Fallback stable socket listener to a user-scoped path (#1351)

* Fallback stable socket listener to user socket path

* Move stable socket path out of /tmp

* Keep socket health checks active on fallback paths

---------

Co-authored-by: Lawrence Chen <lawrencecchen@users.noreply.github.com>

tests_v2/cmux.py

@@ -19,6 +19,7 @@ Notes:
 
 import base64
 import errno
+import glob
 import json
 import os
 import select
@@ -32,16 +33,53 @@ class cmuxError(Exception):
     """Exception raised for cmux errors."""
 
 
+_APP_SUPPORT_DIR = os.path.expanduser("~/Library/Application Support/cmux")
+_STABLE_SOCKET_PATH = os.path.join(_APP_SUPPORT_DIR, "cmux.sock")
+_LEGACY_STABLE_SOCKET_PATH = "/tmp/cmux.sock"
+_LAST_SOCKET_PATH_FILES = [
+    os.path.join(_APP_SUPPORT_DIR, "last-socket-path"),
+    "/tmp/cmux-last-socket-path",
+]
+
+
+def _read_last_socket_path() -> Optional[str]:
+    for marker_path in _LAST_SOCKET_PATH_FILES:
+        try:
+            with open(marker_path, "r", encoding="utf-8") as f:
+                path = f.read().strip()
+            if path:
+                return path
+        except OSError:
+            continue
+    return None
+
+
 def _default_socket_path() -> str:
     # Backwards/forward compatibility: some scripts export CMUX_SOCKET,
     # while the client historically used CMUX_SOCKET_PATH.
     override = os.environ.get("CMUX_SOCKET_PATH") or os.environ.get("CMUX_SOCKET")
     if override:
-        return override
-    candidates = ["/tmp/cmux-debug.sock", "/tmp/cmux.sock"]
+        if os.path.exists(override):
+            return override
+        if override not in {_STABLE_SOCKET_PATH, _LEGACY_STABLE_SOCKET_PATH}:
+            return override
+
+    last_socket = _read_last_socket_path()
+    if last_socket and os.path.exists(last_socket):
+        return last_socket
+
+    candidates = ["/tmp/cmux-debug.sock", _STABLE_SOCKET_PATH, _LEGACY_STABLE_SOCKET_PATH]
     for path in candidates:
         if os.path.exists(path):
             return path
+
+    discovered = glob.glob("/tmp/cmux-debug-*.sock")
+    discovered.extend(glob.glob(os.path.join(_APP_SUPPORT_DIR, "cmux*.sock")))
+    discovered = [path for path in discovered if os.path.exists(path)]
+    if discovered:
+        discovered.sort(key=os.path.getmtime, reverse=True)
+        return discovered[0]
+
     return candidates[0]
 
 

tests_v2/test_cpu_notifications.py

@@ -227,7 +227,11 @@ def main():
     print(f"\nFound cmux process: PID {pid}")
 
     # Try to connect to the socket
-    socket_paths = ["/tmp/cmux.sock", "/tmp/cmux-debug.sock"]
+    socket_paths = [
+        os.path.expanduser("~/Library/Application Support/cmux/cmux.sock"),
+        "/tmp/cmux.sock",
+        "/tmp/cmux-debug.sock",
+    ]
     client = None
     for socket_path in socket_paths:
         if os.path.exists(socket_path):

tests_v2/test_ctrl_enter_keybind.py

@@ -31,7 +31,7 @@ def infer_app_name_for_osascript(socket_path: str) -> str:
     Examples:
       - /tmp/cmux-debug.sock          -> "cmux DEV"
       - /tmp/cmux-debug-foo.sock      -> "cmux DEV foo"
-      - /tmp/cmux.sock                -> "cmux"
+      - ~/Library/Application Support/cmux/cmux.sock -> "cmux"
       - /tmp/cmux-foo.sock            -> "cmux foo"
     """
     base = Path(socket_path).name