Allow custom platforms for the RN Packager on a per-project basis

Reviewed By: cpojer

Differential Revision: D4255979

fbshipit-source-id: bf900b67ee30e2f994e96c9a6103ed2e53a87f88

local-cli/default.config.js

@@ -34,6 +34,15 @@ var config = {
     return [];
   },
 
+  /**
+   * Specify any additional platforms to be used by the packager.
+   * For example, if you want to add a "custom" platform, and use modules
+   * ending in .custom.js, you would return ['custom'] here.
+   */
+  getPlatforms() {
+    return [];
+  },
+
   /**
    * Returns a regular expression for modules that should be ignored by the
    * packager on a given platform.

local-cli/server/runServer.js

@@ -16,6 +16,7 @@ const connect = require('connect');
 const copyToClipBoardMiddleware = require('./middleware/copyToClipBoardMiddleware');
 const cpuProfilerMiddleware = require('./middleware/cpuProfilerMiddleware');
 const defaultAssetExts = require('../../packager/defaults').assetExts;
+const defaultPlatforms = require('../../packager/defaults').platforms;
 const getDevToolsMiddleware = require('./middleware/getDevToolsMiddleware');
 const heapCaptureMiddleware = require('./middleware/heapCaptureMiddleware.js');
 const http = require('http');
@@ -91,6 +92,7 @@ function getPackagerServer(args, config) {
     cacheVersion: '3',
     extraNodeModules: config.extraNodeModules,
     getTransformOptions: config.getTransformOptions,
+    platforms: defaultPlatforms.concat(args.platforms),
     projectRoots: args.projectRoots,
     resetCache: args.resetCache,
     transformModulePath: transformModulePath,

local-cli/server/server.js

@@ -96,6 +96,11 @@ module.exports = {
     description: 'Specify any additional asset extentions to be used by the packager',
     parse: (val) => val.split(','),
     default: (config) => config.getAssetExts(),
+  }, {
+    command: '--platforms [list]',
+    description: 'Specify any additional platforms to be used by the packager',
+    parse: (val) => val.split(','),
+    default: (config) => config.getPlatforms(),
   }, {
     command: '--skipflow',
     description: 'Disable flow checks'