fix(esbuild): transpile with esnext in dev

packages/plugin-vue/src/main.ts

@@ -221,7 +221,11 @@ export async function transformMain(
     const { code, map } = await transformWithEsbuild(
       resolvedCode,
       filename,
-      { loader: 'ts', sourcemap: options.sourceMap },
+      {
+        loader: 'ts',
+        target: 'esnext',
+        sourcemap: options.sourceMap
+      },
       resolvedMap
     )
     resolvedCode = code

packages/vite/package.json

@@ -58,7 +58,7 @@
   },
   "//": "READ CONTRIBUTING.md to understand what to put under deps vs. devDeps!",
   "dependencies": {
-    "esbuild": "^0.15.6",
+    "esbuild": "^0.15.9",
     "postcss": "^8.4.16",
     "resolve": "^1.22.1",
     "rollup": "~2.78.0"

packages/vite/src/node/plugins/esbuild.ts

@@ -179,6 +179,7 @@ export function esbuildPlugin(options: ESBuildOptions = {}): Plugin {
   // Remove optimization options for dev as we only need to transpile them,
   // and for build as the final optimization is in `buildEsbuildPlugin`
   const transformOptions: TransformOptions = {
+    target: 'esnext',
     ...options,
     minify: false,
     minifyIdentifiers: false,

playground/vue/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "compilerOptions": {
+    // esbuild transpile should ignore this
+    "target": "ES5"
+  },
+  "include": ["src"]
+}