FASTTreeItem in Angular 15

This project was generated with Angular CLI version 15.

About

This is a reproduction of an issue involving use of the ChildrenDirective in FASTTreeItem and FASTTreeView leading to failure to render nested tree items in Angular. #6740

Console errors:

Uncaught TypeError: Cannot read properties of undefined (reading 'fast-fmoaic-304-c')
    at ChildrenDirective.getSource (node-observation.js:[60:22](https://github.com/microsoft/fast/blob/master/packages/web-components/fast-element/src/templating/node-observation.ts#L81))
    at ChildrenDirective.handleEvent (children.js:[18:36](https://github.com/microsoft/fast/blob/master/packages/web-components/fast-element/src/templating/children.ts#L100))
    at _ZoneDelegate.invoke (zone.js:372:26)
    at Zone.runGuarded (zone.js:144:47)
    at MutationObserver.<anonymous> (zone.js:128:29)

This reproduction uses Angular 15 and the following FAST packages:

"@microsoft/fast-element": "2.0.0-beta.23",
"@microsoft/fast-foundation": "3.0.0-alpha.27",
"@microsoft/fast-web-utilities": "6.0.0",

Development server

Run ng serve for a dev server. Navigate to http://localhost:4200/. The application will automatically reload if you change any of the source files.

Code scaffolding

Run ng generate component component-name to generate a new component. You can also use ng generate directive|pipe|service|class|guard|interface|enum|module.

Build

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Running unit tests

Run ng test to execute the unit tests via Karma.

Running end-to-end tests

Run ng e2e to execute the end-to-end tests via a platform of your choice. To use this command, you need to first add a package that implements end-to-end testing capabilities.

Further help

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