Add docker.df

src/test/docker-test.js

@@ -0,0 +1,24 @@
+/* jslint node:true */
+/* global it:false */
+/* global before:false */
+/* global after:false */
+/* global describe:false */
+
+'use strict';
+
+const common = require('./common.js'),
+    docker = require('../docker.js'),
+    expect = require('expect.js');
+
+describe('docker', function () {
+    const { setup, cleanup } = common;
+
+    before(setup);
+    after(cleanup);
+
+    it('can df', async function () {
+        const output = await docker.df();
+        expect(output).to.be.ok();
+        console.log(output);
+    });
+});