From 0d19a1e2232e4079713b5e42ca46fefcbcc93acd Mon Sep 17 00:00:00 2001
From: Sebastian Silbermann <silbermann.sebastian@gmail.com>
Date: Thu, 28 Feb 2019 12:42:01 +0100
Subject: [PATCH] add error message if bot keep- and out-file-extension is used

---
 packages/babel-cli/src/babel/options.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/packages/babel-cli/src/babel/options.js b/packages/babel-cli/src/babel/options.js
index dfdb604d90e2..7e58b7b0d5ff 100644
--- a/packages/babel-cli/src/babel/options.js
+++ b/packages/babel-cli/src/babel/options.js
@@ -215,6 +215,12 @@ export default function parseArgv(args: Array<string>) {
     );
   }
 
+  if (commander.keepFileExtension && commander.outFileExtension) {
+    errors.push(
+      "--out-file-extension cannot be used with --keep-file-extension",
+    );
+  }
+
   if (errors.length) {
     console.error("babel:");
     errors.forEach(function(e) {