Convert WPT test harness to TS

build/wpt_test.bzl

@@ -53,7 +53,7 @@ const unitTests :Workerd.Config = (
       worker = (
         modules = [
           (name = "worker", esModule = embed "{test_js}"),
-          (name = "harness", esModule = embed "../../../../../workerd/src/wpt/harness.js"),
+          (name = "wpt:harness", esModule = embed "../../../../../workerd/src/wpt/harness.js"),
           {modules}
         ],
         bindings = [

src/workerd/api/wpt/url-test.js

@@ -2,7 +2,7 @@
 // Licensed under the Apache 2.0 license found in the LICENSE file or at:
 //     https://opensource.org/licenses/Apache-2.0
 
-import { run } from 'harness';
+import { run } from 'wpt:harness';
 
 export const idnaTestV2Window = run('IdnaTestV2.window.js');
 export const historical = run('historical.any.js', {

src/workerd/api/wpt/urlpattern-test.js

@@ -2,7 +2,7 @@
 // Licensed under the Apache 2.0 license found in the LICENSE file or at:
 //     https://opensource.org/licenses/Apache-2.0
 
-import { run } from 'harness';
+import { run } from 'wpt:harness';
 
 export const urlpatternCompareTests = run(
   'urlpattern-compare-tests.tentative.js',

src/wpt/BUILD.bazel

@@ -1,8 +1,18 @@
-filegroup(
+load("@aspect_rules_ts//ts:defs.bzl", "ts_project")
+
+ts_project(
     name = "wpt-test-harness",
+    testonly = False,
     srcs = glob(
-        include = ["**/*"],
-        allow_empty = True,
+        [
+            "*.ts",
+        ],
     ),
+    allow_js = True,
+    declaration = True,
+    tsconfig = "tsconfig.json",
     visibility = ["//visibility:public"],
+    deps = [
+        "//:node_modules/@types",
+    ],
 )

src/wpt/eslint.config.mjs

@@ -0,0 +1,3 @@
+import { baseConfig } from '../../tools/base.eslint.config.mjs';
+
+export default [...baseConfig({ tsconfigRootDir: import.meta.dirname })];

src/wpt/harness.js → src/wpt/harness.ts

@@ -32,12 +32,68 @@ import {
   throws,
 } from 'node:assert';
 
-function OptionalFeatureUnsupportedError(message) {
-  AssertionError.call(this, message);
+type Options = {
+  expectedFailures?: string[];
+  verbose?: boolean;
+  skippedTests?: string[];
+};
+
+type TestRunnerFn = (callback: TestFn | PromiseTestFn, message: string) => void;
+type TestFn = () => void;
+type PromiseTestFn = () => Promise<void>;
+type ThrowingFn = () => any;
+
+declare namespace globalThis {
+  var errors: Error[];
+  var testOptions: Options;
+  var Window: typeof globalThis;
+  var self: typeof globalThis;
+  var GLOBAL: { isWindow(): boolean };
+  function fetch(url: string): Promise<{ json(): Promise<any> }>;
+  function test(func: TestFn, name: string): void;
+  function done(): undefined;
+  function subsetTestByKey(
+    _key: any,
+    testType: TestRunnerFn,
+    testCallback: TestFn | PromiseTestFn,
+    testMessage: string
+  ): void;
+  function promise_test(
+    func: PromiseTestFn,
+    name: string,
+    properties?: any
+  ): void;
+  function assert_equals(a: any, b: any, message?: string): void;
+  function assert_not_equals(a: any, b: any, message?: string): void;
+  function assert_true(val: any, message?: string): void;
+  function assert_false(val: any, message?: string): void;
+  function assert_array_equals(a: any, b: any, message?: string): void;
+  function assert_object_equals(a: any, b: any, message?: string): void;
+  function assert_implements(condition: any, description?: string): void;
+  function assert_implements_optional(
+    condition: any,
+    description?: string
+  ): void;
+  function assert_unreached(description?: string): void;
+  function assert_throws_js(
+    constructor: any,
+    func: ThrowingFn,
+    description?: string
+  ): void;
+  function assert_throws_exactly(
+    exception: any,
+    fn: ThrowingFn,
+    description?: string
+  ): void;
+  function assert_throws_dom(
+    type: any,
+    funcOrConstructor: any,
+    descriptionOrFunc: any,
+    maybeDescription: any
+  ): void;
 }
-OptionalFeatureUnsupportedError.prototype = Object.create(
-  AssertionError.prototype
-);
+
+class OptionalFeatureUnsupportedError extends AssertionError {}
 
 globalThis.Window = Object.getPrototypeOf(globalThis).constructor;
 
