Send HMR updates only for files on the bundle

Summary:
public

Compute the dependencies of the bundle entry file just before sending HMR updates. In case the file that was changed doesn't belong to the bundle bail.

Reviewed By: vjeux

Differential Revision: D2793736

fb-gh-sync-id: f858e71b0dd5fe4f5b2307a22c6cef627eb66a22

react-packager/src/Bundler/index.js

@@ -310,6 +310,10 @@ class Bundler {
     this._transformer.invalidateFile(filePath);
   }
 
+  getShallowDependencies(entryFile) {
+    return this._resolver.getShallowDependencies(entryFile);
+  }
+
   getDependencies(main, isDev, platform) {
     return this._resolver.getDependencies(main, { dev: isDev, platform });
   }

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

@@ -133,6 +133,14 @@ class DependencyGraph {
     return this._loading;
   }
 
+  /**
+   * Returns a promise with the direct dependencies the module associated to
+   * the given entryPath has.
+   */
+  getShallowDependencies(entryPath) {
+    return this._moduleCache.getModule(entryPath).getDependencies();
+  }
+
   getDependencies(entryPath, platform) {
     return this.load().then(() => {
       platform = this._getRequestPlatform(entryPath, platform);

react-packager/src/Resolver/index.js

@@ -99,6 +99,10 @@ class Resolver {
     this._polyfillModuleNames = opts.polyfillModuleNames || [];
   }
 
+  getShallowDependencies(entryFile) {
+    return this._depGraph.getShallowDependencies(entryFile);
+  }
+
   getDependencies(main, options) {
     const opts = getDependenciesValidateOpts(options);
 

react-packager/src/Server/index.js

@@ -246,6 +246,10 @@ class Server {
     });
   }
 
+  getShallowDependencies(entryFile) {
+    return this._bundler.getShallowDependencies(entryFile);
+  }
+
   getDependencies(options) {
     return Promise.resolve().then(() => {
       if (!options.platform) {