handling of argument objects in javascript

attempting to create a function that will return an array with the first n elements of a given array. It must have the following handling:

• should return an array with the first n elements of the array
• should return an array with the first element if n is not a number, is zero, or negative
• should return the entire array if n is > length
• should work on an arguments object
• should return an empty array if array is not an array

I'm having trouble satisfying the "should work on an arguments object" while using the following code. When I add a line of code to convert the arguments object into an array then it raises an error with "should return an empty array if array is not an array" - because we're automatically converting the argument into an array. Thank you in advance for any help.

_.first = function (array, n) {
  
  array = Array.from(array);   
     
  if (!Array.isArray(array)) return [];
  
  if (isNaN(n) || n <= 0) return [array[0]];
  
  if (array.length - 1 < n) return array;
  
  return array.slice(0, n);
   
};

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