If plugin is disabled, we should not modify the html at all (#28)

* If plugin is disabled, we should not modify the html at all

* Updating readme to reflect new recommendation of not including a blank meta tag - it will be added for us

Author: AnujRNair

README.md

@@ -29,11 +29,6 @@ new HtmlWebpackPlugin()
 new CspHtmlWebpackPlugin()
 ```
 
-Finally, add the following tag to your HTML template where you would like to add the CSP policy:
-```
-<meta http-equiv="Content-Security-Policy" content="">
-```
-
 ## Configuration
 
 This `CspHtmlWebpackPlugin` accepts 2 params with the following structure:

plugin.jest.js

@@ -508,15 +508,15 @@ describe('CspHtmlWebpackPlugin', () => {
   });
 
   describe('Enabled check', () => {
-    it('removes the empty Content Security Policy meta tag if enabled is the bool false', done => {
+    it("doesn't modify the html if enabled is the bool false", done => {
       const config = createWebpackConfig([
         new HtmlWebpackPlugin({
           filename: path.join(WEBPACK_OUTPUT_DIR, 'index.html'),
           template: path.join(
             __dirname,
             'test-utils',
             'fixtures',
-            'with-nothing.html'
+            'with-no-meta-tag.html'
           )
         }),
         new CspHtmlWebpackPlugin(
@@ -534,15 +534,15 @@ describe('CspHtmlWebpackPlugin', () => {
       });
     });
 
-    it('removes the empty Content Security Policy meta tag if the `cspPlugin.disabled` option in HtmlWebpack Plugin is true', done => {
+    it("doesn't modify the html if the `cspPlugin.enabled` option in HtmlWebpack Plugin is false", done => {
       const config = createWebpackConfig([
         new HtmlWebpackPlugin({
           filename: path.join(WEBPACK_OUTPUT_DIR, 'index.html'),
           template: path.join(
             __dirname,
             'test-utils',
             'fixtures',
-            'with-nothing.html'
+            'with-no-meta-tag.html'
           ),
           cspPlugin: {
             enabled: false
@@ -558,15 +558,15 @@ describe('CspHtmlWebpackPlugin', () => {
       });
     });
 
-    it('removes the empty Content Security Policy meta tag if enabled is a function which return false', done => {
+    it("doesn't modify the html if enabled is a function which return false", done => {
       const config = createWebpackConfig([
         new HtmlWebpackPlugin({
           filename: path.join(WEBPACK_OUTPUT_DIR, 'index.html'),
           template: path.join(
             __dirname,
             'test-utils',
             'fixtures',
-            'with-nothing.html'
+            'with-no-meta-tag.html'
           )
         }),
         new CspHtmlWebpackPlugin(
@@ -584,15 +584,15 @@ describe('CspHtmlWebpackPlugin', () => {
       });
     });
 
-    it('only removes the Content Security Policy meta tag from the HtmlWebpackPlugin instance which has been disabled', done => {
+    it("doesn't modify html from the HtmlWebpackPlugin instance which has been disabled", done => {
       const config = createWebpackConfig([
         new HtmlWebpackPlugin({
           filename: path.join(WEBPACK_OUTPUT_DIR, 'index-enabled.html'),
           template: path.join(
             __dirname,
             'test-utils',
             'fixtures',
-            'with-nothing.html'
+            'with-no-meta-tag.html'
           )
         }),
         new HtmlWebpackPlugin({
@@ -601,7 +601,7 @@ describe('CspHtmlWebpackPlugin', () => {
             __dirname,
             'test-utils',
             'fixtures',
-            'with-nothing.html'
+            'with-no-meta-tag.html'
           ),
           cspPlugin: {
             enabled: false

plugin.js

@@ -282,18 +282,13 @@ class CspHtmlWebpackPlugin {
       decodeEntities: false
     });
 
-    let metaTag = $('meta[http-equiv="Content-Security-Policy"]');
-
     // if not enabled, remove the empty tag
     if (!this.isEnabled(htmlPluginData)) {
-      metaTag.remove();
-
-      // eslint-disable-next-line no-param-reassign
-      htmlPluginData.html = $.html();
-
       return compileCb(null, htmlPluginData);
     }
 
+    let metaTag = $('meta[http-equiv="Content-Security-Policy"]');
+
     // Add element if it doesn't exist.
     if (!metaTag.length) {
       metaTag = cheerio.load('<meta http-equiv="Content-Security-Policy">')(