More utest attempts

src/__test__/App.test.js

@@ -2,13 +2,29 @@ import React from "react";
 import renderer from "react-test-renderer";
 
 import App from "../App";
-//FIXME:currently, I can't run the example that is in the expo documentation
-// -> https://docs.expo.io/guides/testing-with-jest/#unit-test
+
+jest.useFakeTimers();
 
 // NOTE: Just an toy example for verifying if Jest is running
-describe("<App />", () => {
-  it("has 1 child", () => {
-    // const tree = renderer.create(<App />).toJSON();
+describe("Jest initialization test", () => {
+  it("Knows how to sum", () => {
     expect(1 + 1).toBe(2);
   });
 });
+
+
+// NOTE: Testing a snapshot
+it('Renders correctly', () => {
+  const tree = renderer.create(<App />).toJSON();
+  expect(tree).toMatchSnapshot();
+});
+
+
+//FIXME:currently, I can't run the example that is in the expo documentation
+// -> https://docs.expo.io/guides/testing-with-jest/#unit-test
+// describe("<App />", () => {
+//   it("has 1 child", () => {
+//     const tree = renderer.create(<App />).toJSON();
+//     expect(tree.children.length).toBe(1);
+//   });
+// });