diff --git a/packages/ast-utils/package.json b/packages/ast-utils/package.json
index 2cf82aeb..afe16885 100644
--- a/packages/ast-utils/package.json
+++ b/packages/ast-utils/package.json
@@ -23,7 +23,8 @@
     "./reference": "./src/reference.ts",
     "./scope": "./src/scope.ts",
     "./types": "./src/types.ts",
-    "./wrapAstTransformation": "./src/wrapAstTransformation.ts"
+    "./wrapAstTransformation": "./src/wrapAstTransformation.ts",
+    "./wrapStringTransformation": "./src/wrapStringTransformation.ts"
   },
   "files": [
     "dist",
diff --git a/packages/ast-utils/src/wrapStringTransformation.ts b/packages/ast-utils/src/wrapStringTransformation.ts
new file mode 100644
index 00000000..8f0c68d9
--- /dev/null
+++ b/packages/ast-utils/src/wrapStringTransformation.ts
@@ -0,0 +1,18 @@
+import type { Options, Transform } from 'jscodeshift'
+
+export interface StringTransformation<Params = object> {
+    (code: string, params: Params): string | void
+}
+
+export function wrapStringTransformation<Params extends Options>(
+    transformAST: StringTransformation<Params>,
+): Transform {
+    // @ts-expect-error - jscodeshift is not happy
+    const transform: Transform = (file, api, options: Params) => {
+        const code = file.source
+        const result = transformAST(code, options)
+        return result ?? code
+    }
+
+    return transform
+}
diff --git a/packages/unminify/src/transformations/__tests__/un-parameters.spec.ts b/packages/unminify/src/transformations/__tests__/un-parameters.spec.ts
index 3254de29..3c7eb3d2 100644
--- a/packages/unminify/src/transformations/__tests__/un-parameters.spec.ts
+++ b/packages/unminify/src/transformations/__tests__/un-parameters.spec.ts
@@ -208,3 +208,16 @@ function test(a = 1, b) {
 }
 `,
 )
+
+inlineTest('lebab',
+  `
+function test() {
+  console.log(arguments);
+}
+`,
+  `
+function test(...args) {
+  console.log(args);
+}
+`,
+)
diff --git a/packages/unminify/src/transformations/lebab.ts b/packages/unminify/src/transformations/lebab.ts
index 90c14939..900a6c4f 100644
--- a/packages/unminify/src/transformations/lebab.ts
+++ b/packages/unminify/src/transformations/lebab.ts
@@ -1,6 +1,6 @@
-import { wrapAstTransformation } from '@wakaru/ast-utils/wrapAstTransformation'
+import { wrapStringTransformation } from '@wakaru/ast-utils/wrapStringTransformation'
 import { transform } from 'lebab'
-import type { ASTTransformation } from '@wakaru/ast-utils/wrapAstTransformation'
+import type { StringTransformation } from '@wakaru/ast-utils/wrapStringTransformation'
 import type { LebabRule } from 'lebab'
 
 /**
@@ -32,9 +32,8 @@ function transformLebab(input: string, rules: LebabRule[]) {
     return { code, warnings }
 }
 
-export const transformASTWithRules = (rules: LebabRule[]): ASTTransformation => (context) => {
-    const code = context.root.toSource()
+export const transformASTWithRules = (rules: LebabRule[]): StringTransformation => (code) => {
     return transformLebab(code, rules).code
 }
 
-export default wrapAstTransformation(transformASTWithRules(allLebabRules))
+export default wrapStringTransformation(transformASTWithRules(allLebabRules))
diff --git a/packages/unminify/src/transformations/prettier.ts b/packages/unminify/src/transformations/prettier.ts
index 054689db..bab04261 100644
--- a/packages/unminify/src/transformations/prettier.ts
+++ b/packages/unminify/src/transformations/prettier.ts
@@ -1,17 +1,13 @@
-import { wrapAstTransformation } from '@wakaru/ast-utils/wrapAstTransformation'
+import { wrapStringTransformation } from '@wakaru/ast-utils/wrapStringTransformation'
 import babelParser from 'prettier/parser-babel'
 import prettier from 'prettier/standalone'
-import type { ASTTransformation } from '@wakaru/ast-utils/wrapAstTransformation'
 
 /**
  * @url https://prettier.io
  */
-export const transformAST: ASTTransformation = (context) => {
-    const code = context.root.toSource()
+export default wrapStringTransformation((code) => {
     return prettier.format(code, {
         parser: 'babel',
         plugins: [babelParser],
     })
-}
-
-export default wrapAstTransformation(transformAST)
+})
diff --git a/packages/unminify/src/transformations/un-parameters.ts b/packages/unminify/src/transformations/un-parameters.ts
index e9f86156..2ce6c842 100644
--- a/packages/unminify/src/transformations/un-parameters.ts
+++ b/packages/unminify/src/transformations/un-parameters.ts
@@ -79,12 +79,12 @@ export const transformAST: ASTTransformation = (context) => {
             handleBody(j, path)
         })
 
-    transformASTWithRules([
+    return transformASTWithRules([
         // 'default-param',
         // 'destruct-param',
         'arg-spread',
         'arg-rest',
-    ])(context, {})
+    ])(root.toSource({ lineTerminator: '\n' }), {})
 }
 
 /**