From 4a66a5e2650932ada8e6631cec4df84082570b3a Mon Sep 17 00:00:00 2001
From: Carolina <79524656+carochacs@users.noreply.github.com>
Date: Sat, 1 Aug 2026 15:31:57 -0600
Subject: [PATCH 1/4] Add regression for failed sloppak websocket load

---
 lib/routers/ws_highway.py                    |  4 ++
 tests/test_highway_ws_failed_sloppak_load.py | 63 ++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 tests/test_highway_ws_failed_sloppak_load.py

diff --git a/lib/routers/ws_highway.py b/lib/routers/ws_highway.py
index fd1ad602..a73faff9 100644
--- a/lib/routers/ws_highway.py
+++ b/lib/routers/ws_highway.py
@@ -212,6 +212,10 @@ async def _send_keepalives():
                     None,
                     lambda: _ctx.run(sloppak_mod.load_song, filename, dlc, appstate.sloppak_cache_dir),
                 )
+                if loaded_slop is None:
+                    await websocket.send_json({"error": "Failed to load sloppak"})
+                    await websocket.close()
+                    return
                 song = loaded_slop.song
                 tmp = str(loaded_slop.source_dir)
                 owns_tmp = False
diff --git a/tests/test_highway_ws_failed_sloppak_load.py b/tests/test_highway_ws_failed_sloppak_load.py
new file mode 100644
index 00000000..cd6ba64f
--- /dev/null
+++ b/tests/test_highway_ws_failed_sloppak_load.py
@@ -0,0 +1,63 @@
+"""Regression coverage for sloppak load failures in the highway websocket."""
+
+import asyncio
+import importlib
+import sys
+
+import pytest
+
+
+class _CapturingWS:
+    def __init__(self):
+        self.messages = []
+        self.accepted = False
+        self.closed = False
+
+    async def accept(self):
+        self.accepted = True
+
+    async def send_json(self, data):
+        self.messages.append(data)
+
+    async def receive_text(self):
+        await asyncio.sleep(0)
+        return ""
+
+    async def close(self):
+        self.closed = True
+
+
+@pytest.fixture()
+def server(tmp_path, monkeypatch):
+    (tmp_path / "dlc").mkdir()
+    monkeypatch.setenv("CONFIG_DIR", str(tmp_path / "config"))
+    monkeypatch.setenv("DLC_DIR", str(tmp_path / "dlc"))
+    monkeypatch.setenv("FEEDBACK_SKIP_STARTUP_TASKS", "1")
+    sys.modules.pop("server", None)
+    mod = importlib.import_module("server")
+    yield mod, tmp_path / "dlc", tmp_path / "cache"
+    conn = getattr(getattr(mod, "meta_db", None), "conn", None)
+    if conn is not None:
+        getattr(mod, "_join_background_db_threads", lambda: None)()
+        conn.close()
+    sys.modules.pop("server", None)
+
+
+def test_sloppak_loader_returning_none_sends_error_without_touching_stems(
+    server, monkeypatch
+):
+    _server, dlc, cache = server
+    (dlc / "broken.feedpak").mkdir()
+
+    import appstate
+    from routers import ws_highway
+
+    monkeypatch.setattr(appstate, "sloppak_cache_dir", cache)
+    monkeypatch.setattr(ws_highway.sloppak_mod, "load_song", lambda *a, **kw: None)
+
+    ws = _CapturingWS()
+    asyncio.run(ws_highway.highway_ws(ws, "broken.feedpak", arrangement=0))
+
+    assert ws.accepted is True
+    assert ws.closed is True
+    assert {"error": "Failed to load sloppak"} in ws.messages

