feat(oxfmt): use prettier directly and bundle prettier (#15544)

`@prettier/sync` is the synchronous version of `prettier`, which uses the `Worker` to hack it and make it synchronous.

Everything worked fine before we wanted to bundle them together. However, it hangs when they are bundled. I haven't found the reason why it hangs. Anyway, I don't think `@prettier/sync` is a good choice because it is not `real` synchronous, which sacrifices some performance to make it available.

Note: I am not familiar with NAPI, so I'm not sure whether the API is used correctly.

Author: Dunqing

apps/oxfmt/package.json

@@ -20,8 +20,7 @@
     "node": "^20.19.0 || >=22.12.0"
   },
   "dependencies": {
-    "prettier": "3.6.2",
-    "@prettier/sync": "0.6.1"
+    "prettier": "3.6.2"
   },
   "devDependencies": {
     "@types/node": "catalog:",

apps/oxfmt/src-js/embedded.ts

@@ -1,4 +1,4 @@
-import prettier from '@prettier/sync';
+import prettier from 'prettier';
 
 // Map template tag names to Prettier parsers
 const TAG_TO_PARSER: Record<string, string> = {
@@ -25,27 +25,22 @@ const TAG_TO_PARSER: Record<string, string> = {
  * @param code - The code to format
  * @returns Formatted code
  */
-export function formatEmbeddedCode(tagName: string, code: string): string {
+export async function formatEmbeddedCode(tagName: string, code: string): Promise<string> {
   const parser = TAG_TO_PARSER[tagName];
 
   if (!parser) {
     // Unknown tag, return original code
     return code;
   }
 
-  try {
-    const formatted = prettier.format(code, {
+  return prettier
+    .format(code, {
       parser,
       printWidth: 80,
       tabWidth: 2,
       semi: true,
       singleQuote: false,
-    });
-
-    // Remove trailing newline that Prettier adds
-    return formatted.trimEnd();
-  } catch {
-    // If Prettier fails to format, return original code
-    return code;
-  }
+    })
+    .then((formatted) => formatted.trimEnd())
+    .catch(() => code);
 }

apps/oxfmt/src/prettier_plugins/external_formatter.rs

@@ -2,7 +2,7 @@ use std::sync::Arc;
 
 use napi::{
     Status,
-    bindgen_prelude::FnArgs,
+    bindgen_prelude::{FnArgs, Promise, block_on},
     threadsafe_function::{ThreadsafeFunction, ThreadsafeFunctionCallMode},
 };
 use oxc_formatter::EmbeddedFormatterCallback;
@@ -13,7 +13,7 @@ pub type JsFormatEmbeddedCb = ThreadsafeFunction<
     // Input arguments
     FnArgs<(String, String)>, // (tag_name, code) as separate arguments
     // Return type (what JS function returns)
-    String,
+    Promise<String>,
     // Arguments (repeated)
     FnArgs<(String, String)>,
     // Error status
@@ -65,7 +65,7 @@ pub fn wrap_format_embedded(cb: JsFormatEmbeddedCb) -> EmbeddedFormatterCallback
         let status = cb.call_with_return_value(
             FnArgs::from((tag_name_str.clone(), code_str)),
             ThreadsafeFunctionCallMode::Blocking,
-            move |result: Result<String, napi::Error>, _env| {
+            move |result: Result<Promise<String>, napi::Error>, _env| {
                 // Send the result through the channel
                 let _ = tx.send(result);
                 Ok(())
@@ -80,7 +80,9 @@ pub fn wrap_format_embedded(cb: JsFormatEmbeddedCb) -> EmbeddedFormatterCallback
 
         // Wait for the result from the channel
         match rx.recv() {
-            Ok(Ok(formatted)) => Ok(formatted),
+            Ok(Ok(promise)) => block_on(promise).map_err(|e| {
+                format!("JS formatter promise rejected for tag '{tag_name_str}': {e}")
+            }),
             Ok(Err(e)) => Err(format!("JS formatter failed for tag '{tag_name_str}': {e}")),
             Err(_) => {
                 Err(format!("Failed to receive result from JS formatter for tag '{tag_name_str}'"))

apps/oxfmt/src/run.rs

@@ -24,11 +24,12 @@ use crate::{
 #[allow(clippy::trailing_empty_array, clippy::unused_async)] // https://github.com/napi-rs/napi-rs/issues/2758
 #[napi]
 pub async fn format(args: Vec<String>, format_embedded_cb: JsFormatEmbeddedCb) -> bool {
-    format_impl(&args, format_embedded_cb).report() == ExitCode::SUCCESS
+    format_impl(args, format_embedded_cb).report() == ExitCode::SUCCESS
 }
 
 /// Run the formatter.
-fn format_impl(args: &[String], format_embedded_cb: JsFormatEmbeddedCb) -> CliRunResult {
+#[expect(clippy::needless_pass_by_value)]
+fn format_impl(args: Vec<String>, format_embedded_cb: JsFormatEmbeddedCb) -> CliRunResult {
     init_tracing();
     init_miette();
 

apps/oxfmt/tsdown.config.ts

@@ -9,4 +9,5 @@ export default defineConfig({
   clean: true,
   outDir: 'dist',
   shims: false,
+  noExternal: ['prettier'],
 });

npm/oxfmt/package.json

@@ -24,10 +24,6 @@
   "engines": {
     "node": "^20.19.0 || >=22.12.0"
   },
-  "dependencies": {
-    "prettier": "3.6.2",
-    "@prettier/sync": "0.6.1"
-  },
   "files": [
     "bin/oxfmt",
     "configuration_schema.json",