From 14b1a38dfa9ee6ca4132aa0754de05327b472aa5 Mon Sep 17 00:00:00 2001
From: Charles Blaxland <charles.blaxland@gmail.com>
Date: Thu, 14 Aug 2014 20:36:15 +1000
Subject: [PATCH] Read template file asynchronously

---
 index.js                      | 27 +++++++++++++----------
 spec/HtmlWebpackPluginSpec.js | 41 ++++++++++++++++++++++++-----------
 2 files changed, 44 insertions(+), 24 deletions(-)

diff --git a/index.js b/index.js
index 0e192bc..b48abd4 100644
--- a/index.js
+++ b/index.js
@@ -21,18 +21,23 @@ HtmlWebpackPlugin.prototype.apply = function(compiler) {
       templateFile = path.join(__dirname, 'default_index.html');
     }
 
-    var htmlTemplateContent = fs.readFileSync(templateFile, 'utf8');
-    var html = tmpl(htmlTemplateContent, templateParams);
-    var outputFilename = self.options.filename || 'index.html';
-    compiler.assets[outputFilename] = {
-      source: function() {
-        return html;
-      },
-      size: function() {
-        return html.length;
+    fs.readFile(templateFile, 'utf8', function(err, htmlTemplateContent) {
+      if (err) {
+        compiler.errors.push(new Error('HtmlWebpackPlugin: Unable to read HTML template "' + templateFile + '"'));
+      } else {
+        var html = tmpl(htmlTemplateContent, templateParams);
+        var outputFilename = self.options.filename || 'index.html';
+        compiler.assets[outputFilename] = {
+          source: function() {
+            return html;
+          },
+          size: function() {
+            return html.length;
+          }
+        };
       }
-    };
-    callback();
+      callback();
+    });
   });
 };
 
diff --git a/spec/HtmlWebpackPluginSpec.js b/spec/HtmlWebpackPluginSpec.js
index 766d87b..b1f15f1 100644
--- a/spec/HtmlWebpackPluginSpec.js
+++ b/spec/HtmlWebpackPluginSpec.js
@@ -6,7 +6,7 @@ var HtmlWebpackPlugin = require('../index.js');
 
 var OUTPUT_DIR = path.join(__dirname, '../dist');
 
-function testHtmlPlugin(webpackConfig, expectedResults, done, outputFile) {
+function testHtmlPlugin(webpackConfig, expectedResults, outputFile, done) {
   outputFile = outputFile || 'index.html';
   webpack(webpackConfig, function(err, stats) {
     expect(err).toBeFalsy();
@@ -37,7 +37,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'index_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, ['<script src="index_bundle.js"'], done);
+    }, ['<script src="index_bundle.js"'], null, done);
 
   });
 
@@ -52,7 +52,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: '[name]_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, ['<script src="util_bundle.js"', '<script src="app_bundle.js"'], done);
+    }, ['<script src="util_bundle.js"', '<script src="app_bundle.js"'], null, done);
   });
 
   it('allows you to specify your own HTML template', function(done) {
@@ -66,7 +66,7 @@ describe('HtmlWebpackPlugin', function() {
       },
       plugins: [new HtmlWebpackPlugin({template: path.join(__dirname, 'fixtures/test.html')})]
     },
-    ['<script src="app_bundle.js"', 'Some unique text'], done);
+    ['<script src="app_bundle.js"', 'Some unique text'], null, done);
   });
 
   it('works with source maps', function(done) {
@@ -78,7 +78,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'index_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, ['<script src="index_bundle.js"'], done);
+    }, ['<script src="index_bundle.js"'], null, done);
   });
 
   it('handles hashes in bundle filenames', function(done) {
@@ -89,7 +89,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'index_bundle_[hash].js'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, [/<script src="index_bundle_[0-9a-f]+\.js"/], done);
+    }, [/<script src="index_bundle_[0-9a-f]+\.js"/], null, done);
   });
 
   it('prepends the webpack public path to script src', function(done) {
@@ -101,7 +101,7 @@ describe('HtmlWebpackPlugin', function() {
         publicPath: 'http://cdn.example.com/assets/'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, ['<script src="http://cdn.example.com/assets/index_bundle.js"'], done);
+    }, ['<script src="http://cdn.example.com/assets/index_bundle.js"'], null, done);
   });
 
   it('handles subdirectories in the webpack output bundles', function(done) {
@@ -112,7 +112,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'assets/index_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, ['<script src="assets/index_bundle.js"'], done);
+    }, ['<script src="assets/index_bundle.js"'], null, done);
   });
 
   it('handles subdirectories in the webpack output bundles along with a public path', function(done) {
@@ -124,7 +124,7 @@ describe('HtmlWebpackPlugin', function() {
         publicPath: 'http://cdn.example.com/'
       },
       plugins: [new HtmlWebpackPlugin()]
-    }, ['<script src="http://cdn.example.com/assets/index_bundle.js"'], done);
+    }, ['<script src="http://cdn.example.com/assets/index_bundle.js"'], null, done);
   });
 
   it('allows you to configure the title of the generated HTML page', function(done) {
@@ -135,7 +135,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'index_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin({title: 'My Cool App'})]
-    }, ['<title>My Cool App</title>'], done);
+    }, ['<title>My Cool App</title>'], null, done);
   });
 
   it('allows you to configure the output filename', function(done) {
@@ -146,7 +146,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'index_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin({filename: 'test.html'})]
-    }, ['<script src="index_bundle.js"'], done, 'test.html');
+    }, ['<script src="index_bundle.js"'], 'test.html', done);
   });
 
   it('allows you to configure the output filename with a path', function(done) {
@@ -157,7 +157,7 @@ describe('HtmlWebpackPlugin', function() {
         filename: 'index_bundle.js'
       },
       plugins: [new HtmlWebpackPlugin({filename: 'assets/test.html'})]
-    }, ['<script src="index_bundle.js"'], done, 'assets/test.html');
+    }, ['<script src="index_bundle.js"'], 'assets/test.html', done);
   });
 
   it('allows you write multiple HTML files', function(done) {
@@ -174,9 +174,24 @@ describe('HtmlWebpackPlugin', function() {
           template: path.join(__dirname, 'fixtures/test.html')
         })
       ]
-    }, ['<script src="index_bundle.js"'], done);
+    }, ['<script src="index_bundle.js"'], null, done);
 
     expect(fs.existsSync(path.join(__dirname, 'fixtures/test.html'))).toBe(true);
   });
 
+  it('registers a webpack error if the template cannot be opened', function(done) {
+    webpack({
+      entry: path.join(__dirname, 'fixtures/index.js'),
+      output: {
+        path: OUTPUT_DIR,
+        filename: 'index_bundle.js'
+      },
+      plugins: [new HtmlWebpackPlugin({template: 'fixtures/does_not_exist.html'})]
+    }, function(err, stats) {
+      expect(stats.hasErrors()).toBe(true);
+      expect(stats.toJson().errors[0]).toContain('HtmlWebpackPlugin');
+      done();
+    });
+  });
+
 });