From dfab78e840bdc099354f7a419c440232599b06dc Mon Sep 17 00:00:00 2001
From: EGOIST <0x142857@gmail.com>
Date: Fri, 10 Dec 2021 16:48:40 +0800
Subject: [PATCH] chore: tweaks

---
 src/plugins/es5.ts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/plugins/es5.ts b/src/plugins/es5.ts
index 4d1c263c..756e1abb 100644
--- a/src/plugins/es5.ts
+++ b/src/plugins/es5.ts
@@ -1,3 +1,4 @@
+import { PrettyError } from '../errors'
 import { Plugin } from '../plugin'
 import { localRequire } from '../utils'
 
@@ -18,6 +19,13 @@ export const es5 = (): Plugin => {
         return
       }
       const swc: typeof import('@swc/core') = localRequire('@swc/core')
+
+      if (!swc) {
+        throw new PrettyError(
+          '@swc/core is required for es5 target. Please install it with `npm install @swc/core -D`'
+        )
+      }
+
       const result = await swc.transform(code, {
         filename: info.path,
         sourceMaps: this.options.sourcemap,