add prepack script

Author: lobsterkatie

packages/utils/scripts/prepack.ts

@@ -0,0 +1,27 @@
+/* eslint-disable no-console */
+
+// DO NOT RUN this script yourself!
+// This is invoked from the main `prepack.ts` script in `sentry-javascript/scripts/prepack.ts`.
+
+import * as fs from 'fs';
+import * as fse from 'fs-extra';
+import * as path from 'path';
+
+export function prepack(buildDir: string): boolean {
+  // copy package-specific assets to build dir
+  const assetPath = path.resolve('jsPolyfills');
+  try {
+    if (!fs.existsSync(assetPath)) {
+      console.error(
+        "\nERROR: Missing 'packages/utils/jsPolyfills' directory. Please run `yarn build` in the `utils` package before running this script again.",
+      );
+      return false;
+    }
+    console.log(`Copying 'jsPolyfills' to ${path.resolve(buildDir, 'jsPolyfills')}.`);
+    fse.copySync(assetPath, path.resolve(buildDir, 'jsPolyfills'));
+  } catch (error) {
+    console.error(`\nERROR: Error while copying 'jsPolyfills' to ${buildDir}:\n${error}`);
+    return false;
+  }
+  return true;
+}

scripts/prepack.ts

@@ -73,7 +73,7 @@ try {
 async function runPackagePrepack(packagePrepackPath: string): Promise<void> {
   const { prepack } = await import(packagePrepackPath);
   if (prepack && typeof prepack === 'function') {
-    const isSuccess = prepack(buildDir);
+    const isSuccess = await prepack(buildDir);
     if (!isSuccess) {
       process.exit(1);
     }