make item enums non_exhaustive

CHANGELOG.md

@@ -12,6 +12,8 @@
     `retina::PacketContext`. Both must be printed to provide the same
     information as before. This change reduces how much data needs to be copied
     with each packet.
+*   BREAKING: `PacketItem` and `CodecItem` are now `#[non_exhaustive]` for
+    future expansion.
 
 ## `v0.3.9` (2022-04-12)
 

src/client/mod.rs

@@ -1796,6 +1796,7 @@ async fn punch_firewall_hole(
 
 /// An item yielded by [`Session<Playing>`]'s [`futures::stream::Stream`] impl.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum PacketItem {
     RtpPacket(rtp::Packet),
     SenderReport(rtp::SenderReport),

src/codec/mod.rs

@@ -26,6 +26,7 @@ pub(crate) mod simple_audio;
 
 /// An item yielded from [`crate::client::Demuxed`]'s [`futures::stream::Stream`] impl.
 #[derive(Debug)]
+#[non_exhaustive]
 pub enum CodecItem {
     VideoFrame(VideoFrame),
     AudioFrame(AudioFrame),