[Packager] Support null modules

Author: aleclarson

packager/react-packager/src/Bundler/index.js

@@ -181,6 +181,19 @@ class Bundler {
   }
 
   _transformModule(bundle, response, module, platform = null) {
+
+    if (module.isNull) {
+      return this._resolver
+        .wrapModule(response, module)
+        .then(function(code) {
+          return new ModuleTransport({
+            code: code,
+            sourceCode: module.code,
+            sourcePath: module.path,
+          });
+        });
+    }
+
     let transform;
 
     if (module.isAsset_DEPRECATED()) {

packager/react-packager/src/DependencyResolver/DependencyGraph/ResolutionRequest.js

@@ -59,9 +59,16 @@ class ResolutionRequest {
       return Q(asset_DEPRECATED);
     }
 
-    return this._redirectRequire(fromModule, toModuleName)
+    return Q.all([
+      toModuleName,
+      this._redirectRequire(fromModule, toModuleName)
+    ])
 
-    .then((toModuleName) => {
+    .then(([oldModuleName, toModuleName]) => {
+
+      if (toModuleName === null) {
+        return this._getNullModule(oldModuleName);
+      }
 
       var promise = Q.reject();
 
@@ -356,6 +363,23 @@ class ResolutionRequest {
     const error = new Error('Failed to resolve "' + toModuleName + '" from "' + fromModule.path + '"');
     log.error(error, { simple: true, exit: false });
   }
+
+  _getNullModule(modulePath) {
+    return Q.try(() => {
+      const isNew = this._moduleCache._moduleCache[modulePath] == null;
+      const module = this._moduleCache.getModule(modulePath);
+      if (isNew) {
+        module.isNull = true;
+        module.code = 'module.exports = null;';
+        module.isHaste = () => false;
+        module.isPolyfill = () => false;
+        module.getName = () => Q(modulePath);
+        module.getPackage = () => null;
+        module.getDependencies = () => Q([]);
+      }
+      return module;
+    });
+  }
 }
 
 

packager/react-packager/src/DependencyResolver/Package.js

@@ -69,7 +69,10 @@ class Package {
       const redirect = browser[relPath] ||
               browser[relPath + '.js'] ||
               browser[relPath + '.json'];
-      if (redirect) {
+      if (redirect === false) {
+        return null;
+      }
+      if (typeof redirect === 'string') {
         return path.join(
           this.root,
           redirect

packager/react-packager/src/DependencyResolver/index.js

@@ -126,6 +126,14 @@ HasteDependencyResolver.prototype.wrapModule = function(resolutionResponse, modu
       return Q(code);
     }
 
+    if (module.isNull) {
+      return defineModuleCode({
+        moduleName: module.id,
+        deps: [],
+        code: module.code,
+      });
+    }
+
     const resolvedDeps = Object.create(null);
     const resolvedDepsArr = [];