6.2.0-alpha.14 Angular props are reinitialized by StorybookWrapperComponent

[vprothais]

Describe the bug
When we have a component with a prop, not declared as an input, it is reinitialized to its default value even if the ngOnInit set a value.
In the example below I assign an array to the prop. I should have the "Hello" text displayed, but I have an empty view for the component.

To Reproduce
Create a simple component with a prop assigned in the ngOnInit :

import {Component, OnInit} from "@angular/core";

@Component({
    selector: "test",
    template:  `<p *ngFor="let entry of prop">{{entry.value}}</p>`
})
export class TestComponent implements OnInit {
    private prop = [];

    public ngOnInit() {
        this.prop = [{value: "Hello"}];
    }
}

Expected behavior
I should have in my canvas a p tag with "Hello" as innerText.

System
System:
OS: Linux 5.3 Ubuntu 19.10 (Eoan Ermine)
CPU: (2) x64 Intel(R) Core(TM) i7-6600U CPU @ 2.60GHz
Binaries:
Node: 12.18.4 - /usr/local/bin/node
Yarn: 1.21.1 - /usr/bin/yarn
npm: 6.14.6 - /usr/local/bin/npm
Browsers:
Chrome: 84.0.4147.125
Firefox: 78.0.2
npmPackages:
@storybook/addon-actions: ^6.2.0-alpha.14 => 6.2.0-alpha.14
@storybook/addon-essentials: ^6.2.0-alpha.14 => 6.2.0-alpha.14
@storybook/addon-links: ^6.2.0-alpha.14 => 6.2.0-alpha.14
@storybook/addons: ^6.2.0-alpha.14 => 6.2.0-alpha.14
@storybook/angular: ^6.2.0-alpha.14 => 6.2.0-alpha.14
@storybook/theming: ^6.2.0-alpha.14 => 6.2.0-alpha.14

Can also be reproduced in alpha.15.

Additional context
This issue is probably linked to this PR : #13507

The prop is reset by the ngAfterViewInit call of StorybookWrapperComponent.
On the following lines :

initialOtherProps.forEach(function (p) {
  _this.storyComponentElementRef[p] = initialProps[p];
});

initialProps contains an empty array for prop in my example.

ping @ThibaudAV

[ThibaudAV]

There are several issues more or less related to the same problem (ex: #11613, #12946)

If we change this it causes braking changes.
Which IMHO would be good things. And would "force" users to interact only with Angular Input/Output.
And we could add something like this overrideComponentProps which would overload component props as before (even if it's bad to do it)

[valentinpalkovic]

Not reproducible in Storybook 7 / Angular 15 anymore. Therefore, I am closing this. Please reopen the issue if you still encounter it. Please provide a Stackblitz reproduction in this case (https://storybook.new)