Allow specifying the test files and typings file manually (#74)

Author: Karan Sanjeev

readme.md

@@ -220,6 +220,19 @@ Default: `process.cwd()`
 
 Current working directory of the project to retrieve the diagnostics for.
 
+##### typingsFile
+
+Type: `string`<br>
+Default: The `types` property in `package.json`.
+
+Path to the type definition file you want to test. This can be useful when using a test runner to test specific type definitions per test.
+
+##### testFiles
+
+Type: `string[]`<br>
+Default: Finds files with `.test-d.ts` or `.test-d.tsx` extension.
+
+An array of test files with their path. Uses [globby](https://github.com/sindresorhus/globby) under the hood so that you can fine tune test file discovery.
 
 ## License
 

source/lib/compiler.ts

@@ -1,4 +1,3 @@
-import * as path from 'path';
 import {
 	flattenDiagnosticMessageText,
 	createProgram,
@@ -66,11 +65,9 @@ const ignoreDiagnostic = (diagnostic: TSDiagnostic, expectedErrors: Map<Location
  * @returns List of diagnostics
  */
 export const getDiagnostics = (context: Context): Diagnostic[] => {
-	const fileNames = context.testFiles.map(fileName => path.join(context.cwd, fileName));
-
 	const diagnostics: Diagnostic[] = [];
 
-	const program = createProgram(fileNames, context.config.compilerOptions);
+	const program = createProgram(context.testFiles, context.config.compilerOptions);
 
 	const tsDiagnostics = program
 		.getSemanticDiagnostics()

source/lib/index.ts

@@ -9,11 +9,12 @@ import {Context, Config} from './interfaces';
 
 export interface Options {
 	cwd: string;
+	typingsFile?: string;
+	testFiles?: readonly string[];
 }
 
 const findTypingsFile = async (pkg: any, options: Options) => {
-	const typings = pkg.types || pkg.typings || 'index.d.ts';
-
+	const typings = options.typingsFile || pkg.types || pkg.typings || 'index.d.ts';
 	const typingsExist = await pathExists(path.join(options.cwd, typings));
 
 	if (!typingsExist) {
@@ -23,13 +24,37 @@ const findTypingsFile = async (pkg: any, options: Options) => {
 	return typings;
 };
 
-const findTestFiles = async (typingsFile: string, options: Options & {config: Config}) => {
+const normalizeTypingsFilePath = (typingsFilePath: string, options: Options) => {
+	if (options.typingsFile) {
+		return path.basename(typingsFilePath);
+	}
+
+	return typingsFilePath;
+};
+
+const findCustomTestFiles = async (testFilesPattern: readonly string[], cwd: string) => {
+	const testFiles = await globby(testFilesPattern, {cwd});
+
+	if (testFiles.length === 0) {
+		throw new Error('Could not find any test files. Create one and try again');
+	}
+
+	return testFiles.map(file => path.join(cwd, file));
+};
+
+const findTestFiles = async (typingsFilePath: string, options: Options & {config: Config}) => {
+	if (options.testFiles?.length) {
+		return findCustomTestFiles(options.testFiles, options.cwd);
+	}
+
+	// Return only the filename if the `typingsFile` option is used.
+	const typingsFile = normalizeTypingsFilePath(typingsFilePath, options);
+
 	const testFile = typingsFile.replace(/\.d\.ts$/, '.test-d.ts');
 	const tsxTestFile = typingsFile.replace(/\.d\.ts$/, '.test-d.tsx');
 	const testDir = options.config.directory;
 
 	let testFiles = await globby([testFile, tsxTestFile], {cwd: options.cwd});
-
 	const testDirExists = await pathExists(path.join(options.cwd, testDir));
 
 	if (testFiles.length === 0 && !testDirExists) {
@@ -40,7 +65,7 @@ const findTestFiles = async (typingsFile: string, options: Options & {config: Co
 		testFiles = await globby([`${testDir}/**/*.ts`, `${testDir}/**/*.tsx`], {cwd: options.cwd});
 	}
 
-	return testFiles;
+	return testFiles.map(fileName => path.join(options.cwd, fileName));
 };
 
 /**
@@ -56,7 +81,6 @@ export default async (options: Options = {cwd: process.cwd()}) => {
 	}
 
 	const pkg = pkgResult.packageJson;
-
 	const config = loadConfig(pkg as any, options.cwd);
 
 	// Look for a typings file, otherwise use `index.d.ts` in the root directory. If the file is not found, throw an error.

source/test/fixtures/specify-test-files/index.d.ts

@@ -0,0 +1,6 @@
+declare const one: {
+	(foo: string, bar: string): string;
+	(foo: number, bar: number): number;
+};
+
+export default one;

source/test/fixtures/specify-test-files/index.js

@@ -0,0 +1,3 @@
+module.exports.default = (foo, bar) => {
+	return foo + bar;
+};

source/test/fixtures/specify-test-files/package.json

@@ -0,0 +1,3 @@
+{
+	"name": "foo"
+}

source/test/fixtures/specify-test-files/unknown.test.ts

@@ -0,0 +1,5 @@
+import {expectType} from '../../..';
+import one from '.';
+
+expectType<string>(one('foo', 'bar'));
+expectType<string>(one(1, 2));

source/test/fixtures/typings-custom-dir/index.js

@@ -0,0 +1,3 @@
+module.exports.default = (foo, bar) => {
+	return foo + bar;
+};

source/test/fixtures/typings-custom-dir/index.test-d.ts

@@ -0,0 +1,5 @@
+import {expectType} from '../../..';
+import one from './utils';
+
+expectType<string>(one('foo', 'bar'));
+expectType<string>(one(1, 2));

source/test/fixtures/typings-custom-dir/package.json

@@ -0,0 +1,3 @@
+{
+	"name": "foo"
+}