fix: cannot resolve path when build with EXTERNAL_PATH (#93)

build.js

@@ -1,5 +1,6 @@
 const fs = require('fs');
 const { buildSync } = require('esbuild');
+const path = require('path/posix')
 
 const { EXTERNAL_PATH } = process.env;
 const MINIFY = !EXTERNAL_PATH;
@@ -22,7 +23,7 @@ buildSync({
   },
   define: EXTERNAL_PATH ? {
     WASM_BINARY: 'undefined',
-    EXTERNAL_PATH: `'${EXTERNAL_PATH}'`,
+    EXTERNAL_PATH: `'${path.join(EXTERNAL_PATH, 'lib/lexer.wasm')}'`,
   } : {
     WASM_BINARY: `'${wasmBuffer.toString('base64')}'`,
     EXTERNAL_PATH: 'undefined'
@@ -36,7 +37,7 @@ if (EXTERNAL_PATH) {
 let lazy;
 async function init () {
   if (!lazy) {
-    lazy = await import(require('node:url').pathToFileURL(require('node:module').createRequire('${EXTERNAL_PATH}/dist/lexer.js').resolve('./lexer.mjs')));
+    lazy = await import(require('node:url').pathToFileURL(require('node:module').createRequire('${path.join(EXTERNAL_PATH, 'dist/lexer.js')}').resolve('./lexer.mjs')));
   }
   module.exports = lazy;
   return lazy.init();

src/lexer.js

@@ -91,11 +91,7 @@ function copyLE (src, outBuf16) {
 }
 
 const loadWasm = (typeof EXTERNAL_PATH === "string" && (async () => {
-  const { readFile } = await import('node:fs/promises');
-  const { fileURLToPath } = await import('node:url');
-  return readFile(fileURLToPath(
-    import.meta.resolve("undefined/dist/lexer.wasm")
-  ));
+  return (await import('node:fs/promises')).readFile(EXTERNAL_PATH);
 })) || (async () => {
   const binary = WASM_BINARY
   if (typeof window !== "undefined" && typeof atob === "function") {