Re-add the Rolldown optimisations and fix types

Author: timfish

packages/rollup-plugin/src/index.ts

@@ -127,10 +127,12 @@ export function _rollupPluginInternal(userOptions: Options = {}, buildTool: stri
 
   function renderChunk(
     code: string,
-    chunk: { fileName: string; facadeModuleId?: string | null }
+    chunk: { fileName: string; facadeModuleId?: string | null },
+    _?: unknown,
+    meta?: { magicString?: MagicString }
   ): {
     code: string;
-    map: SourceMap;
+    map?: SourceMap;
   } | null {
     if (!isJsFile(chunk.fileName)) {
       return null; // returning null means not modifying the chunk at all
@@ -152,8 +154,7 @@ export function _rollupPluginInternal(userOptions: Options = {}, buildTool: stri
       return null;
     }
 
-    const ms = new MagicString(code, { filename: chunk.fileName });
-
+    const ms = meta?.magicString || new MagicString(code, { filename: chunk.fileName });
     const match = code.match(COMMENT_USE_STRICT_REGEX)?.[0];
 
     if (match) {
@@ -166,6 +167,13 @@ export function _rollupPluginInternal(userOptions: Options = {}, buildTool: stri
       ms.prepend(injectCode.code());
     }
 
+    // Rolldown can pass a native MagicString instance in meta.magicString
+    // https://rolldown.rs/in-depth/native-magic-string#usage-examples
+    if (ms?.constructor?.name === "BindingMagicString") {
+      // Rolldown docs say to return the magic string instance directly in this case
+      return { code: ms as unknown as string };
+    }
+
     return {
       code: ms.toString(),
       map: ms.generateMap({ file: chunk.fileName, hires: "boundary" as unknown as undefined }),
@@ -219,8 +227,8 @@ export function _rollupPluginInternal(userOptions: Options = {}, buildTool: stri
   };
 }
 
-// eslint-disable-next-line @typescript-eslint/explicit-function-return-type
-export function sentryRollupPlugin(userOptions: Options = {}) {
+// eslint-disable-next-line @typescript-eslint/explicit-function-return-type, @typescript-eslint/no-explicit-any
+export function sentryRollupPlugin(userOptions: Options = {}): any {
   // We return an array here so we don't break backwards compatibility with what
   // unplugin used to return
   return [_rollupPluginInternal(userOptions, "rollup")];