Finished

Test Name	Status
empty	Pass
no nesting	Pass
flattens a nested array	Pass
flattens array with just integers present	Pass
5 level nesting	Pass
6 level nesting	Pass
undefined values are omitted from the final result	Pass
null values are omitted from the final result	Pass
consecutive null values at the front of the array are omitted from the final result	Pass
consecutive null values in the middle of the array are omitted from the final result	Pass
6 level nested array with null values	Pass
all values in nested array are null	Pass

 //
 /**
+ * @param {any[]} arr
+ * @returns {any[]}
+ * Flattens a nested array of any depth, excluding null and undefined values.
+ *
+ * @param {any[]} arr - The nested array to flatten
+ * @returns {any[]} - A flattened array with all nested elements
+ *
+ * Edge Cases Handled:
+ * - Empty arrays
+ * - Arrays with null values
+ * - Arrays with undefined values
+ * - Arrays with mixed data types
+ * - Deeply nested arrays
+ * - Non-array inputs
  */
 export const flatten = (arr) => {
+  throw new Error('Remove this line and implement the function');
+  // Edge Case: Handle non-array inputs
+  if (!Array.isArray(arr)) {
+    return [];
+  }
+  const result = [];
+  for (let i = 0; i < arr.length; i++) {
+    const element = arr[i];
+    // Edge Case: Skip null and undefined values
+    if (element === null || element === undefined) {
+      continue;
+    }
+    // Edge Case: Handle nested arrays
+    if (Array.isArray(element)) {
+      const flattened = flatten(element);
+      result.push(...flattened);
+    } else {
+      result.push(element);
+    }
+  }
+  // Edge Case: Return empty array for empty inputs
+  return result;
 };

@ngel