From 6559f687821324dfa3a88c0445ea14ee059f72c7 Mon Sep 17 00:00:00 2001
From: Lukas Taegert-Atkinson <lukastaegert@users.noreply.github.com>
Date: Sat, 10 Apr 2021 07:02:13 +0200
Subject: [PATCH] Do not fail when returning null or undefined from an async
 options hook (#4039)

---
 src/rollup/rollup.ts                          |  7 +++---
 test/function/samples/aync-options/_config.js | 25 +++++++++++++++++++
 test/function/samples/aync-options/main.js    |  1 +
 3 files changed, 30 insertions(+), 3 deletions(-)
 create mode 100644 test/function/samples/aync-options/_config.js
 create mode 100644 test/function/samples/aync-options/main.js

diff --git a/src/rollup/rollup.ts b/src/rollup/rollup.ts
index c3dffad1299..86519eb5439 100644
--- a/src/rollup/rollup.ts
+++ b/src/rollup/rollup.ts
@@ -122,13 +122,14 @@ function applyOptionHook(watchMode: boolean) {
 		inputOptions: Promise<GenericConfigObject>,
 		plugin: Plugin
 	): Promise<GenericConfigObject> => {
-		if (plugin.options)
+		if (plugin.options) {
 			return (
-				(plugin.options.call(
+				((await plugin.options.call(
 					{ meta: { rollupVersion, watchMode } },
 					await inputOptions
-				) as GenericConfigObject) || inputOptions
+				)) as GenericConfigObject) || inputOptions
 			);
+		}
 
 		return inputOptions;
 	};
diff --git a/test/function/samples/aync-options/_config.js b/test/function/samples/aync-options/_config.js
new file mode 100644
index 00000000000..31fa811ee27
--- /dev/null
+++ b/test/function/samples/aync-options/_config.js
@@ -0,0 +1,25 @@
+const assert = require('assert');
+
+module.exports = {
+	description: 'handles async plugin options',
+	options: {
+		preserveEntrySignatures: false,
+		plugins: [
+			{
+				options(options) {
+					assert.strictEqual(options.preserveEntrySignatures, false);
+					return Promise.resolve({ ...options, preserveEntrySignatures: 'strict' });
+				}
+			},
+			{
+				options(options) {
+					assert.strictEqual(options.preserveEntrySignatures, 'strict');
+					return Promise.resolve(null);
+				}
+			}
+		]
+	},
+	exports(exports) {
+		assert.strictEqual(exports.foo, 1);
+	}
+};
diff --git a/test/function/samples/aync-options/main.js b/test/function/samples/aync-options/main.js
new file mode 100644
index 00000000000..bb1843d113a
--- /dev/null
+++ b/test/function/samples/aync-options/main.js
@@ -0,0 +1 @@
+export const foo = 1;