perf(uniq): Improve performance of uniq function (#40)

* fix<uniq>: make uniq function to use Set

* test(uniq): write additional test codes for uniq function

* Update src/array/uniq.ts

---------

Co-authored-by: Sojin Park <raon0211@gmail.com>

src/array/uniq.spec.ts

@@ -5,4 +5,35 @@ describe('uniq', () => {
   it('uniq function creates unique elements from the array passed as an argument.', () => {
     expect(uniq([11, 2, 3, 44, 11, 2, 3])).toEqual([11, 2, 3, 44]);
   });
+  it('uniq function works with strings.', () => {
+    expect(uniq(['a', 'b', 'b', 'c', 'a'])).toEqual(['a', 'b', 'c']);
+  });
+  it('uniq function works with boolean values.', () => {
+    expect(uniq([true, false, true, false, false])).toEqual([true, false]);
+  });
+  it('uniq function works with nullish values.', () => {
+    expect(uniq([null, undefined, null, undefined])).toEqual([null, undefined]);
+  });
+  it('uniq function works with empty arrays.', () => {
+    expect(uniq([])).toEqual([]);
+  });
+  it('uniq function works with multiple types.', () => {
+    expect(uniq([1, 'a', 2, 'b', 1, 'a'])).toEqual([1, 'a', 2, 'b']);
+  });
+  it('uniq function keeps its original order.', () => {
+    expect(uniq([1, 2, 2, 3, 4, 4, 5])).toEqual([1, 2, 3, 4, 5]);
+  });
+  it('uniq function should create a new array.', () => {
+    const array = [1, 2, 3];
+    const result = uniq(array);
+
+    expect(result).toEqual([1, 2, 3]);
+    expect(result).not.toBe(array);
+  });
+  it('uniq function should not mutate the original array.', () => {
+    const array = [1, 2, 3, 2, 1, 3];
+    uniq(array);
+
+    expect(array).toEqual([1, 2, 3, 2, 1, 3]);
+  });
 });

src/array/uniq.ts

@@ -13,15 +13,5 @@
  * // result will be [1, 2, 3, 4, 5]
  */
 export function uniq<T>(arr: T[]): T[] {
-  const result: T[] = [];
-
-  for (const item of arr) {
-    if (result.includes(item)) {
-      continue;
-    }
-
-    result.push(item);
-  }
-
-  return result;
+  return Array.from(new Set(arr));
 }