solution

src/arrayMethodSort.js

@@ -4,8 +4,39 @@
  * Implement method Sort
  */
 function applyCustomSort() {
-  [].__proto__.sort2 = function(compareFunction) {
-    // write code here
+  [].__proto__.sort2 = function (compareFunction) {
+    const array = this;
+    const length = array.length;
+
+    const compare =
+      compareFunction ||
+      function (a, b) {
+        const sA = String(a);
+        const sB = String(b);
+
+        if (sA > sB) {
+          return 1;
+        }
+
+        if (sA < sB) {
+          return -1;
+        }
+
+        return 0;
+      };
+
+    for (let i = 0; i < length; i++) {
+      for (let j = 0; j < length - 1 - i; j++) {
+        if (compare(array[j], array[j + 1]) > 0) {
+          const temp = array[j];
+
+          array[j] = array[j + 1];
+          array[j + 1] = temp;
+        }
+      }
+    }
+
+    return array;
   };
 }