fix sourcemap uploading issue due to filename

rollup.config.js

@@ -1,13 +1,17 @@
 "use strict";
 
+import fs from "fs";
+import path from "path";
 import resolve from "rollup-plugin-node-resolve";
 import commonjs from "rollup-plugin-commonjs";
 import screepsUpload from "rollup-plugin-screeps-upload";
 import typescript from "rollup-plugin-typescript2";
 
+const getSourcemapFilename = () => 'main.js.map.js'
+
 // In Screeps, require only works for exported content
 // This "plugin" prepends an export to source maps so that it can be loaded in screeps via require`
-function exportSourceMaps() {
+function exportSourceMaps(options) {
   return {
     name: "export-source-maps",
     ongenerate: function (options, bundle) {
@@ -18,6 +22,12 @@ function exportSourceMaps() {
       bundle.map.toString = function () {
         return "module.exports = " + tmp.apply(this, arguments) + ";";
       }
+    },
+    onwrite: function ({ bundle }) {
+      const map = bundle.map
+      fs.writeFileSync(path.resolve(__dirname, `./dist/${options || getSourcemapFilename()}`), map);
+      // Delete the old file
+      fs.unlinkSync(path.resolve(__dirname, `./dist/main.js.map`));
     }
   }
 }
@@ -35,7 +45,7 @@ export default {
     resolve(),
     commonjs(),
     typescript({tsconfig: "./tsconfig.json"}),
-    exportSourceMaps(),
-    screepsUpload('./screeps.json')
+    exportSourceMaps("main.js.map.js"),
+    screepsUpload("./screeps.json")
   ]
 }