular/angular.js/blob/master/src/ngAnimate/animateCss.js#L528

[gkalpak]

I am pretty sure there was another issue (where I had commented) that showed the issue with enter and enter-active being added (without the ng- prefix). But I can't find it.

@matsko has pushed some fixes that may have taken care of the issue. I'll check and create a demo if it hasn't been fixed on master.

[gkalpak]

I found it: the issue is #12202 (which is not directily related, but lead me to noticing the unexpected(?) behaviour).

Here is the demo, I created for that issue.
(I would expect ng-enter/ng-enter-active to be added, but enter/enter-active are added instead. The same happens with the current snapshot.)