Add tests

Author: niminjie

Diff for: .gitignore

@@ -0,0 +1 @@
+node_modules

Diff for: README.md

@@ -1,5 +1,7 @@
 # HTML STRING REPLACE WEBPACK PLUGIN
 
+[![npm version](https://badge.fury.io/js/html-string-replace-webpack-plugin.svg)](https://badge.fury.io/js/html-string-replace-webpack-plugin)
+
 This is a webpack plugin that replace string in html files that created by `html-webpack-plugin`.   
 This is especially useful for adding some cdn prefix.
 
@@ -69,6 +71,7 @@ new HtmlStringReplace({
             // <script src="//cdn.baidu.com/static/build.js"> 
             match: /src=\"([^\"]*)\"/g,
             replacement: 'href="' + CDN_PREFIX + '$1"'
+       }
     ]
 })
 ```

Diff for: package.json

@@ -4,7 +4,7 @@
   "description": "webpack html string replacement plugin",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "jest"
   },
   "repository": {
     "type": "git",
@@ -21,5 +21,11 @@
   "bugs": {
     "url": "https://github.com/erraX/html-string-replace-webpack-plugin/issues"
   },
-  "homepage": "https://github.com/erraX/html-string-replace-webpack-plugin#readme"
+  "homepage": "https://github.com/erraX/html-string-replace-webpack-plugin#readme",
+  "dependencies": {
+    "jest": "^20.0.4"
+  },
+  "jest": {
+    "testRegex": "(/test/.*\\.spec.js)$"
+  }
 }

Diff for: test/replacestring.spec.js

@@ -0,0 +1,30 @@
+var HtmlStringReplace = require('../lib/HtmlStringReplace');
+
+describe('test string replacement', function () {
+    it('should replace string', function () {
+        var plugin = new HtmlStringReplace({
+            enable: true,
+            patterns: [
+                {
+                    // eg.
+                    // <link href="build.css">  =>
+                    // <link href="//cdn.baidu.com/static/build.css"> 
+                    match: /href=\"([^\"]*)\"/g,
+                    replacement: function (match, $1) {
+                        return 'href="//cdn.baidu.com/static/' + $1 + '"';
+                    }
+                },
+                {
+                    // eg.
+                    // <script src="build.js">  =>
+                    // <script src="//cdn.baidu.com/static/build.js"> 
+                    match: /src=\"([^\"]*)\"/g,
+                    replacement: 'src="//cdn.baidu.com/static/$1"'
+                }
+            ]
+        });
+
+        expect(plugin.replaceString('<link href="build.css">')).toBe('<link href="//cdn.baidu.com/static/build.css">');
+        expect(plugin.replaceString('<script src="build.js">')).toBe('<script src="//cdn.baidu.com/static/build.js">');
+    });
+});