feat(transform-react): expose TypeScript transform options

Original PR: #26899

Closes #26864

napi/transform-react/index.d.ts

@@ -360,6 +360,12 @@ export interface TransformOptions {
    * @see <https://oxc.rs/docs/guide/usage/transformer/jsx>
    */
   jsx?: 'preserve' | JsxOptions
+  /**
+   * Configure how Typescript is transformed.
+   *
+   * @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+   */
+  typescript?: TypeScriptOptions
   /**
    * Configure React Compiler, or disable it with `false`.
    *
@@ -397,3 +403,26 @@ export interface TransformResult {
  * removed and configured JSX transforms run afterwards.
  */
 export declare function transformSync(filename: string, sourceText: string, options?: TransformOptions | undefined | null): TransformResult
+
+/**
+ * Configure how Typescript is transformed.
+ *
+ * @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+ */
+export interface TypeScriptOptions {
+  /**
+   * Inlines const enum values and removes the declaration.
+   *
+   * @default false
+   */
+  optimizeConstEnums?: boolean
+  /**
+   * Inlines regular (non-const) enum member accesses when all members
+   * satisfy const enum constraints (i.e., their values are statically evaluable).
+   * Non-exported enum declarations are also removed when all members are
+   * evaluable and no references to the enum as a runtime value exist.
+   *
+   * @default false
+   */
+  optimizeEnums?: boolean
+}

napi/transform-react/src/options.rs

@@ -36,6 +36,12 @@ pub struct TransformOptions {
     #[napi(ts_type = "'preserve' | JsxOptions")]
     pub jsx: Option<Either<String, JsxOptions>>,
 
+    /// Configure how Typescript is transformed.
+    ///
+    /// @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+    #[napi(ts_type = "TypeScriptOptions")]
+    pub typescript: Option<TypeScriptOptions>,
+
     /// Configure React Compiler, or disable it with `false`.
     ///
     /// @default true
@@ -188,6 +194,26 @@ pub struct JsxOptions {
     pub refresh: Option<Either<bool, ReactRefreshOptions>>,
 }
 
+/// Configure how Typescript is transformed.
+///
+/// @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+#[napi(object)]
+#[derive(Debug)]
+pub struct TypeScriptOptions {
+    /// Inlines const enum values and removes the declaration.
+    ///
+    /// @default false
+    pub optimize_const_enums: Option<bool>,
+
+    /// Inlines regular (non-const) enum member accesses when all members
+    /// satisfy const enum constraints (i.e., their values are statically evaluable).
+    /// Non-exported enum declarations are also removed when all members are
+    /// evaluable and no references to the enum as a runtime value exist.
+    ///
+    /// @default false
+    pub optimize_enums: Option<bool>,
+}
+
 /// React Fast Refresh options.
 #[napi(object)]
 #[derive(Debug)]
@@ -313,10 +339,16 @@ impl TransformOptions {
             Some(Either::B(options)) => oxc::transformer::JsxOptions::from(options),
         };
 
+        let typescript: oxc::transformer::TypeScriptOptions = match self.typescript {
+            None => oxc::transformer::TypeScriptOptions::default(),
+            Some(options) => oxc::transformer::TypeScriptOptions::from(options),
+        };
+
         Ok((
             react_compiler,
             oxc::transformer::TransformOptions {
                 jsx,
+                typescript,
                 ..oxc::transformer::TransformOptions::default()
             },
         ))
@@ -426,6 +458,19 @@ impl From<JsxOptions> for oxc::transformer::JsxOptions {
     }
 }
 
+impl From<TypeScriptOptions> for oxc::transformer::TypeScriptOptions {
+    fn from(options: TypeScriptOptions) -> Self {
+        let defaults = Self::default();
+        Self {
+            optimize_const_enums: options
+                .optimize_const_enums
+                .unwrap_or(defaults.optimize_const_enums),
+            optimize_enums: options.optimize_enums.unwrap_or(defaults.optimize_enums),
+            ..defaults
+        }
+    }
+}
+
 impl From<ReactRefreshOptions> for oxc::transformer::ReactRefreshOptions {
     fn from(options: ReactRefreshOptions) -> Self {
         let defaults = Self::default();

