Fill out more of the node:util implementation

src/node/internal/debuglog.ts

@@ -0,0 +1,77 @@
+// Copyright (c) 2017-2023 Cloudflare, Inc.
+// Licensed under the Apache 2.0 license found in the LICENSE file or at:
+//     https://opensource.org/licenses/Apache-2.0
+//
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+/* todo: the following is adopted code, enabling linting one day */
+/* eslint-disable */
+
+import {
+  format,
+  formatWithOptions,
+} from 'node-internal:internal_inspect';
+
+let debugImpls : object = {};
+
+function debuglogImpl(set: string) {
+  if ((debugImpls as any)[set] === undefined) {
+    (debugImpls as any)[set] = function debug(...args : any[]) {
+      const msg = formatWithOptions({ }, ...args);
+      console.log(format('%s: %s\n', set, msg));
+    };
+  }
+  return (debugImpls as any)[set];
+}
+
+// In Node.js' implementation, debuglog availability is determined by the NODE_DEBUG
+// environment variable. However, we don't have access to the environment variables
+// in the same way. Instead, we'll just always enable debuglog on the requested sets.
+export function debuglog(set : string, cb? : (debug : (...args : any[]) => void) => void) {
+  function init() {
+    set = set.toUpperCase();
+  }
+  let debug = (...args : any[]) => {
+    init();
+    debug = debuglogImpl(set);
+    if (typeof cb === 'function') {
+      cb(debug);
+    }
+    switch (args.length) {
+      case 1: return debug(args[0]);
+      case 2: return debug(args[0], args[1]);
+      default: return debug(...args);
+    }
+  };
+  const logger = (...args : any[]) => {
+    switch (args.length) {
+      case 1: return debug(args[0]);
+      case 2: return debug(args[0], args[1]);
+      default: return debug(...args);
+    }
+  };
+  Object.defineProperty(logger, 'enabled', {
+    get() { return true; },
+    configurable: true,
+    enumerable: true,
+  });
+  return logger;
+}

src/node/util.ts

@@ -9,9 +9,17 @@ import { default as internalTypes } from 'node-internal:internal_types';
 import { default as utilImpl } from 'node-internal:util';
 
 import {
-  validateFunction
+  validateFunction,
+  validateAbortSignal,
+  validateObject,
 } from 'node-internal:validators';
 
+import {
+  debuglog,
+} from 'node-internal:debuglog';
+export const debug = debuglog;
+export { debuglog };
+
 import {
   ERR_FALSY_VALUE_REJECTION,
   ERR_INVALID_ARG_TYPE,
@@ -171,6 +179,74 @@ export function _extend(target: Object, source: Object) {
   return target;
 }
 
+export const TextDecoder = globalThis.TextDecoder;
+export const TextEncoder = globalThis.TextEncoder;
+
+export function toUSVString(input : any) {
+  // TODO(cleanup): Apparently the typescript types for this aren't available yet?
+  return (`${input}` as any).toWellFormed();
+}
+
+function pad(n: any) : string {
+  return `${n}`.padStart(2, '0');
+}
+
+const months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep',
+                'Oct', 'Nov', 'Dec'];
+
+function timestamp() : string {
+  const d = new Date();
+  const t = [
+    pad(d.getHours()),
+    pad(d.getMinutes()),
+    pad(d.getSeconds()),
+  ].join(':');
+  return `${d.getDate()} ${months[d.getMonth()]} ${t}`;
+}
+
+export function log(...args : any[]) {
+  console.log('%s - %s', timestamp(), format(...args));
+}
+
+export function parseArgs(..._ : any[]) : any {
+  // We currently have no plans to implement the util.parseArgs API.
+  throw new Error('node:util parseArgs is not implemented');
+}
+
+export function transferableAbortController(..._ : any[]) : any {
+  throw new Error('node:util transferableAbortController is not implemented');
+}
+
+export function transferableAbortSignal(..._ : any[]) : any {
+  throw new Error('node:util transferableAbortSignal is not implemented');
+}
+
+export async function aborted(signal: AbortSignal, resource: object) {
+  if (signal === undefined) {
+    throw new ERR_INVALID_ARG_TYPE('signal', 'AbortSignal', signal);
+  }
+  // Node.js defines that the resource is held weakly such that if it is gc'd, we
+  // will drop the event handler on the signal and the promise will remain pending
+  // forever. We don't want gc to be observable in the same way so we won't support
+  // this additional option. Unfortunately Node.js does not make this argument optional.
+  // We'll just ignore it.
+  validateAbortSignal(signal, 'signal');
+  validateObject(resource, 'resource', { allowArray: true, allowFunction: true });
+  if (signal.aborted) return Promise.resolve();
+  // TODO(cleanup): Apparently withResolvers isn't part of type defs we use yet
+  const { promise, resolve } = (Promise as any).withResolvers();
+  const opts = { __proto__: null, once: true };
+  signal.addEventListener('abort', resolve, opts);
+  return promise;
+}
+
+export function deprecate(fn: Function, _1?: string, _2?: string, _3? : boolean) {
+  // TODO(soon): Node.js's implementation wraps the given function in a new function that
+  // logs a warning to the console if the function is called. Do we want to support that?
+  // For now, we're just going to silently return the input method unmodified.
+  return fn;
+}
+
 export default {
   types,
   callbackify,
@@ -183,18 +259,42 @@ export default {
   _extend,
   MIMEParams,
   MIMEType,
+  toUSVString,
+  log,
+  aborted,
+  debuglog,
+  debug,
+  deprecate,
+  // Node.js originally exposed TextEncoder and TextDecoder off the util
+  // module originally, so let's just go ahead and do the same.
+  TextEncoder,
+  TextDecoder,
+  // We currently have no plans to implement the following APIs but we want
+  // to provide throwing placeholders for them. We may eventually come back
+  // around and implement these later.
+  parseArgs,
+  transferableAbortController,
+  transferableAbortSignal,
 };
 
