Added jest, jest-puppeteer and jest-image-snapshot for e2e tests

webpack.config.e2e.js

@@ -0,0 +1,58 @@
+const path = require('path')
+
+const jsRule = {
+  test: /\.js$/,
+  exclude: /node_modules/,
+  use: {
+    loader: 'babel-loader'
+  }
+}
+
+const amdRule = {
+  parser: {
+    amd: false // https://github.com/lodash/lodash/issues/3052
+  }
+}
+const scssRule = {
+  // load scss to string
+  test: /\.scss$/,
+  use: [
+    { loader: 'css-to-string-loader' },
+    { loader: 'css-loader' },
+    { loader: 'sass-loader' }
+  ]
+}
+
+module.exports = {
+  mode: 'development',
+  target: 'web',
+  entry: {
+    mermaid: './src/mermaid.js',
+    e2e: './e2e/platform/viewer.js'
+  },
+  node: {
+    fs: 'empty' // jison generated code requires 'fs'
+  },
+  output: {
+    path: path.join(__dirname, './dist/'),
+    filename: '[name].js',
+    library: 'mermaid',
+    libraryTarget: 'umd',
+    libraryExport: 'default'
+  },
+  devServer: {
+    contentBase: [
+      path.join(__dirname, 'e2e', 'platform'),
+      path.join(__dirname, 'dist')
+    ],
+    compress: true,
+    port: 9000
+  },
+  module: {
+    rules: [amdRule, jsRule, scssRule]
+  },
+  externals: {
+    mermaid: 'mermaid'
+  },
+  devtool: 'source-map'
+}