napi/transform-react/test/fixtures.test.ts

@@ -0,0 +1,28 @@
+import { existsSync, readdirSync, readFileSync } from "node:fs";
+import { join } from "node:path";
+
+import { describe, expect, it } from "vitest";
+
+import { transformSync, type TransformOptions, type TransformResult } from "../index";
+
+const fixturesDir = join(import.meta.dirname, "fixtures");
+const fixtures = readdirSync(fixturesDir).sort();
+
+function render(result: TransformResult): string {
+  const errors = result.errors.map((error) => `${error.severity}: ${error.message}`).join("\n");
+  return `## Code\n\n${result.code}\n## Errors\n\n${errors || "(none)"}\n\n## Fatal\n\n${result.fatal}\n`;
+}
+
+describe("fixtures", () => {
+  it.each(fixtures)("%s", async (name) => {
+    const dir = join(fixturesDir, name);
+    const input = readdirSync(dir).find((file) => file.startsWith("input."));
+    if (input === undefined) throw new Error(`${name} has no input file`);
+    const optionsPath = join(dir, "options.json");
+    const options: TransformOptions = existsSync(optionsPath)
+      ? JSON.parse(readFileSync(optionsPath, "utf8"))
+      : {};
+    const result = transformSync(input, readFileSync(join(dir, input), "utf8"), options);
+    await expect(render(result)).toMatchFileSnapshot(join(dir, "output.snap"));
+  });
+});

napi/transform-react/test/fixtures/typescript-enums-default/input.tsx

@@ -0,0 +1,16 @@
+enum Direction {
+  Up = 1,
+  Down = 2,
+}
+
+const enum Status {
+  Active = "active",
+}
+
+export function App() {
+  return (
+    <div>
+      {Direction.Up}:{Status.Active}
+    </div>
+  );
+}

napi/transform-react/test/fixtures/typescript-enums-default/options.json

@@ -0,0 +1,3 @@
+{
+  "reactCompiler": false
+}

napi/transform-react/test/fixtures/typescript-enums-default/output.snap

@@ -0,0 +1,27 @@
+## Code
+
+import { jsxs as _jsxs } from "react/jsx-runtime";
+var Direction = /* @__PURE__ */ function(Direction) {
+	Direction[Direction["Up"] = 1] = "Up";
+	Direction[Direction["Down"] = 2] = "Down";
+	return Direction;
+}(Direction || {});
+var Status = /* @__PURE__ */ function(Status) {
+	Status["Active"] = "active";
+	return Status;
+}(Status || {});
+export function App() {
+	return /* @__PURE__ */ _jsxs("div", { children: [
+		Direction.Up,
+		":",
+		Status.Active
+	] });
+}
+
+## Errors
+
+(none)
+
+## Fatal
+
+false

napi/transform-react/test/fixtures/typescript-optimize-const-enums/input.tsx

@@ -0,0 +1,16 @@
+enum Direction {
+  Up = 1,
+  Down = 2,
+}
+
+const enum Status {
+  Active = "active",
+}
+
+export function App() {
+  return (
+    <div>
+      {Direction.Up}:{Status.Active}
+    </div>
+  );
+}

napi/transform-react/test/fixtures/typescript-optimize-const-enums/options.json

@@ -0,0 +1,7 @@
+{
+  "reactCompiler": false,
+  "typescript": {
+    "optimizeConstEnums": true,
+    "optimizeEnums": false
+  }
+}

napi/transform-react/test/fixtures/typescript-optimize-const-enums/output.snap

@@ -0,0 +1,23 @@
+## Code
+
+import { jsxs as _jsxs } from "react/jsx-runtime";
+var Direction = /* @__PURE__ */ function(Direction) {
+	Direction[Direction["Up"] = 1] = "Up";
+	Direction[Direction["Down"] = 2] = "Down";
+	return Direction;
+}(Direction || {});
+export function App() {
+	return /* @__PURE__ */ _jsxs("div", { children: [
+		Direction.Up,
+		":",
+		"active"
+	] });
+}
+
+## Errors
+
+(none)
+
+## Fatal
+
+false

napi/transform-react/test/fixtures/typescript-optimize-enums-with-react-compiler/input.tsx

@@ -0,0 +1,16 @@
+enum Direction {
+  Up = 1,
+  Down = 2,
+}
+
+const enum Status {
+  Active = "active",
+}
+
+export function App() {
+  return (
+    <div>
+      {Direction.Up}:{Status.Active}
+    </div>
+  );
+}

napi/transform-react/test/fixtures/typescript-optimize-enums-with-react-compiler/options.json

@@ -0,0 +1,6 @@
+{
+  "typescript": {
+    "optimizeConstEnums": true,
+    "optimizeEnums": true
+  }
+}

napi/transform-react/test/fixtures/typescript-optimize-enums-with-react-compiler/output.snap

