mexican wave: done

Author: nerdrun

mexican_wave/main.js

@@ -1,9 +1,12 @@
 function wave(str){
+  return [...str].map((val, idx) => `${str.slice(0, idx)}${val.toUpperCase()}${str.slice(idx + 1)}`).filter(x => x !== str);
+  return [...str].reduce((acc, cur, idx) => (cur.trim() ? acc.push(`${str.slice(0, idx)}${cur.toUpperCase()}${str.slice(idx + 1)}`) : acc, acc), []);
+
   const result = [];
   for(let i = 0; i < str.length; i++) {
-    const split = str.split('');
-    split[i] = split[i].toUpperCase();
-    result.push(split.join(''));
+    if(str[i].trim()) { 
+      result.push(`${str.slice(0, i)}${str[i].toUpperCase()}${str.slice(i + 1, str.length)}`);
+    }
   }
   return result;
 }

mexican_wave/main.test.js

@@ -16,4 +16,13 @@ describe('Mexican wave test with full text', () => {
   test('wav returns ["Wav", "wAv", "waV"]', () => {
     expect(wave('wav')).toStrictEqual(['Wav','wAv','waV']);
   });
+  test("hello returns ['Hello', 'hEllo', 'heLlo', 'heLlo', 'hellO']", () => {
+    expect(wave('hello')).toStrictEqual(['Hello', 'hEllo', 'heLlo', 'helLo', 'hellO']);
+  });
+});
+
+describe('Mexican wave test with full text and blank', () => {
+  test('wa v returns ["Wa v", "wA v", "wa V"]', () => {
+    expect(wave('wa v')).toStrictEqual(['Wa v', 'wA v', 'wa V']);
+  });
 });