From cc09d52a57dcdae3bfd3ac172b31e0b79565bd88 Mon Sep 17 00:00:00 2001
From: M4rk9696 <nimalan.m@protonmail.com>
Date: Thu, 29 Aug 2019 23:41:28 +0530
Subject: [PATCH] Prevent pirates from transforming folders

---
 packages/jest-transform/src/ScriptTransformer.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/jest-transform/src/ScriptTransformer.ts b/packages/jest-transform/src/ScriptTransformer.ts
index 09f611c67332..029f1d50809f 100644
--- a/packages/jest-transform/src/ScriptTransformer.ts
+++ b/packages/jest-transform/src/ScriptTransformer.ts
@@ -465,6 +465,7 @@ export default class ScriptTransformer {
     this.preloadTransformer(moduleName);
 
     let transforming = false;
+    const ext = path.extname(moduleName);
     const revertHook = addHook(
       (code, filename) => {
         try {
@@ -475,7 +476,7 @@ export default class ScriptTransformer {
         }
       },
       {
-        exts: [path.extname(moduleName)],
+        exts: ext === '' ? ['.js'] : [ext],
         ignoreNodeModules: false,
         matcher: filename => {
           if (transforming) {