@@ -0,0 +1,27 @@
+## Code
+
+import { c as _c } from "react/compiler-runtime";
+import { jsxs as _jsxs } from "react/jsx-runtime";
+export function App() {
+	const $ = _c(1);
+	let t0;
+	if ($[0] === Symbol.for("react.memo_cache_sentinel")) {
+		t0 = /* @__PURE__ */ _jsxs("div", { children: [
+			1,
+			":",
+			"active"
+		] });
+		$[0] = t0;
+	} else {
+		t0 = $[0];
+	}
+	return t0;
+}
+
+## Errors
+
+(none)
+
+## Fatal
+
+false

napi/transform-react/test/fixtures/typescript-optimize-enums/input.tsx

@@ -0,0 +1,16 @@
+enum Direction {
+  Up = 1,
+  Down = 2,
+}
+
+const enum Status {
+  Active = "active",
+}
+
+export function App() {
+  return (
+    <div>
+      {Direction.Up}:{Status.Active}
+    </div>
+  );
+}

napi/transform-react/test/fixtures/typescript-optimize-enums/options.json

@@ -0,0 +1,7 @@
+{
+  "reactCompiler": false,
+  "typescript": {
+    "optimizeConstEnums": true,
+    "optimizeEnums": true
+  }
+}

napi/transform-react/test/fixtures/typescript-optimize-enums/output.snap

@@ -0,0 +1,18 @@
+## Code
+
+import { jsxs as _jsxs } from "react/jsx-runtime";
+export function App() {
+	return /* @__PURE__ */ _jsxs("div", { children: [
+		1,
+		":",
+		"active"
+	] });
+}
+
+## Errors
+
+(none)
+
+## Fatal
+
+false

napi/transform-react/transform-react.wasi.d.cts

@@ -355,6 +355,12 @@ export interface TransformOptions {
    * @see <https://oxc.rs/docs/guide/usage/transformer/jsx>
    */
   jsx?: 'preserve' | JsxOptions
+  /**
+   * Configure how Typescript is transformed.
+   *
+   * @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+   */
+  typescript?: TypeScriptOptions
   /**
    * Configure React Compiler, or disable it with `false`.
    *
@@ -392,3 +398,26 @@ export interface TransformResult {
  * removed and configured JSX transforms run afterwards.
  */
 export declare function transformSync(filename: string, sourceText: string, options?: TransformOptions | undefined | null): TransformResult
+
+/**
+ * Configure how Typescript is transformed.
+ *
+ * @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+ */
+export interface TypeScriptOptions {
+  /**
+   * Inlines const enum values and removes the declaration.
+   *
+   * @default false
+   */
+  optimizeConstEnums?: boolean
+  /**
+   * Inlines regular (non-const) enum member accesses when all members
+   * satisfy const enum constraints (i.e., their values are statically evaluable).
+   * Non-exported enum declarations are also removed when all members are
+   * evaluable and no references to the enum as a runtime value exist.
+   *
+   * @default false
+   */
+  optimizeEnums?: boolean
+}

napi/transform-react/transform-react.wasip1.d.cts

@@ -355,6 +355,12 @@ export interface TransformOptions {
    * @see <https://oxc.rs/docs/guide/usage/transformer/jsx>
    */
   jsx?: 'preserve' | JsxOptions
+  /**
+   * Configure how Typescript is transformed.
+   *
+   * @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+   */
+  typescript?: TypeScriptOptions
   /**
    * Configure React Compiler, or disable it with `false`.
    *
@@ -392,3 +398,26 @@ export interface TransformResult {
  * removed and configured JSX transforms run afterwards.
  */
 export declare function transformSync(filename: string, sourceText: string, options?: TransformOptions | undefined | null): TransformResult
+
+/**
+ * Configure how Typescript is transformed.
+ *
+ * @see <https://oxc.rs/docs/guide/usage/transformer/typescript>
+ */
+export interface TypeScriptOptions {
+  /**
+   * Inlines const enum values and removes the declaration.
+   *
+   * @default false
+   */
+  optimizeConstEnums?: boolean
+  /**
+   * Inlines regular (non-const) enum member accesses when all members
+   * satisfy const enum constraints (i.e., their values are statically evaluable).
+   * Non-exported enum declarations are also removed when all members are
+   * evaluable and no references to the enum as a runtime value exist.
+   *
+   * @default false
+   */
+  optimizeEnums?: boolean
+}