resolve #1347 addresses issue of no metadata on identity frame

src/stream.cpp

@@ -255,6 +255,12 @@ bool zmq::stream_t::xhas_in ()
     blob_t identity = pipe->get_identity ();
     rc = prefetched_id.init_size (identity.size ());
     errno_assert (rc == 0);
+
+    // forward metadata (if any)
+    metadata_t *metadata = prefetched_msg.metadata();
+    if (metadata)
+        prefetched_id.set_metadata(metadata);
+
     memcpy (prefetched_id.data (), identity.data (), identity.size ());
     prefetched_id.set_flags (msg_t::more);
 

tests/test_stream.cpp

@@ -88,6 +88,9 @@ test_stream_to_dealer (void)
     rc = zmq_recv (stream, buffer, 255, 0);
     assert (rc == 0);
 
+    // Verify the existence of Peer-Address metadata
+    assert (streq (zmq_msg_gets (&identity, "Peer-Address"), "127.0.0.1"));
+
     //  Real data follows
     //  First frame is identity
     rc = zmq_msg_recv (&identity, stream, 0);