build: add files of vant-cli 2

packages/vant-cli/src/commands/dev.ts

@@ -0,0 +1,39 @@
+import webpack from 'webpack';
+import WebpackDevServer from 'webpack-dev-server';
+import webpackDevConfig from '../config/webpack.site.dev';
+import { getPort } from 'portfinder';
+import { clean } from '../commands/clean';
+import { genMobileConfig } from '../compiler/gen-mobile-config';
+import { genDesktopConfig } from '../compiler/gen-desktop-config';
+
+function runWebpack() {
+  const server = new WebpackDevServer(
+    webpack(webpackDevConfig),
+    (webpackDevConfig as any).devServer
+  );
+
+  getPort(
+    {
+      port: 8080
+    },
+    (err, port) => {
+      if (err) {
+        console.log(err);
+        return;
+      }
+
+      server.listen(port, 'localhost', (err?: Error) => {
+        if (err) {
+          console.log(err);
+        }
+      });
+    }
+  );
+}
+
+export function dev() {
+  clean();
+  genMobileConfig();
+  genDesktopConfig();
+  runWebpack();
+}