Ember.js ArrayProxy insertAt() Method

import Route from '@ember/routing/route';

export default class ListRoute extends Route {
    list = [1, 2, 3, 5, 6, 7, 8, 9];
    item;
    idx;
    model() {
        return this.list;
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        controller.set('list', this.list);
        controller.set('item', this.item);
        controller.set('idx', this.idx);
    }
}

import Ember from 'ember';
import { clear, addObject, indexOf }
    from '@ember/array';

export default Ember.Controller.extend({
    actions: {
        insertItem(ind, item) {
            this.list.insertAt(ind, JSON.parse(item));
        },
        clearList() {
            this.list.clear();
        },
        getIndex(item) {
            let res = this.list.indexOf(JSON.parse(item));
            res != -1 ? alert(`Index of ${item} is ${res}`) 
            : alert(`list does not contains ${item}`);
        },
    },
});

{{page-title "insertAt"}}
<h3>Here is a list of Items: </h3>
<ul>
    {{#each @model as |i|}}
        <li>{{i}}</li>
    {{/each}}
</ul>
<br />
<div>
    <label>Enter Item: </label>
    {{input value=this.item2}}
</div>
<div>
    <input
        type="button"
        id="first-index-item"
        value="Get Index"
        {{action "getIndex" this.item2}}
    />
</div>
<br />
<div>
    <label>Enter Index: </label>
    {{input value=this.item}}
</div>
<br />
<div>
    <label>Enter Item: </label>
    {{input value=this.item3}}
</div>
<div>
    <input
        type="button"
        id="insert-item"
        value="Insert Item"
        {{action "insertItem" this.item this.item3}}
    />
</div>
<br />
<input type="button" id="clear-items"
  value="Clear" {{action "clearList"}} />
{{outlet}}

import Route from '@ember/routing/route';

export default class PartyRoute extends Route {
    partyItems = [
        'Oxygen',
        'Source Code',
        'Infine',
        'Tenet',
        'SpiderHead',
        'The Thing',
        'A Quiet Place',
        'The Invisible Man',
        'Looper',
        'Ad Astra'
    ];
    temp = [
        'Shutter Island',
        'Matrix',
        'Avatar',
        'Fantastic Beast',
        'Avengers',
        'Fantastic four',
        'Hult',
        'Superman',
        'Spiderman',
        'The Batman'
    ];
    item;
    idx;
    model() {
        return this.partyItems;
    }
    setupController(controller, model) {
        super.setupController(controller, model);
        controller.set('partyItems', this.partyItems);
        controller.set('item', this.item);
        controller.set('idx', this.idx);
        controller.set('temp', this.temp);
    }
}

import Ember from 'ember';
import { indexOf, pushObjects, insertAt } from '@ember/array';

export default Ember.Controller.extend({
    actions: {
        insertItem(ind, item) {
            this.partyItems.insertAt(ind, item);
        },
        push_item(data) {
            this.partyItems.pushObjects(data);
        },
        getItem(item) {
            let res = this.partyItems.indexOf(item);
            res != -1 ? alert(`Index of ${item} is ${res}`)
            : alert(`list does not contains ${item}`);
        },
    },
});

{{page-title "insertAt"}}
<h3>Here is a list of items: </h3>
<ul>
    {{#each @model as |party|}}
        <li>{{party}}</li>
    {{/each}}
</ul>
<br /><br />
<div>
    <label>Enter Index: </label>
    {{input value=this.item}}
</div>
<br />
<div>
    <label>Enter Item: </label>
    {{input value=this.item2}}
</div>
<div>
    <input
        type="button"
        id="insert-item"
        value="Insert Item"
        {{action "insertItem" this.item this.item2}}
    />
</div>
<br />
<div>
    <label>Enter Item: </label>
    {{input value=this.item3}}
</div>
<div>
    <input
        type="button"
        id="contains-item"
        value="Get Index"
        {{action "getItem" this.item3}}
    />
</div>
<br />
<input
    type="button"
    id="contains-item"
    value="Add Movies"
    {{action "push_item" this.temp}}
/>
{{outlet}}