From 309e5e32bd847751439ae1467842af55bf4e8a6f Mon Sep 17 00:00:00 2001
From: Mark de Bruijn <mark.de.bruijn@infi.nl>
Date: Fri, 15 May 2020 12:41:26 +0200
Subject: [PATCH] Force esbuild to output ES2019

Rollup does not appear to support optional chaining (`foo?.bar`). Work
around this by lowering the esbuild target to ES2019

Related: https://github.com/rollup/plugins/issues/205
---
 src/node/esbuildService.ts | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/node/esbuildService.ts b/src/node/esbuildService.ts
index f62f8ba029b4c8..6c4995107551b9 100644
--- a/src/node/esbuildService.ts
+++ b/src/node/esbuildService.ts
@@ -62,7 +62,8 @@ export const transform = async (
     ...options,
     loader: options.loader || (path.extname(file).slice(1) as any),
     sourcemap: true,
-    sourcefile: file
+    sourcefile: file,
+    target: 'es2019'
   }
   try {
     const result = await service.transform(src, options)