imp(tests): add sample test

Author: omarabid

package.json

@@ -4,6 +4,7 @@
     "description": "Simplify Front-End development",
     "main": "gulpfile.js",
     "dependencies": {
+        "@types/jest": "^26.0.14",
         "@types/react": "^16.9.23",
         "@types/react-dom": "^16.9.5",
         "lodash": "^4.17.15",
@@ -31,6 +32,7 @@
         "webpack-stream": "^5.2.1",
         "ts-loader": "^6.2.1",
         "typescript": "^3.8.2",
+        "jest": "^26.4.2",
         "node-sass": "^4.13.0"
     },
     "scripts": {

src/javascript/sum.test.tsx

@@ -0,0 +1,5 @@
+const sum = require('./sum');
+
+test('adds 1 + 2 to equal 3', () => {
+    expect(sum(1, 2)).toBe(3);
+});

src/javascript/sum.tsx

@@ -0,0 +1,5 @@
+function sum(a, b) {
+    return a + b;
+}
+
+module.exports = sum;