Child queries for @deferred components are not properly reset when component is removed

[leonsenft]

Consider the following example:

@Component(
  selector: 'example',
  template: '''
    <div *ngIf="show">
      <expensive @deferred></expensive>
    </div>
  ''',
  directives: [ExpensiveComponent, NgIf],
)
class ExampleComponent {
  @ViewChild(ExpensiveComponent)
  var deferredChild;

  bool get show => ...;
}

The deferredChild query is properly set with the deferred component when loaded; however, it's not reset to null when the enclosing structural directive removes the deferred component.

[matanlurey]

@leonsenft I am assuming this could be a known issue and fixed in 5.1/5.0.1, right?

[matanlurey]

@leonsenft My guess is this is the same issue as #1539?

[leonsenft]

Possibly, but IIRC I think we just don't generate the code to invalidate queries in this case.

[leonsenft]

Oh but this example uses the correct template, unlike the issue #1539.

[matanlurey]

Ah OK, good point. I'll take a look after #1539 in any case.

[matanlurey]

I'm hoping this is just #1539, but I'll validate after.

[matanlurey]

This does work after #1539, and I'm adding a test in matanlurey@b328544.