Add isStream

test/isStream/isStream.js

@@ -0,0 +1,2 @@
+const isStream = val => val !== null && typeof val === 'object' && typeof val.pipe === 'function';
+module.exports = isStream;

test/isStream/isStream.test.js

@@ -0,0 +1,13 @@
+const expect = require('expect');
+const isStream = require('./isStream.js');
+const fs = require('fs');
+
+test('isStream is a Function', () => {
+  expect(isStream).toBeInstanceOf(Function);
+});
+test('isStream returns true for streams', () => {
+  expect(isStream(fs.createReadStream('isStream.js'))).toBeTruthy();
+});
+test('isStream returns false for non-streams', () => {
+  expect(isStream({})).toBeFalsy();
+});