ngAnimateSwap is not compatible with ngIf

[bersLucas]

I'm submitting a ...

• bug report
• feature request
• other

Current behavior:

ngAnimateSwap registers a comment of the element, not the element itself, so if an element contains the ng-if attribute, ng-animate-swap will not work.

Expected / new behavior:

Having a conditional element also be animated if it's visible.

Minimal reproduction of the problem with instructions:

1. Have an element with both ng-animate-swap and ng-if
2. The element will always be invisible, as it swaps the comments.

https://codepen.io/anon/pen/LrgBwY

AngularJS version: 1.7.2

Browser: [all]

(tested on FF 62, OSX High Seirra )

[gkalpak]

The problem is that both ngIf and ngAnimateSwap have a priority of 600, which means that (while both are terminal directives) they are executed on top of each other (essentially messing each other's comment node).

I can't be sure, but it seems like an oversight to me. ngAnimateSwap should have a lower priority.
As a workaround, you can overwrite ngAnimateSwap's default priority (demo):

angular.
  module('myApp', ['ngAnimate']).
  ...
  decorator('ngAnimateSwapDirective', $delegate => {
    // Give `ngAnimateSwap` a lower priority than `ngIf`'s 600.
    $delegate[0].priority = 599;
    return $delegate;
  });

Ideally, we should add this fix into ngAnimate, but I wonder if it might break some other usecase.

[codymikol]

Is there any reason the team has decided this will not get a fix? Would you accept a community PR?

[gkalpak]

We haven't made our final decision yet (we'll do this week). My main concern is the possibly breaking change (as mentioned in #16616 (comment)).

[petebacondarwin]

The reason that this has been moved to 1.7.x - won't fix is that we are now in LTS mode, which means that we are only fixing security and other significant bugs. But what @gkalpak is referring to, is that we are considering one more bug fix release, which may contain some issues from this milestone.