generate files if not existent

packages/nuxt/build.config.ts

@@ -1,6 +1,4 @@
 import { defineBuildConfig } from 'unbuild';
 
 // Build Config for the Nuxt Module Builder: https://github.com/nuxt/module-builder
-export default defineBuildConfig({
-  failOnWarn: false,
-});
+export default defineBuildConfig({});

packages/nuxt/generate-build-stubs.bash

@@ -0,0 +1,19 @@
+# The Nuxt package is built in 2 steps and the nuxt-module-builder shows a warning if one of the files specified in the package.json is missing.
+# unbuild checks for this: https://github.com/unjs/unbuild/blob/8c647ec005a02f852e56aeef6076a35eede17df1/src/validate.ts#L81
+
+# The runtime folder (which is built with the nuxt-module-builder) is separate from the rest of the package and therefore we can ignore those warnings
+# as those files are generated in the other build step.
+
+# Create the directories if they do not exist
+mkdir -p build/cjs
+mkdir -p build/esm
+mkdir -p build/types
+
+# Write files if they do not exist
+[ ! -f build/cjs/index.server.js ] && echo "module.exports = {}" > build/cjs/index.server.js
+[ ! -f build/cjs/index.client.js ] && echo "module.exports = {}" > build/cjs/index.client.js
+[ ! -f build/esm/index.server.js ] && echo "export {}" > build/esm/index.server.js
+[ ! -f build/esm/index.client.js ] && echo "export {}" > build/esm/index.client.js
+[ ! -f build/types/index.types.d.ts ] && echo "export {}" > build/types/index.types.d.ts
+
+echo "Created build stubs for missing files"

packages/nuxt/package.json

@@ -58,7 +58,7 @@
   "scripts": {
     "build": "run-s build:types build:transpile",
     "build:dev": "yarn build",
-    "build:nuxt-module": "nuxt-module-build build --outDir build/module",
+    "build:nuxt-module": "bash ./generate-build-stubs.bash && nuxt-module-build build --outDir build/module",
     "build:transpile": "rollup -c rollup.npm.config.mjs && yarn build:nuxt-module",
     "build:types": "tsc -p tsconfig.types.json",
     "build:watch": "run-p build:transpile:watch build:types:watch",