fix(terser): __filename not defined

CODEOWNERS

@@ -3,3 +3,4 @@
 /packages/babel/ @Andarist
 /packages/image/ @tjenkinson
 /packages/node-resolve/ @tjenkinson
+/packages/terser/ @tada5hi

packages/terser/src/module.ts

@@ -1,12 +1,31 @@
+import { fileURLToPath } from 'url';
+
 import type { NormalizedOutputOptions, RenderedChunk } from 'rollup';
 import { hasOwnProperty, isObject, merge } from 'smob';
 
 import type { Options } from './type';
 import { WorkerPool } from './worker-pool';
 
 export default function terser(options: Options = {}) {
+  let filePath: string | undefined;
+
+  if (typeof __filename !== 'undefined') {
+    filePath = __filename;
+  } else {
+    // @ts-ignore
+    // eslint-disable-next-line no-lonely-if
+    if (typeof import.meta !== 'undefined') {
+      // @ts-ignore
+      filePath = fileURLToPath(import.meta.url);
+    }
+  }
+
+  if (typeof filePath === 'undefined') {
+    throw new Error('File path could not be determined.');
+  }
+
   const workerPool = new WorkerPool({
-    filePath: __filename,
+    filePath,
     maxWorkers: options.maxWorkers
   });