packager Module.js: make transformCode function required

Reviewed By: davidaurelio

Differential Revision: D4147343

fbshipit-source-id: 4c00a5905e698a9d257a632f3b02b63587b4644a

packager/react-packager/src/lib/TransformCache.js

@@ -58,8 +58,8 @@ function getCacheFilePaths(props: {
 
 type CachedResult = {
   code: string,
-  dependencies?: ?Array<string>,
-  dependencyOffsets?: ?Array<number>,
+  dependencies: Array<string>,
+  dependencyOffsets: Array<number>,
   map?: ?{},
 };
 
@@ -205,8 +205,8 @@ function readMetadataFileSync(
 ): ?{
   cachedResultHash: number,
   cachedSourceHash: number,
-  dependencies: ?Array<string>,
-  dependencyOffsets: ?Array<number>,
+  dependencies: Array<string>,
+  dependencyOffsets: Array<number>,
   sourceMap: ?{},
 } {
   const metadataStr = fs.readFileSync(metadataFilePath, 'utf8');
@@ -232,8 +232,8 @@ function readMetadataFileSync(
   if (
     typeof cachedResultHash !== 'number' ||
     typeof cachedSourceHash !== 'number' ||
-    !(dependencies == null || (Array.isArray(dependencies) && dependencies.every(dep => typeof dep === 'string'))) ||
-    !(dependencyOffsets == null || (Array.isArray(dependencyOffsets) && dependencyOffsets.every(offset => typeof offset === 'number'))) ||
+    !(Array.isArray(dependencies) && dependencies.every(dep => typeof dep === 'string')) ||
+    !(Array.isArray(dependencyOffsets) && dependencyOffsets.every(offset => typeof offset === 'number')) ||
     !(sourceMap == null || typeof sourceMap === 'object')
   ) {
     return null;

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

@@ -27,8 +27,8 @@ import type FastFs from './fastfs';
 
 type TransformedCode = {
   code: string,
-  dependencies?: ?Array<string>,
-  dependencyOffsets?: ?Array<number>,
+  dependencies: Array<string>,
+  dependencyOffsets: Array<number>,
   map?: ?{},
 };
 
@@ -225,18 +225,13 @@ class Module {
     transformOptions: mixed,
     callback: (error: ?Error, result: ?TransformedCode) => void,
   ) {
-    const transformCode = this._transformCode;
+    const {_transformCode} = this;
     // AssetModule_DEPRECATED doesn't provide transformCode, but these should
     // never be transformed anyway.
-    invariant(transformCode != null, 'missing code transform funtion');
+    invariant(_transformCode != null, 'missing code transform funtion');
     this._readSourceCode().then(sourceCode => {
-      if (!transformCode) {
-        return callback(null, {code: sourceCode});
-      }
-      const codePromise = transformCode(this, sourceCode, transformOptions);
-      return codePromise.then(freshResult => {
-        callback(undefined, freshResult);
-      });
+      return _transformCode(this, sourceCode, transformOptions)
+        .then(freshResult => callback(undefined, freshResult));
     }, callback);
   }
 

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

@@ -69,6 +69,9 @@ describe('Module', () => {
       options: {
         cacheTransformResults: true,
       },
+      transformCode: (module, sourceCode, transformOptions) => {
+        return Promise.resolve({code: sourceCode});
+      },
       ...options,
       cache,
       fastfs,