Fix processing of config files containing the rootDir option

source/lib/config.ts

@@ -1,4 +1,3 @@
-import * as path from 'path';
 import {
 	JsxEmit,
 	ScriptTarget,
@@ -56,7 +55,7 @@ function getOptionsFromTsConfig(cwd: string): CompilerOptions {
 	return parseJsonSourceFileConfigFileContent(
 		readJsonConfigFile(configPath, sys.readFile),
 		sys,
-		path.basename(configPath),
+		cwd,
 		undefined,
 		configPath,
 	).options;

source/test/fixtures/root-dir/package.json

@@ -0,0 +1,4 @@
+{
+	"name": "test",
+	"types": "ts-dist/index.d.ts"
+}

source/test/fixtures/root-dir/src/index.ts

@@ -0,0 +1 @@
+export const a = 2;

source/test/fixtures/root-dir/test-d/index.test-d.ts

@@ -0,0 +1,4 @@
+import {expectType} from '../../../..';
+import {a} from '../src';
+
+expectType<2>(a);

source/test/fixtures/root-dir/ts-dist/index.d.ts

@@ -0,0 +1 @@
+export declare const a = 2;

source/test/fixtures/root-dir/ts-dist/index.js

@@ -0,0 +1,4 @@
+'use strict';
+exports.__esModule = true;
+exports.a = void 0;
+exports.a = 2;

source/test/fixtures/root-dir/tsconfig.json

@@ -0,0 +1,12 @@
+{
+	"compilerOptions": {
+		"rootDir": "./src",
+		"outDir": "ts-dist"
+	},
+	"include": [
+		"src"
+	],
+	"exclude": [
+		"**/ts-dist/**"
+	]
+}

source/test/test.ts

@@ -390,3 +390,9 @@ test('errors in libs from node_modules are not reported', async t => {
 		[3, 18, 'error', 'Cannot find name \'Bar\'.']
 	]);
 });
+
+test('allow specifying `rootDir` option in `tsconfig.json`', async t => {
+	const diagnostics = await tsd({cwd: path.join(__dirname, 'fixtures/root-dir')});
+
+	verify(t, diagnostics, []);
+});