Fix waitUntilExit() not resolved with sync errors

src/ink.tsx

@@ -27,7 +27,7 @@ export type Options = {
 	debug: boolean;
 	exitOnCtrlC: boolean;
 	patchConsole: boolean;
-	waitUntilExit?: () => Promise<void>;
+	initWaitUntilExit: boolean;
 };
 
 export default class Ink {
@@ -116,6 +116,13 @@ export default class Ink {
 				options.stdout.off('resize', this.resized);
 			};
 		}
+
+		if (options.initWaitUntilExit) {
+			this.exitPromise = new Promise((resolve, reject) => {
+				this.resolveExitPromise = resolve;
+				this.rejectExitPromise = reject;
+			});
+		}
 	}
 
 	resized = () => {

src/render.ts

@@ -41,6 +41,13 @@ export type RenderOptions = {
 	 * @default true
 	 */
 	patchConsole?: boolean;
+
+	/**
+	 * Automatically initialize `waitUntilExit` method in order to catch synchronous errors.
+	 *
+	 * @default false
+	 */
+	initWaitUntilExit?: boolean;
 };
 
 export type Instance = {
@@ -80,6 +87,7 @@ const render: RenderFunction = (node, options): Instance => {
 		debug: false,
 		exitOnCtrlC: true,
 		patchConsole: true,
+		initWaitUntilExit: false,
 		...getOptions(options)
 	};
 

test/exit.tsx

@@ -57,6 +57,14 @@ test.serial('exit with thrown error', async t => {
 	t.true(output.includes('errored'));
 });
 
+test.serial(
+	'exit with thrown error when initWaitUntilExit is true',
+	async t => {
+		const output = await run('exit-with-thrown-error-fix');
+		t.true(output.includes('waitUntilExit catch: errored'));
+	}
+);
+
 test.serial('don’t exit while raw mode is active', async t => {
 	await new Promise<void>((resolve, _reject) => {
 		const env: Record<string, string> = {

test/fixtures/exit-with-thrown-error-fix.tsx

@@ -0,0 +1,14 @@
+import React from 'react';
+import {render} from '../../src/index.js';
+
+const Test = () => {
+	throw new Error('errored');
+};
+
+const app = render(<Test />, {initWaitUntilExit: true});
+
+try {
+	await app.waitUntilExit();
+} catch (error: unknown) {
+	console.log(`waitUntilExit catch: ${(error as Error).message}`);
+}