test(peer): cover serve gating dispatch

Add focused serve-side tests for the gates around peer requests. GetGame now has
coverage for the non-catalog, active-operation, and missing-sentinel cases that
should return GameNotFound instead of exposing local files.

The full-file and chunk handlers both depend on the same transfer gate before
touching the QUIC send stream. Extract that gate into a small helper and test
the same cases there, plus the existing local-path exclusion, so both dispatch
paths stay aligned without adding fake QUIC stream plumbing.

Test Plan:
- git diff --check
- just fmt
- just clippy
- just test

Follow-up-Plan: FOLLOW_UP_2.md

crates/lanspread-peer/src/services/stream.rs

@@ -296,6 +296,16 @@ async fn can_serve_game(ctx: &PeerCtx, game_dir: &std::path::Path, game_id: &str
     local_download_available(game_dir, game_id, &active_operations, &catalog).await
 }
 
+async fn can_dispatch_file_transfer(
+    ctx: &PeerCtx,
+    game_dir: &std::path::Path,
+    game_id: &str,
+    relative_path: &str,
+) -> bool {
+    !path_points_inside_local(game_id, relative_path)
+        && can_serve_game(ctx, game_dir, game_id).await
+}
+
 fn path_points_inside_local(game_id: &str, relative_path: &str) -> bool {
     let normalised = relative_path.replace('\\', "/");
     let mut parts = normalised.split('/').filter(|part| !part.is_empty());
@@ -318,9 +328,7 @@ async fn handle_file_data_request(
 
     let mut tx = framed_tx.into_inner();
     let game_dir = ctx.game_dir.read().await.clone();
-    if path_points_inside_local(&desc.game_id, &desc.relative_path)
-        || !can_serve_game(ctx, &game_dir, &desc.game_id).await
-    {
+    if !can_dispatch_file_transfer(ctx, &game_dir, &desc.game_id, &desc.relative_path).await {
         log::info!(
             "Declining GetGameFileData for {} because the game is not currently transferable",
             desc.relative_path
@@ -347,9 +355,7 @@ async fn handle_file_chunk_request(
 
     let mut tx = framed_tx.into_inner();
     let game_dir = ctx.game_dir.read().await.clone();
-    if path_points_inside_local(&game_id, &relative_path)
-        || !can_serve_game(ctx, &game_dir, &game_id).await
-    {
+    if !can_dispatch_file_transfer(ctx, &game_dir, &game_id, &relative_path).await {
         log::info!(
             "Declining GetGameFileChunk for {relative_path} because the game is not currently transferable"
         );
@@ -389,7 +395,87 @@ async fn handle_announce_games(ctx: &PeerCtx, remote_addr: Option<SocketAddr>, g
 
 #[cfg(test)]
 mod tests {
-    use super::path_points_inside_local;
+    use std::{
+        collections::HashSet,
+        path::{Path, PathBuf},
+        sync::{
+            Arc,
+            atomic::{AtomicU64, Ordering},
+        },
+        time::{SystemTime, UNIX_EPOCH},
+    };
+
+    use tokio::sync::{RwLock, mpsc};
+    use tokio_util::{sync::CancellationToken, task::TaskTracker};
+
+    use super::*;
+    use crate::{
+        UnpackFuture,
+        Unpacker,
+        context::{Ctx, OperationKind},
+        peer_db::PeerGameDB,
+    };
+
+    struct TempDir(PathBuf);
+
+    static NEXT_TEMP_ID: AtomicU64 = AtomicU64::new(0);
+
+    impl TempDir {
+        fn new() -> Self {
+            let mut path = std::env::temp_dir();
+            let unique_id = NEXT_TEMP_ID.fetch_add(1, Ordering::Relaxed);
+            path.push(format!(
+                "lanspread-stream-{}-{}-{}",
+                std::process::id(),
+                unique_id,
+                SystemTime::now()
+                    .duration_since(UNIX_EPOCH)
+                    .unwrap_or_default()
+                    .as_nanos()
+            ));
+            std::fs::create_dir_all(&path).expect("temp dir should be created");
+            Self(path)
+        }
+
+        fn path(&self) -> &Path {
+            &self.0
+        }
+    }
+
+    impl Drop for TempDir {
+        fn drop(&mut self) {
+            let _ = std::fs::remove_dir_all(&self.0);
+        }
+    }
+
+    struct NoopUnpacker;
+
+    impl Unpacker for NoopUnpacker {
+        fn unpack<'a>(&'a self, _archive: &'a Path, _dest: &'a Path) -> UnpackFuture<'a> {
+            Box::pin(async { Ok(()) })
+        }
+    }
+
+    fn write_file(path: &Path, bytes: &[u8]) {
+        if let Some(parent) = path.parent() {
+            std::fs::create_dir_all(parent).expect("parent dir should be created");
+        }
+        std::fs::write(path, bytes).expect("file should be written");
+    }
+
+    fn test_ctx(game_dir: PathBuf, catalog: HashSet<String>) -> PeerCtx {
+        let (tx_notify_ui, _rx) = mpsc::unbounded_channel();
+        Ctx::new(
+            Arc::new(RwLock::new(PeerGameDB::new())),
+            "peer".to_string(),
+            game_dir,
+            Arc::new(NoopUnpacker),
+            CancellationToken::new(),
+            TaskTracker::new(),
+            Arc::new(RwLock::new(catalog)),
+        )
+        .to_peer_ctx(tx_notify_ui)
+    }
 
