diff --git a/src/parser/parse.ts b/src/parser/parse.ts
index c0057b4f5..ad7a96994 100644
--- a/src/parser/parse.ts
+++ b/src/parser/parse.ts
@@ -23,7 +23,7 @@ try {
 const readStdin = async () => {
   const {stdin} = process
   let result
-  if (stdin.isTTY) return result
+  if (stdin.isTTY || stdin.isTTY === undefined) return result
   result = ''
   stdin.setEncoding('utf8')
   for await (const chunk of stdin) {