Added sleep function

Author: s1hofmann

lib/sleep.function.spec.ts

@@ -0,0 +1,16 @@
+import { sleep } from "./sleep.function";
+
+describe("sleep", () => {
+  it("should resolve after x ms", async () => {
+    // GIVEN
+    const timeout = 500;
+
+    // WHEN
+    const before = Date.now();
+    await sleep(timeout);
+    const after = Date.now();
+
+    // THEN
+    expect(after - before).toBeGreaterThanOrEqual(timeout);
+  });
+});

lib/sleep.function.ts

@@ -0,0 +1,3 @@
+export const sleep = async (ms: number) => {
+  return new Promise(resolve => setTimeout(resolve, ms));
+};