feat(napi/transformer): add runtime helper mode (#7727)

part of #7599

crates/oxc_transformer/src/lib.rs

@@ -51,7 +51,7 @@ use regexp::RegExp;
 use typescript::TypeScript;
 
 pub use crate::{
-    common::helper_loader::HelperLoaderMode,
+    common::helper_loader::{HelperLoaderMode, HelperLoaderOptions},
     compiler_assumptions::CompilerAssumptions,
     es2015::{ArrowFunctionsOptions, ES2015Options},
     jsx::{JsxOptions, JsxRuntime, ReactRefreshOptions},

napi/transform/index.d.ts

@@ -38,6 +38,34 @@ export interface Es2015Options {
   arrowFunction?: ArrowFunctionsOptions
 }
 
+export declare const enum HelperMode {
+  /**
+   * Runtime mode (default): Helper functions are imported from a runtime package.
+   *
+   * Example:
+   *
+   * ```js
+   * import helperName from "@babel/runtime/helpers/helperName";
+   * helperName(...arguments);
+   * ```
+   */
+  Runtime = 'Runtime',
+  /**
+   * External mode: Helper functions are accessed from a global `babelHelpers` object.
+   *
+   * Example:
+   *
+   * ```js
+   * babelHelpers.helperName(...arguments);
+   * ```
+   */
+  External = 'External'
+}
+
+export interface Helpers {
+  mode?: HelperMode
+}
+
 /** TypeScript Isolated Declarations for Standalone DTS Emit */
 export declare function isolatedDeclaration(filename: string, sourceText: string, options?: IsolatedDeclarationsOptions | undefined | null): IsolatedDeclarationsResult
 
@@ -247,6 +275,8 @@ export interface TransformOptions {
    * @see [esbuild#target](https://esbuild.github.io/api/#target)
    */
   target?: string | Array<string>
+  /** Behaviour for runtime helpers. */
+  helpers?: Helpers
   /** Define Plugin */
   define?: Record<string, string>
   /** Inject Plugin */

napi/transform/index.js

@@ -361,6 +361,7 @@ if (!nativeBinding) {
   throw new Error(`Failed to load native binding`)
 }
 
+module.exports.HelperMode = nativeBinding.HelperMode
 module.exports.isolatedDeclaration = nativeBinding.isolatedDeclaration
 module.exports.Severity = nativeBinding.Severity
 module.exports.transform = nativeBinding.transform

napi/transform/src/transformer.rs

@@ -12,8 +12,8 @@ use oxc::{
     diagnostics::OxcDiagnostic,
     span::SourceType,
     transformer::{
-        EnvOptions, InjectGlobalVariablesConfig, InjectImport, JsxRuntime,
-        ReplaceGlobalDefinesConfig, RewriteExtensionsMode,
+        EnvOptions, HelperLoaderMode, HelperLoaderOptions, InjectGlobalVariablesConfig,
+        InjectImport, JsxRuntime, ReplaceGlobalDefinesConfig, RewriteExtensionsMode,
     },
     CompilerInterface,
 };
@@ -107,6 +107,9 @@ pub struct TransformOptions {
     /// @see [esbuild#target](https://esbuild.github.io/api/#target)
     pub target: Option<Either<String, Vec<String>>>,
 
+    /// Behaviour for runtime helpers.
+    pub helpers: Option<Helpers>,
+
     /// Define Plugin
     #[napi(ts_type = "Record<string, string>")]
     pub define: Option<FxHashMap<String, String>>,
@@ -134,7 +137,9 @@ impl TryFrom<TransformOptions> for oxc::transformer::TransformOptions {
                 .unwrap_or_default(),
             jsx: options.jsx.map(Into::into).unwrap_or_default(),
             env,
-            ..Self::default()
+            helper_loader: options
+                .helpers
+                .map_or_else(HelperLoaderOptions::default, HelperLoaderOptions::from),
         })
     }
 }
@@ -393,6 +398,53 @@ impl From<Es2015Options> for oxc::transformer::ES2015Options {
     }
 }
 
+#[napi(object)]
+#[derive(Default)]
+pub struct Helpers {
+    pub mode: Option<HelperMode>,
+}
+
+#[derive(Default, Clone, Copy)]
+#[napi(string_enum)]
+pub enum HelperMode {
+    /// Runtime mode (default): Helper functions are imported from a runtime package.
+    ///
+    /// Example:
+    ///
+    /// ```js
+    /// import helperName from "@babel/runtime/helpers/helperName";
+    /// helperName(...arguments);
+    /// ```
+    #[default]
+    Runtime,
+    /// External mode: Helper functions are accessed from a global `babelHelpers` object.
+    ///
+    /// Example:
+    ///
+    /// ```js
+    /// babelHelpers.helperName(...arguments);
+    /// ```
+    External,
+}
+
+impl From<Helpers> for HelperLoaderOptions {
+    fn from(value: Helpers) -> Self {
+        Self {
+            mode: value.mode.map(HelperLoaderMode::from).unwrap_or_default(),
+            ..HelperLoaderOptions::default()
+        }
+    }
+}
+
+impl From<HelperMode> for HelperLoaderMode {
+    fn from(value: HelperMode) -> Self {
+        match value {
+            HelperMode::Runtime => Self::Runtime,
+            HelperMode::External => Self::External,
+        }
+    }
+}
+
 #[derive(Default)]
 struct Compiler {
     transform_options: oxc::transformer::TransformOptions,

napi/transform/test/transform.test.ts

@@ -1,6 +1,6 @@
 import { assert, describe, it, test } from 'vitest';
 
-import { transform } from '../index';
+import { HelperMode, transform } from '../index';
 
 describe('simple', () => {
   const code = 'export class A<T> {}';
@@ -92,6 +92,22 @@ describe('target', () => {
   });
 });
 
+describe('helpers', () => {
+  const data: Array<[HelperMode, string]> = [
+    [HelperMode.External, 'babelHelpers.objectSpread2({}, x);\n'],
+    [HelperMode.Runtime, 'import _objectSpread from "@babel/runtime/helpers/objectSpread2";\n_objectSpread({}, x);\n'],
+  ];
+
+  test.each(data)('%s', (mode, expected) => {
+    const code = `({ ...x })`;
+    const ret = transform('test.js', code, {
+      target: 'es2015',
+      helpers: { mode },
+    });
+    assert.equal(ret.code, expected);
+  });
+});
+
 describe('modules', () => {
   it('should transform export = and import ', () => {
     const code = `