     #[test]
     fn local_relative_paths_are_never_transferable() {
@@ -399,4 +485,99 @@ mod tests {
         assert!(!path_points_inside_local("game", "game/version.ini"));
         assert!(!path_points_inside_local("game", "game/archive.eti"));
     }
+
+    #[tokio::test]
+    async fn get_game_response_respects_serve_gates() {
+        let temp = TempDir::new();
+        write_file(&temp.path().join("ready").join("version.ini"), b"20250101");
+        write_file(
+            &temp.path().join("non-catalog").join("version.ini"),
+            b"20250101",
+        );
+        write_file(&temp.path().join("active").join("version.ini"), b"20250101");
+        std::fs::create_dir_all(temp.path().join("missing-sentinel"))
+            .expect("missing sentinel root should be created");
+
+        let ctx = test_ctx(
+            temp.path().to_path_buf(),
+            HashSet::from([
+                "ready".to_string(),
+                "active".to_string(),
+                "missing-sentinel".to_string(),
+            ]),
+        );
+        ctx.active_operations
+            .write()
+            .await
+            .insert("active".to_string(), OperationKind::Downloading);
+
+        assert!(matches!(
+            get_game_response(&ctx, "ready".to_string()).await,
+            Response::GetGame { id, .. } if id == "ready"
+        ));
+        assert!(matches!(
+            get_game_response(&ctx, "non-catalog".to_string()).await,
+            Response::GameNotFound(id) if id == "non-catalog"
+        ));
+        assert!(matches!(
+            get_game_response(&ctx, "active".to_string()).await,
+            Response::GameNotFound(id) if id == "active"
+        ));
+        assert!(matches!(
+            get_game_response(&ctx, "missing-sentinel".to_string()).await,
+            Response::GameNotFound(id) if id == "missing-sentinel"
+        ));
+    }
+
+    #[tokio::test]
+    async fn file_transfer_dispatch_respects_serve_gates() {
+        let temp = TempDir::new();
+        write_file(&temp.path().join("ready").join("version.ini"), b"20250101");
+        write_file(
+            &temp.path().join("non-catalog").join("version.ini"),
+            b"20250101",
+        );
+        write_file(&temp.path().join("active").join("version.ini"), b"20250101");
+        std::fs::create_dir_all(temp.path().join("missing-sentinel"))
+            .expect("missing sentinel root should be created");
+
+        let ctx = test_ctx(
+            temp.path().to_path_buf(),
+            HashSet::from([
+                "ready".to_string(),
+                "active".to_string(),
+                "missing-sentinel".to_string(),
+            ]),
+        );
+        ctx.active_operations
+            .write()
+            .await
+            .insert("active".to_string(), OperationKind::Downloading);
+
+        assert!(can_dispatch_file_transfer(&ctx, temp.path(), "ready", "ready/version.ini").await);
+        assert!(
+            !can_dispatch_file_transfer(
+                &ctx,
+                temp.path(),
+                "non-catalog",
+                "non-catalog/version.ini",
+            )
+            .await
+        );
+        assert!(
+            !can_dispatch_file_transfer(&ctx, temp.path(), "active", "active/version.ini").await
+        );
+        assert!(
+            !can_dispatch_file_transfer(
+                &ctx,
+                temp.path(),
+                "missing-sentinel",
+                "missing-sentinel/archive.eti",
+            )
+            .await
+        );
+        assert!(
+            !can_dispatch_file_transfer(&ctx, temp.path(), "ready", "ready/local/save.dat").await
+        );
+    }
 }