Handle transform problems correctly

Summary: This fixes a piece of promise code that didn’t handle nested rejections. This caused the packager not to recover from transform errors, as the server was waiting for an in-limbo promise forever.

Reviewed By: cpojer

Differential Revision: D4207138

fbshipit-source-id: 8e94ddebd033073f90b79b1c4820c09ac98a4932

packager/react-packager/src/node-haste/Module.js

@@ -223,19 +223,24 @@ class Module {
     // never be transformed anyway.
     invariant(_transformCode != null, 'missing code transform funtion');
     invariant(_transformCacheKey != null, 'missing cache key');
-    this._readSourceCode().then(sourceCode => {
+    this._readSourceCode()
-      return _transformCode(this, sourceCode, transformOptions)
+      .then(sourceCode =>
-        .then(freshResult => {
+        _transformCode(this, sourceCode, transformOptions)
-          TransformCache.writeSync({
+          .then(freshResult => {
-            filePath: this.path,
+            TransformCache.writeSync({
-            sourceCode,
+              filePath: this.path,
-            transformCacheKey: _transformCacheKey,
+              sourceCode,
-            transformOptions,
+              transformCacheKey: _transformCacheKey,
-            result: freshResult,
+              transformOptions,
-          });
+              result: freshResult,
-          callback(undefined, freshResult);
+            });
-        });
+            return freshResult;
-    }, callback);
+          })
+      )
+      .then(
+        freshResult => process.nextTick(callback, null, freshResult),
+        error => process.nextTick(callback, error),
+      );
   }
 
   /**