fetch data from api app

node_modules/csv-writer/src/test/lang/promise.test.ts

@@ -0,0 +1,21 @@
+import {promisify} from '../../lib/lang/promise';
+import {strictEqual} from 'assert';
+import {assertRejected} from '../helper';
+
+describe('Promise', () => {
+    const greetAsync = (name: string, callback: (err: Error | null, result?: string) => void) => {
+        setTimeout(() => {
+            if (name === 'foo') callback(null, `Hello, ${name}!`);
+            else callback(new Error(`We don't know ${name}`));
+        }, 0);
+    };
+    const promisifiedFn = promisify(greetAsync);
+
+    it('promisify node style callback', async () => {
+        strictEqual(await promisifiedFn('foo'), 'Hello, foo!');
+    });
+
+    it('raise an error for error', async () => {
+        await assertRejected(promisifiedFn('bar'), "We don't know bar");
+    });
+});