[Project Solar / Phase 1 / Cherry-pick] Updated prepublishOnly in package.json to use a custom script (#3563)

Author: didoo

packages/components/package.json

@@ -30,7 +30,8 @@
     "lint:js:fix": "eslint . --fix",
     "lint:types": "glint",
     "start": "rollup --config --watch --environment development",
-    "prepublishOnly": "pnpm build && test -f 'dist/styles/@hashicorp/design-system-components.css' || (echo \"\n\\033[31m⚠️  Error: the pre-compiled CSS file \\`dist/styles/@hashicorp/design-system-components.css\\` was not found\\033[0m\\n\" && exit 1)"
+    "test:dist-files": "node scripts/check-dist-files.mjs",
+    "prepublishOnly": "pnpm build && pnpm test:dist-files"
   },
   "dependencies": {
     "@codemirror/autocomplete": "^6.20.0",

packages/components/scripts/check-dist-files.mjs

@@ -0,0 +1,23 @@
+#!/usr/bin/env node
+
+import { existsSync } from 'node:fs';
+
+const FILES_TO_CHECK = [
+  'dist/styles/@hashicorp/design-system-components.css',
+  'dist/styles/@hashicorp/design-system-power-select-overrides.css',
+];
+
+let hasErrors = false;
+
+for (const file of FILES_TO_CHECK) {
+  if (!existsSync(file)) {
+    console.error(
+      `\n\x1b[31m⚠️  Error: the pre-compiled CSS file \`${file}\` was not found\x1b[0m\n`
+    );
+    hasErrors = true;
+  }
+}
+
+if (hasErrors) {
+  process.exit(1);
+}