fix: use resolve instead of join (vuejs#33)

Allows the documentation to exist in a folder e.g. `docs`, and running `vitepress dev
docs` as well as `vitepress build docs`

bin/vitepress.js

@@ -6,13 +6,13 @@ console.log(chalk.cyan(`vitepress v${require('../package.json').version}`))
 console.log(chalk.cyan(`vite v${require('vite/package.json').version}`))
 
 const command = argv._[0]
+const root = argv._[command ? 1 : 0]
+if (root) {
+  argv.root = root
+}
 
 if (!command || command === 'dev') {
   const port = argv.port || 3000
-  const root = command === 'dev' && argv._[1]
-  if (root) {
-    argv.root = root
-  }
   require('../dist/node')
     .createServer(argv)
     .then((server) => {

src/node/build/render.ts

@@ -84,7 +84,7 @@ function resolvePageImports(
   // find the page's js chunk and inject script tags for its imports so that
   // they are start fetching as early as possible
 
-  const srcPath = path.join(config.root, page)
+  const srcPath = path.resolve(config.root, page)
   const pageChunk = result.assets.find(
     (chunk) => chunk.type === 'chunk' && chunk.facadeModuleId === srcPath
   ) as OutputChunk