fix(ext/node): Implement isBuiltin in node:module

ext/node/polyfills/01_require.js

@@ -1181,6 +1181,25 @@ function createRequire(filenameOrUrl) {
   return createRequireFromPath(filename);
 }
 
+function isBuiltin(moduleName) {
+  if (typeof moduleName !== "string") {
+    return false;
+  }
+
+  if (StringPrototypeStartsWith(moduleName, "node:")) {
+    moduleName = StringPrototypeSlice(moduleName, 5);
+  } else if (moduleName === "test") {
+    // test is only a builtin if it has the "node:" scheme
+    // see https://github.com/nodejs/node/blob/73025c4dec042e344eeea7912ed39f7b7c4a3991/test/parallel/test-module-isBuiltin.js#L14
+    return false;
+  }
+
+  return moduleName in nativeModuleExports &&
+    !StringPrototypeStartsWith(moduleName, "internal/");
+}
+
+Module.isBuiltin = isBuiltin;
+
 Module.createRequire = createRequire;
 
 Module._initPaths = function () {
@@ -1249,7 +1268,7 @@ internals.requireImpl = {
   nativeModuleExports,
 };
 
-export { builtinModules, createRequire, Module };
+export { builtinModules, createRequire, isBuiltin, Module };
 export const _cache = Module._cache;
 export const _extensions = Module._extensions;
 export const _findPath = Module._findPath;

tests/testdata/npm/compare_globals/main.out

@@ -4,7 +4,7 @@ Download http://localhost:4545/npm/registry/@denotest/globals
 [UNORDERED_END]
 [UNORDERED_START]
 Download http://localhost:4545/npm/registry/@denotest/globals/1.0.0.tgz
-Download http://localhost:4545/npm/registry/@types/node/node-18.8.2.tgz
+Download http://localhost:4545/npm/registry/@types/node/node-18.16.19.tgz
 [UNORDERED_END]
 Check file:///[WILDCARD]/npm/compare_globals/main.ts
 true

tests/testdata/publish/bare_node_builtins.out

@@ -1,7 +1,7 @@
 Warning: Resolving "url" as "node:url" at file:///[WILDCARD]/publish/bare_node_builtins/mod.ts:1:22. If you want to use a built-in Node module, add a "node:" prefix.
 Warning: Resolving "url" as "node:url" at file:///[WILDCARD]/publish/bare_node_builtins/mod.ts:1:22. If you want to use a built-in Node module, add a "node:" prefix.
 Download http://localhost:4545/npm/registry/@types/node
-Download http://localhost:4545/npm/registry/@types/node/node-18.8.2.tgz
+Download http://localhost:4545/npm/registry/@types/node/node-18.16.19.tgz
 Check file:///[WILDCARD]/publish/bare_node_builtins/mod.ts
 Checking for slow types in the public API...
 Check file:///[WILDCARD]/publish/bare_node_builtins/mod.ts

tests/testdata/publish/bare_node_builtins_no_warnings.out

@@ -1,5 +1,5 @@
 Download http://localhost:4545/npm/registry/@types/node
-Download http://localhost:4545/npm/registry/@types/node/node-18.8.2.tgz
+Download http://localhost:4545/npm/registry/@types/node/node-18.16.19.tgz
 Check file:///[WILDCARD]/publish/bare_node_builtins/mod.ts
 Checking for slow types in the public API...
 Check file:///[WILDCARD]/publish/bare_node_builtins/mod.ts

tests/unit_node/module_test.ts

@@ -1,6 +1,6 @@
 // Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
 
-import { createRequire, Module } from "node:module";
+import { createRequire, isBuiltin, Module } from "node:module";
 import { assert, assertEquals } from "@std/assert/mod.ts";
 import process from "node:process";
 import * as path from "node:path";
@@ -70,3 +70,16 @@ Deno.test("Built-in Node modules have `node:` prefix", () => {
 
   assert(thrown);
 });
+
+Deno.test("[node/module isBuiltin] recognizes node builtins", () => {
+  assert(isBuiltin("node:fs"));
+  assert(isBuiltin("node:test"));
+  assert(isBuiltin("fs"));
+  assert(isBuiltin("buffer"));
+
+  assert(!isBuiltin("internal/errors"));
+  assert(!isBuiltin("test"));
+  assert(!isBuiltin(""));
+  // deno-lint-ignore no-explicit-any
+  assert(!isBuiltin(undefined as any));
+});