How to write test case for @viewchild element referenced for input checkbox?

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I am new to test case in angular. I have a input type checkbox which has element ref id of #checkbox.
Below is code snippet. How to write test case for masterToggle function in below code?

What I have tried:

HTML code:
input type="checkbox" class="nodecheckbox" #checkbox [disabled]="isCheckboxDisabledForSelectAll()" (change)="masterToggle(data)" > 

Ts code:
@ViewChild('checkbox') checkbox;

function masterToggle(){
this.checkbox.nativeElement.checked = false;
this.checkbox.nativeElement.indeterminate = false;
}