From e2614a8a81511a61728922534a004966b3fddee8 Mon Sep 17 00:00:00 2001
From: Carolina <79524656+carochacs@users.noreply.github.com>
Date: Sun, 2 Aug 2026 11:20:21 -0600
Subject: [PATCH 2/4] Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Carolina <79524656+carochacs@users.noreply.github.com>
---
 lib/routers/ws_highway.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/routers/ws_highway.py b/lib/routers/ws_highway.py
index a73faff9..fae2dd3e 100644
--- a/lib/routers/ws_highway.py
+++ b/lib/routers/ws_highway.py
@@ -213,6 +213,8 @@ async def _send_keepalives():
                     lambda: _ctx.run(sloppak_mod.load_song, filename, dlc, appstate.sloppak_cache_dir),
                 )
                 if loaded_slop is None:
+                    _keepalive_active = False
+                    keepalive_task.cancel()
                     await websocket.send_json({"error": "Failed to load sloppak"})
                     await websocket.close()
                     return

From 7a36467e9d464bd07c1ac2be1ef1902a04f83b47 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Mon, 3 Aug 2026 05:39:57 +0000
Subject: [PATCH 3/4] Strengthen regression test and add CHANGELOG entry
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- test_highway_ws_failed_sloppak_load.py: assert the exact two-frame
  message sequence and a single close() call, not just that the error
  was somewhere in the messages list — a handler that sends the error
  and keeps processing would previously still pass (CodeRabbit).
- CHANGELOG.md: add the [Unreleased] Fixed entry for this bug, per the
  PR template checklist.
---
 CHANGELOG.md                                 | 9 +++++++++
 tests/test_highway_ws_failed_sloppak_load.py | 8 +++++++-
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c262781..212d1912 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+- **Failed sloppak loads at the highway websocket no longer crash on a `None` song.**
+  When `sloppak_mod.load_song()` returns `None` (cache corruption, partial
+  extraction, etc.), the handler previously dereferenced `loaded_slop.song`
+  before any guard existed, crashing the connection instead of reporting the
+  failure. The load-failure guard now sits immediately after the load call —
+  the handler sends a `Failed to load sloppak` error and closes the socket
+  instead of continuing into arrangement/stem access with a `None` song.
+
 ### Added
 - **Core reader for source rigs (feedpak 1.18.0).** A pack can declare what a
   MIDI part should sound like by binding a rig; core now reads that binding and
diff --git a/tests/test_highway_ws_failed_sloppak_load.py b/tests/test_highway_ws_failed_sloppak_load.py
index cd6ba64f..d3e859cd 100644
--- a/tests/test_highway_ws_failed_sloppak_load.py
+++ b/tests/test_highway_ws_failed_sloppak_load.py
@@ -12,6 +12,7 @@ def __init__(self):
         self.messages = []
         self.accepted = False
         self.closed = False
+        self.close_calls = 0
 
     async def accept(self):
         self.accepted = True
@@ -24,6 +25,7 @@ async def receive_text(self):
         return ""
 
     async def close(self):
+        self.close_calls += 1
         self.closed = True
 
 
@@ -60,4 +62,8 @@ def test_sloppak_loader_returning_none_sends_error_without_touching_stems(
 
     assert ws.accepted is True
     assert ws.closed is True
-    assert {"error": "Failed to load sloppak"} in ws.messages
+    assert ws.close_calls == 1
+    assert ws.messages == [
+        {"type": "loading", "stage": "Extracting..."},
+        {"error": "Failed to load sloppak"},
+    ]

From 2ae2dc7f434c49c1ff0363d38df7eed83ed5fe39 Mon Sep 17 00:00:00 2001
From: Carolina <79524656+carochacs@users.noreply.github.com>
Date: Tue, 4 Aug 2026 22:03:15 -0600
Subject: [PATCH 4/4] Fix changelog heading spacing

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 212d1912..457a410c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Fixed
+
 - **Failed sloppak loads at the highway websocket no longer crash on a `None` song.**
   When `sloppak_mod.load_song()` returns `None` (cache corruption, partial
   extraction, etc.), the handler previously dereferenced `loaded_slop.song`