 // Node.js util APIs we're currently not supporting
-// TODO(soon): Revisit these
-//
-// debug/debuglog -- The semantics of these depend on configuration through environment
-//                   variables to enable specific debug categories. We have no notion
-//                   of that in the runtime currently and it's not yet clear if we should.
-// deprecate -- Not clear how broadly this is used in the ecosystem outside of node.js
-// getSystemErrorMap/getSystemErrorName -- libuv specific. No use in workerd?
-// is{Type} variants -- these are deprecated in Node. Use util.types
-// toUSVString -- Not clear how broadly this is used in the ecosystem outside of node.js.
-//                also this is soon to be obsoleted by toWellFormed in the language.
-// transferableAbortSignal/transferableAbortController -- postMessage and worker threads
-//      are not implemented in workerd. No use case for these.
+//   * util._errnoException
+//   * util._exceptionWithHostPort
+//   * util.getSystemErrorMap
+//   * util.getSystemErrorName
+//   * util.isArray
+//   * util.isBoolean
+//   * util.isBuffer
+//   * util.isDate
+//   * util.isDeepStrictEqual
+//   * util.isError
+//   * util.isFunction
+//   * util.isNull
+//   * util.isNullOrUndefined
+//   * util.isNumber
+//   * util.isObject
+//   * util.isPrimitive
+//   * util.isRegExp
+//   * util.isString
+//   * util.isSymbol
+//   * util.isUndefined

src/workerd/api/node/util-nodejs-test.js

@@ -24,6 +24,7 @@
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 import assert from 'node:assert';
+import { mock } from 'node:test';
 import util, { inspect } from 'node:util';
 
 const remainingMustCallErrors = new Set();
@@ -3777,3 +3778,49 @@ export const utilInspectError = {
     );
   }
 };
+
+export const logTest = {
+  test() {
+    const original = console.log;
+    console.log = mock.fn();
+
+    util.log('test');
+
+    assert.strictEqual(console.log.mock.callCount(), 1);
+    const args = console.log.mock.calls[0].arguments;
+    assert.strictEqual(args.length, 3);
+    assert.strictEqual(args[0], '%s - %s');
+    // skipping the check on args[1] since it'll be a timestamp that changes
+    assert.strictEqual(args[2], 'test');
+
+    console.log = original;
+  }
+};
+
+export const aborted = {
+  async test() {
+    const signal = AbortSignal.timeout(10);
+    await util.aborted(signal, {});
+
+    await assert.rejects(util.aborted({}, {}), {
+      message: 'The "signal" argument must be an instance of AbortSignal. ' +
+               'Received an instance of Object'
+    });
+  }
+};
+
+export const debuglog = {
+  test() {
+    const original = console.log;
+    console.log = mock.fn();
+
+    util.debuglog('test')('hello');
+
+    assert.strictEqual(console.log.mock.callCount(), 1);
+    const args = console.log.mock.calls[0].arguments;
+    assert.strictEqual(args.length, 1);
+    assert.strictEqual(args[0], 'TEST: hello\n');
+
+    console.log = original;
+  }
+};