fix: net listen crashes on explicit undefined hostname (#7706)

2 files changed, 13 insertions, 2 deletions

diff --git a/cli/rt/30_net.js b/cli/rt/30_net.js
index 53de5200d..9a71f0693 100644
--- a/cli/rt/30_net.js
+++ b/cli/rt/30_net.js
@@ -203,10 +203,10 @@
     }
   }
 
-  function listen(options) {
+  function listen({ hostname, ...options }) {
     const res = opListen({
       transport: "tcp",
-      hostname: "0.0.0.0",
+      hostname: typeof hostname === "undefined" ? "0.0.0.0" : hostname,
       ...options,
     });
 
diff --git a/cli/tests/unit/net_test.ts b/cli/tests/unit/net_test.ts
index 2c6134318..8eaabdbba 100644
--- a/cli/tests/unit/net_test.ts
+++ b/cli/tests/unit/net_test.ts
@@ -533,3 +533,14 @@ unitTest(
     await resolvable;
   },
 );
+
+unitTest(
+  {
+    perms: { net: true },
+  },
+  function netExplicitUndefinedHostname() {
+    const listener = Deno.listen({ hostname: undefined, port: 8080 });
+    assertEquals((listener.addr as Deno.NetAddr).hostname, "0.0.0.0");
+    listener.close();
+  },
+);