Fix mangleErrorsPlugin not preserving different error types

- Resolved an issue where `mangleErrorsPlugin` did not preserve the original error constructor type. Previously, if a `TypeError` or any other custom error was thrown, the plugin would incorrectly transform it into a generic `Error`.

Author: aryaemami59

packages/toolkit/scripts/mangleErrors.mts

@@ -97,9 +97,15 @@ export const mangleErrorsPlugin = (
       changeInArray = false
     },
     visitor: {
-      ThrowStatement(path, file) {
+      ThrowStatement(path) {
+        if (
+          !('arguments' in path.node.argument) ||
+          !t.isNewExpression(path.node.argument)
+        ) {
+          return
+        }
         const args = path.node.argument.arguments
-        const minify = file.opts.minify
+        const { minify } = options
 
         if (args && args[0]) {
           // Skip running this logic when certain types come up:
@@ -112,11 +118,14 @@ export const mangleErrorsPlugin = (
             path.node.argument.arguments[0].type === 'CallExpression' ||
             path.node.argument.arguments[0].type === 'ObjectExpression' ||
             path.node.argument.arguments[0].type === 'MemberExpression' ||
-            path.node.argument.arguments[0]?.callee?.name === 'HandledError'
+            !t.isExpression(path.node.argument.arguments[0]) ||
+            !t.isIdentifier(path.node.argument.callee)
           ) {
             return
           }
 
+          const errorName = path.node.argument.callee.name
+
           const errorMsgLiteral = evalToString(path.node.argument.arguments[0])
 
           if (errorMsgLiteral.includes('Super expression')) {
@@ -149,13 +158,13 @@ export const mangleErrorsPlugin = (
           if (minify) {
             path.replaceWith(
               t.throwStatement(
-                t.newExpression(t.identifier('Error'), [prodMessage]),
+                t.newExpression(t.identifier(errorName), [prodMessage]),
               ),
             )
           } else {
             path.replaceWith(
               t.throwStatement(
-                t.newExpression(t.identifier('Error'), [
+                t.newExpression(t.identifier(errorName), [
                   t.conditionalExpression(
                     t.binaryExpression(
                       '===',
@@ -181,4 +190,4 @@ export const mangleErrorsPlugin = (
   }
 }
 
-export default mangleErrorsPlugin
+export default mangleErrorsPlugin

packages/toolkit/tsup.config.ts

@@ -6,6 +6,8 @@ import path from 'node:path'
 import { fileURLToPath } from 'node:url'
 import type { Options as TsupOptions } from 'tsup'
 import { defineConfig } from 'tsup'
+import type { MangleErrorsPluginOptions } from './scripts/mangleErrors.mjs'
+import { mangleErrorsPlugin } from './scripts/mangleErrors.mjs'
 
 // No __dirname under Node ESM
 const __filename = fileURLToPath(import.meta.url)
@@ -129,18 +131,28 @@ if (process.env.NODE_ENV === 'production') {
 
 // Extract error strings, replace them with error codes, and write messages to a file
 const mangleErrorsTransform: Plugin = {
-  name: 'mangle-errors-plugin',
+  name: mangleErrorsPlugin.name,
   setup(build) {
-    const { onTransform } = getBuildExtensions(build, 'mangle-errors-plugin')
+    const { onTransform } = getBuildExtensions(build, mangleErrorsPlugin.name)
 
     onTransform({ loaders: ['ts', 'tsx'] }, async (args) => {
       try {
-        const res = babel.transformSync(args.code, {
+        const res = await babel.transformAsync(args.code, {
           parserOpts: {
             plugins: ['typescript', 'jsx'],
           },
-          plugins: [['./scripts/mangleErrors.cjs', { minify: false }]],
-        })!
+          plugins: [
+            [
+              mangleErrorsPlugin,
+              { minify: false } satisfies MangleErrorsPluginOptions,
+            ],
+          ],
+        })
+
+        if (res == null) {
+          throw new Error('Babel transformAsync returned null')
+        }
+
         return {
           code: res.code!,
           map: res.map!,