fix: resolve parent xo config from nested cwd

Author: sjh9714

lib/resolve-config.ts

@@ -24,9 +24,8 @@ export async function resolveXoConfig(options: LinterOptions): Promise<{
 			options.cwd = path.resolve(process.cwd(), options.cwd);
 		}
 
-		const stopDirectory = path.dirname(options.cwd);
-
 		const flatConfigExplorer = cosmiconfig(moduleName, {
+			searchStrategy: 'project',
 			searchPlaces: [
 				'package.json',
 				`${moduleName}.config.js`,
@@ -38,7 +37,6 @@ export async function resolveXoConfig(options: LinterOptions): Promise<{
 				'.ts': loadTypeScriptConfig, // eslint-disable-line @typescript-eslint/naming-convention
 				'.mts': loadTypeScriptConfig, // eslint-disable-line @typescript-eslint/naming-convention
 			},
-			stopDir: stopDirectory,
 			cache: true,
 		});
 

test/resolve-config.test.ts

@@ -110,6 +110,36 @@ test('resolves package.json object config', async t => {
 	t.deepEqual(flatOptions, [{space: true}]);
 });
 
+test('resolves parent package.json config from nested package cwd', async t => {
+	const pkg = JSON.parse(await fs.readFile(
+		path.join(t.context.cwd, 'package.json'),
+		'utf8',
+	)) as PackageJson;
+
+	pkg['xo'] = {space: true};
+
+	await fs.writeFile(
+		path.join(t.context.cwd, 'package.json'),
+		JSON.stringify(pkg),
+		'utf8',
+	);
+
+	const packageCwd = path.join(t.context.cwd, 'packages', 'app');
+	await fs.mkdir(packageCwd, {recursive: true});
+	await fs.writeFile(
+		path.join(packageCwd, 'package.json'),
+		JSON.stringify({name: 'app'}),
+		'utf8',
+	);
+
+	const {flatOptions, flatConfigPath} = await resolveXoConfig({
+		cwd: packageCwd,
+	});
+
+	t.deepEqual(flatConfigPath, path.join(t.context.cwd, 'package.json'));
+	t.deepEqual(flatOptions, [{space: true}]);
+});
+
 test('resolves all config extensions types', async t => {
 	const testConfigEsm = `export default [
 		{