fix: generate sitemap from an absolute path

eg. `sitemap: { path: /sitemap.xml }`

README.md

@@ -66,7 +66,7 @@ The `routes` parameter follows the same way than the `generate` [configuration](
 See as well the [routes](#routes-1) examples below.
 
 ### `path` (optional)
-- Default: `sitemap.xml`
+- Default: `/sitemap.xml`
 
 The URL path of the generated sitemap.
 

lib/module.js

@@ -13,7 +13,7 @@ const defaultPublicPath = '/_nuxt/'
 
 module.exports = function module (moduleOptions) {
   const defaults = {
-    path: 'sitemap.xml',
+    path: '/sitemap.xml',
     hostname: this.options.build.publicPath !== defaultPublicPath ? this.options.build.publicPath : undefined,
     exclude: [],
     routes: this.options.generate.routes || [],
@@ -77,13 +77,13 @@ module.exports = function module (moduleOptions) {
     const routes = await cache.get('routes')
     const sitemap = await createSitemap(options, routes)
     const xml = await sitemap.toXML()
-    const xmlGeneratePath = path.resolve(this.options.generate.dir, options.path)
+    const xmlGeneratePath = path.join(this.options.generate.dir, options.path)
     await fs.ensureFile(xmlGeneratePath)
     await fs.writeFile(xmlGeneratePath, xml)
     consola.success('Generated', xmlGeneratePath.replace(this.options.generate.dir, ''))
     if (options.gzip) {
       const gzip = await sitemap.toGzip()
-      const gzipGeneratePath = path.resolve(this.options.generate.dir, options.pathGzip)
+      const gzipGeneratePath = path.join(this.options.generate.dir, options.pathGzip)
       await fs.ensureFile(gzipGeneratePath)
       await fs.writeFile(gzipGeneratePath, gzip)
       consola.success('Generated', gzipGeneratePath.replace(this.options.generate.dir, ''))

test/fixture/nuxt.config.js

@@ -9,6 +9,7 @@ module.exports = {
   },
   modules: ['@@'],
   sitemap: {
+    path: '/sitemap.xml',
     exclude: [
       '/exclude'
     ],