fix(ext/node): hostname is valid IPv4 addr (#23243)

Fixes `docusaurus serve`

2 files changed, 7 insertions, 2 deletions

diff --git a/ext/node/polyfills/http.ts b/ext/node/polyfills/http.ts
index 933a8dbcd..67981e8de 100644
--- a/ext/node/polyfills/http.ts
+++ b/ext/node/polyfills/http.ts
@@ -1653,7 +1653,10 @@ export class ServerImpl extends EventEmitter {
 
     // TODO(bnoordhuis) Node prefers [::] when host is omitted,
     // we on the other hand default to 0.0.0.0.
-    const hostname = options.host ?? "0.0.0.0";
+    let hostname = options.host ?? "0.0.0.0";
+    if (hostname == "localhost") {
+      hostname = "127.0.0.1";
+    }
     this.#addr = {
       hostname,
       port,
diff --git a/tests/unit_node/http_test.ts b/tests/unit_node/http_test.ts
index 57ade6298..049cdbbbc 100644
--- a/tests/unit_node/http_test.ts
+++ b/tests/unit_node/http_test.ts
@@ -27,7 +27,9 @@ Deno.test("[node/http listen]", async () => {
     const { promise, resolve } = Promise.withResolvers<void>();
     const server = http.createServer();
 
-    server.listen(() => {
+    server.listen(42453, "localhost", () => {
+      // @ts-ignore address() is not a string
+      assertEquals(server.address()!.address, "127.0.0.1");
       server.close();
     });
     server.on("close", () => {