Suitescript adds .0 to numbers in array

In Suitescript 2.0 I want to check if an ID does not match with one of the IDs in the array below:

var interfaceStatusArray1 = [14, 15, 17, 20, 25, 26];

In the debugger I see that .0 is added to every value in the array :

Now if my ID is 1 and I do the following check:

 interfaceStatusArray1.indexOf(lineItemFieldValues.interfaceStatusID) == -1

then this will always be true, because the numbers have .0 added.

Is there a way to remove the .0? I already tried Math.trunc, but Netsuite gives me this error:

TypeError: Cannot find function trunc in object [object Math].

I also reproduced the code in jsfiddle however in jsfiddle it works, because it gets into false: https://jsfiddle.net/7fnxoz1r/1/

I am quite new to Suitescript 2.0 but it also seems that suitescript 2.0 does not allow array.includes.

Answer

Why not set interfaceStatusArray1 as a string array? If needed you can turn them to number back/forward using the primitive classes String(val)/Number(val)