@@ -67,13 +123,7 @@ globalThis.subsetTestByKey = (_key, testType, testCallback, testMessage) => {
   return testType(testCallback, testMessage);
 };
 
-globalThis.promise_test = async (func, name, properties) => {
-  if (typeof func !== 'function') {
-    properties = name;
-    name = func;
-    func = null;
-  }
-
+globalThis.promise_test = async (func, name, _properties) => {
   if (!shouldRunTest(name)) {
     return;
   }
@@ -140,7 +190,7 @@ globalThis.assert_implements = (condition, description) => {
  */
 globalThis.assert_implements_optional = (condition, description) => {
   if (!condition) {
-    throw new OptionalFeatureUnsupportedError(description);
+    throw new OptionalFeatureUnsupportedError({ message: description });
   }
 };
 
@@ -219,7 +269,7 @@ globalThis.assert_throws_exactly = (exception, fn, description) => {
  *
  */
 globalThis.assert_throws_dom = (
-  type,
+  _type,
   funcOrConstructor,
   descriptionOrFunc,
   maybeDescription
@@ -230,6 +280,7 @@ globalThis.assert_throws_dom = (
     func = descriptionOrFunc;
     description = maybeDescription;
   } else {
+    // @ts-ignore
     constructor = this.DOMException;
     func = funcOrConstructor;
     description = descriptionOrFunc;
@@ -251,7 +302,7 @@ globalThis.assert_throws_dom = (
 /**
  * Create a synchronous test
  *
- * @param {TestFunction} func - Test function. This is executed
+ * @param {TestFn} func - Test function. This is executed
  * immediately. If it returns without error, the test status is
  * set to ``PASS``. If it throws an :js:class:`AssertionError`, or
  * any other exception, the test status is set to ``FAIL``
@@ -273,7 +324,7 @@ globalThis.test = (func, name) => {
 
 globalThis.errors = [];
 
-function shouldRunTest(message) {
+function shouldRunTest(message: string) {
   if ((globalThis.testOptions.skippedTests ?? []).includes(message)) {
     return false;
   }
@@ -285,12 +336,12 @@ function shouldRunTest(message) {
   return true;
 }
 
-function prepare(options) {
+function prepare(options: Options) {
   globalThis.errors = [];
   globalThis.testOptions = options;
 }
 
-function sanitizeMessage(message) {
+function sanitizeMessage(message: string) {
   // Test logs will be exported to XML, so we must escape any characters that
   // are forbidden in an XML CDATA section, namely "[...] the surrogate blocks,
   // FFFE, and FFFF".
@@ -308,7 +359,7 @@ function sanitizeMessage(message) {
   );
 }
 
-function validate(testFileName, options) {
+function validate(testFileName: string, options: Options) {
   const expectedFailures = new Set(options.expectedFailures ?? []);
 
   let failing = false;
@@ -332,7 +383,7 @@ function validate(testFileName, options) {
   }
 }
 
-export function run(file, options = {}) {
+export function run(file: string, options: Options = {}) {
   return {
     async test() {
       prepare(options);

src/wpt/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "ESNext",
+    "lib": ["ESNext", "dom"],
+    "alwaysStrict": true,
+    "strict": true,
+    "allowJs": true,
+    "allowUnreachableCode": false,
+    "allowUnusedLabels": false,
+    "exactOptionalPropertyTypes": true,
+    "noFallthroughCasesInSwitch": true,
+    "noImplicitOverride": true,
+    "noImplicitReturns": true,
+    "noPropertyAccessFromIndexSignature": false,
+    "noUncheckedIndexedAccess": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "strictNullChecks": true,
+    "esModuleInterop": true,
+    "moduleResolution": "node",
+    "declaration": true,
+    "paths": {
+      "wpt:*": ["./*"]
+    }
+  },
+  "exclude": []
+}