Issue 5535 - Replace our module system with webpack

webpack_runner.js

Index: webpack_runner.js
diff --git a/webpack.config.js b/webpack_runner.js
similarity index 58%
rename from webpack.config.js
rename to webpack_runner.js
index 3e061af1b2a4a25c60a261bd31ba91db127f05f5..87fe97b929554a1e52d1bc69e664a2f1d2e49ffc 100644
--- a/webpack.config.js
+++ b/webpack_runner.js
@@ -16,14 +16,60 @@
  */
 
 const path = require("path");
+const process = require("process");
+
+const MemoryFS = require("memory-fs");
+const webpack = require("webpack");
 
 let {EXTENSION_PATH, ENTRY_POINTS, OUTPUT_PATH, BUNDLE_NAME,
-     RESOLVE_PATHS, INFO_PATH} = require("process").env;
+     RESOLVE_PATHS} = require("process").env;
+
+// Copied from adblockpluscore/test_runner.js
+function webpackInMemory(bundleFilename, options)
+{
+  return new Promise((resolve, reject) =>
+  {
+    // Based on this example
+    // https://webpack.js.org/api/node/#custom-file-systems
+    let memoryFS = new MemoryFS();
+
+    options.output = {filename: bundleFilename, path: "/"};
+    let webpackCompiler = webpack(options);
+    webpackCompiler.outputFileSystem = memoryFS;
+
+    webpackCompiler.run((err, stats) =>
+    {
+      // Error handling is based on this example
+      // https://webpack.js.org/api/node/#error-handling
+      if (err)
+      {
+        let reason = err.stack || err;
+        if (err.details)
+          reason += "\n" + err.details;
+        reject(reason);
+      }
+      else if (stats.hasErrors())
+        reject(stats.toJson().errors);
+      else
+      {
+        let bundle = memoryFS.readFileSync("/" + bundleFilename, "utf-8");
+        memoryFS.unlinkSync("/" + bundleFilename);
+        resolve(bundle);
+      }
+    });
+  });
+}
 
-module.exports = {
+webpackInMemory(BUNDLE_NAME, {
   context: EXTENSION_PATH,
-  devtool: "source-map",
+  devtool: "inline-source-map",
   entry: ENTRY_POINTS.split(" "),
+  module: {
+    rules: [{
+      test: /info.js$/,
+      use: ["info-loader"]
+    }]
+  },
   output: {
     path: OUTPUT_PATH,
     filename: BUNDLE_NAME
@@ -31,7 +77,6 @@ module.exports = {
   resolve: {
     modules: RESOLVE_PATHS.split(" "),
     alias: {
-      info$: INFO_PATH,
       // Prevent builtin Node.js modules from being used instead of our own when
       // the names clash. Once relative paths are used this won't be necessary.
       url$: "url.js",
@@ -71,6 +116,9 @@ module.exports = {
       }
     ]
   },
+  resolveLoader: {
+    modules: [path.resolve(__dirname)]
+  },
   stats: {
     assets: false,
     children: false,
@@ -86,4 +134,14 @@ module.exports = {
     version: false,
     warnings: true
   }
-};
+}).then(console.log, e =>
+{
+  // I would prefer to simply leave the exception unhandled, since we want the
+  // script to end in that case. Unfortunatley though Node.js displays a
+  // deprecation warning if we do:
+  //   "[DEP0018] DeprecationWarning: Unhandled promise rejections are
+  //    deprecated. In the future, promise rejections that are not handled
+  //    will terminate the Node.js process with a non-zero exit code."
+  console.error(e.join("\n"));
+  process.exit(1);
+});