implement domainToASCII and domainToUnicode

[anonrig]

Implements domainToASCII and domainToUnicode and exports them under node:url where URL and URLSearchParams also exist.

[jasnell]

@IgorMinar ... please take a look

[IgorMinar]

LGTM

For those wondering how this PR relates to unjs/unenv#299, @anonrig clarified with me that these two methods are nearly impossible to implement in userland in a performant way. So we are implementing them natively, while other parts of node:url could come in via unenv.

// fyi: @pi0

[jasnell]

@pi0 ... so you know what to expect... these will be exported by the runtime as the node:url module. The bundler will essentially need to alias node:url, use the process.getBuiltinModule('node:url') API to get the built-in version to extend (that has these methods), then re-export the fully patched module.

[IgorMinar]

@pi0 ... so you know what to expect... these will be exported by the runtime as the node:url module. The bundler will essentially need to alias node:url, use the process.getBuiltinModule('node:url') API to get the built-in version to extend (that has these methods), then re-export the fully patched module.

Yes! except unenv will do exactly this in a new file we'll create under https://github.com/unjs/unenv/tree/main/src/runtime/node/url called $cloudflare.ts, following the existing precedence for hybrid modules: https://github.com/unjs/unenv/blob/main/src/runtime/node/buffer/%24cloudflare.ts

Bundlers then pick up url/$cloudflare.ts as instructed by the cloudflare preset (which also needs to be updated to include url) and combine it all into the final bundle.

[jasnell]

@anonrig ... as discussed in chat, let's make sure this is added to the test:

diff --git a/src/workerd/api/node/tests/url-nodejs-test.js b/src/workerd/api/node/tests/url-nodejs-test.js
index ab683c9f..c75fbfad 100644
--- a/src/workerd/api/node/tests/url-nodejs-test.js
+++ b/src/workerd/api/node/tests/url-nodejs-test.js
@@ -77,3 +77,11 @@ export const urlAndSearchParams = {
     );
   },
 };
+
+export const getBuiltinModule = {
+  async test() {
+    const bim = process.getBuiltinModule('node:url');
+    const url = await import('node:url');
+    strictEqual(bim, url.default);
+  }
+};
diff --git a/src/workerd/api/node/tests/url-nodejs-test.wd-test b/src/workerd/api/node/tests/url-nodejs-test.wd-test
index 1be17b89..92589f61 100644
--- a/src/workerd/api/node/tests/url-nodejs-test.wd-test
+++ b/src/workerd/api/node/tests/url-nodejs-test.wd-test
@@ -8,7 +8,7 @@ const unitTests :Workerd.Config = (
           (name = "worker", esModule = embed "url-nodejs-test.js")
         ],
         compatibilityDate = "2023-10-01",
-        compatibilityFlags = ["nodejs_compat"],
+        compatibilityFlags = ["nodejs_compat_v2"],
       )
     ),
   ],