From e89c93f4f76bcd2030b30750a08dfec2cb2b3f02 Mon Sep 17 00:00:00 2001
From: Simen Bekkhus <simenb@folio.no>
Date: Thu, 7 Apr 2022 08:23:50 -0700
Subject: [PATCH] fix(preprocessor): return object, not just code (#33576)

Summary:
Jest 28 will error if only a string is returned from a transfomer, it needs to be an object of `{code: string, map?: object}`. Returning an object has been supported since https://github.com/facebook/jest/pull/2290, released in Jest v20.

## Changelog

<!-- Help reviewers and the release process by writing your own changelog entry. For an example, see:
https://github.com/facebook/react-native/wiki/Changelog
-->

[Internal] [Fixed] - Return object from Jest preprocessor

Pull Request resolved: https://github.com/facebook/react-native/pull/33576

Test Plan: Green CI?

Reviewed By: motiz88

Differential Revision: D35426748

Pulled By: robhogan

fbshipit-source-id: 3edb79b62b2d34274be192061817d3fcd8a7ba17
---
 jest/preprocessor_DO_NOT_USE.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/jest/preprocessor_DO_NOT_USE.js b/jest/preprocessor_DO_NOT_USE.js
index b4fae006b41fd5..09c0140f033f39 100644
--- a/jest/preprocessor_DO_NOT_USE.js
+++ b/jest/preprocessor_DO_NOT_USE.js
@@ -30,7 +30,7 @@ babelRegisterOnly([]);
 
 const transformer = require('metro-react-native-babel-transformer');
 module.exports = {
-  process(src /*: string */, file /*: string */) /*: string */ {
+  process(src /*: string */, file /*: string */) /*: {code: string, ...} */ {
     if (nodeFiles.test(file)) {
       // node specific transforms only
       return babelTransformSync(src, {
@@ -38,7 +38,7 @@ module.exports = {
         sourceType: 'script',
         ...nodeOptions,
         ast: false,
-      }).code;
+      });
     }
 
     const {ast} = transformer.transform({
@@ -111,7 +111,7 @@ module.exports = {
         sourceMaps: true,
       },
       src,
-    ).code;
+    );
   },
 
   getCacheKey: (createCacheKeyFunction([