diff --git a/src/config.ts b/src/config.ts
index 489cde9..53b2959 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -209,7 +209,7 @@ export async function loadConfigFromFile(
   let resolvedPath: string
   let isESM = false
 
-  if (configFile && /^vite.config.(js)|(ts)|(mjs)|(cjs)$/.test(configFile)) {
+  if (configFile && /^vite.config.(js|ts|mjs|cjs)$/.test(configFile)) {
     throw new Error(`config file cannot be named ${configFile}.`)
   }