throw helpful error to diagnose broken builds

README.md

@@ -5,6 +5,7 @@ Mock http requests made using fetch (or [isomorphic-fetch](https://www.npmjs.com
 - Browser tests: `require('fetch-mock)` 
 - Server side tests running in nodejs 4 or higher: `require('fetch-mock/server')`
 - Server side tests running in nodejs 0.12 or lower: `require('fetch-mock/es5/server)`
+
 You will need to ensure `fetch` and `Promise` are already available as globals in your environment
 
 

karma.conf.js

@@ -12,7 +12,7 @@ module.exports = function(karma) {
 			'test/client.js': ['browserify']
 		},
 		browserify: {
-				transform: ['babelify'],
+				transform: [['babelify', {	presets: ['es2015'] }]],
 				debug: true
 		},
 		browsers: ['Chrome'],

package.json

@@ -32,7 +32,7 @@
     "babel": "^6.0.15",
     "babel-cli": "^6.1.2",
     "babel-preset-es2015": "^6.1.2",
-    "babelify": "^7.0.0",
+    "babelify": "^7.2.0",
     "browserify": "^12.0.0",
     "chai": "^2.3.0",
     "karma": "^0.12.31",

src/client.js

@@ -1,5 +1,9 @@
 'use strict';
 
+if (!window) {
+	throw 'Incorrect fetch-mock: require(\'fetch-mock/server\') in nodejs >= 4, or require(\'fetch-mock/es5/server\' in nodejs 0.12.x';
+}
+
 const FetchMock = require('./fetch-mock');
 
 module.exports = new FetchMock({