fix(acp): normalize Windows cwd for WSL tool execution

acp_adapter/session.py

@@ -26,6 +26,33 @@ from typing import Any, Dict, List, Optional
 logger = logging.getLogger(__name__)
 
 
+def _win_path_to_wsl(path: str) -> str | None:
+    """Convert a Windows drive path to its WSL /mnt/<drive>/... equivalent."""
+    match = re.match(r"^([A-Za-z]):[\\/](.*)$", path)
+    if not match:
+        return None
+    drive = match.group(1).lower()
+    tail = match.group(2).replace("\\", "/")
+    return f"/mnt/{drive}/{tail}"
+
+
+def _translate_acp_cwd(cwd: str) -> str:
+    """Translate Windows ACP cwd values when Hermes itself is running in WSL.
+
+    Windows ACP clients can launch ``hermes acp`` inside WSL while still sending
+    editor workspaces as Windows drive paths such as ``E:\\Projects``. Store
+    and execute against the WSL mount path so agents, tools, and persisted ACP
+    sessions all agree on the usable workspace. Native Linux/macOS keeps the
+    original cwd unchanged.
+    """
+    from hermes_constants import is_wsl
+
+    if not is_wsl():
+        return cwd
+    translated = _win_path_to_wsl(str(cwd))
+    return translated if translated is not None else cwd
+
+
 def _normalize_cwd_for_compare(cwd: str | None) -> str:
     raw = str(cwd or ".").strip()
     if not raw:
@@ -34,11 +61,9 @@ def _normalize_cwd_for_compare(cwd: str | None) -> str:
 
     # Normalize Windows drive paths into the equivalent WSL mount form so
     # ACP history filters match the same workspace across Windows and WSL.
-    match = re.match(r"^([A-Za-z]):[\\/](.*)$", expanded)
-    if match:
-        drive = match.group(1).lower()
-        tail = match.group(2).replace("\\", "/")
-        expanded = f"/mnt/{drive}/{tail}"
+    translated = _win_path_to_wsl(expanded)
+    if translated is not None:
+        expanded = translated
     elif re.match(r"^/mnt/[A-Za-z]/", expanded):
         expanded = f"/mnt/{expanded[5].lower()}/{expanded[7:]}"
 
@@ -96,12 +121,18 @@ def _acp_stderr_print(*args, **kwargs) -> None:
 
 
 def _register_task_cwd(task_id: str, cwd: str) -> None:
-    """Bind a task/session id to the editor's working directory for tools."""
+    """Bind a task/session id to the editor's working directory for tools.
+
+    Zed can launch Hermes from a Windows workspace while the ACP process runs
+    inside WSL. In that case ACP sends cwd as e.g. ``E:\\Projects\\POTI``;
+    local tools need the WSL mount equivalent or subprocess creation fails
+    before the command can run.
+    """
     if not task_id:
         return
     try:
         from tools.terminal_tool import register_task_env_overrides
-        register_task_env_overrides(task_id, {"cwd": cwd})
+        register_task_env_overrides(task_id, {"cwd": _translate_acp_cwd(cwd)})
     except Exception:
         logger.debug("Failed to register ACP task cwd override", exc_info=True)
 
@@ -180,6 +211,7 @@ class SessionManager:
         """Create a new session with a unique ID and a fresh AIAgent."""
         import threading
 
+        cwd = _translate_acp_cwd(cwd)
         session_id = str(uuid.uuid4())
         agent = self._make_agent(session_id=session_id, cwd=cwd)
         state = SessionState(
@@ -222,6 +254,7 @@ class SessionManager:
         """Deep-copy a session's history into a new session."""
         import threading
 
+        cwd = _translate_acp_cwd(cwd)
         original = self.get_session(session_id)  # checks DB too
         if original is None:
             return None
@@ -323,6 +356,7 @@ class SessionManager:
 
     def update_cwd(self, session_id: str, cwd: str) -> Optional[SessionState]:
         """Update the working directory for a session and its tool overrides."""
+        cwd = _translate_acp_cwd(cwd)
         state = self.get_session(session_id)  # checks DB too
         if state is None:
             return None

tests/acp/test_session.py

@@ -8,6 +8,7 @@ from types import SimpleNamespace
 import pytest
 from unittest.mock import MagicMock, patch
 
+from acp_adapter import session as acp_session
 from acp_adapter.session import SessionManager, SessionState
 from hermes_state import SessionDB
 
@@ -42,6 +43,27 @@ class TestCreateSession:
         state = manager.create_session(cwd="/tmp/work")
         assert calls == [(state.session_id, "/tmp/work")]
 
+
+    def test_register_task_cwd_translates_windows_drive_for_wsl_tools(self, monkeypatch):
+        captured = {}
+
+        def fake_register_task_env_overrides(task_id, overrides):
+            captured["task_id"] = task_id
+            captured["overrides"] = overrides
+
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+        monkeypatch.setattr(
+            "tools.terminal_tool.register_task_env_overrides",
+            fake_register_task_env_overrides,
+        )
+
+        acp_session._register_task_cwd("session-1", r"E:\Projects\AI\paperclip")
+
+        assert captured == {
+            "task_id": "session-1",
+            "overrides": {"cwd": "/mnt/e/Projects/AI/paperclip"},
+        }
+
     def test_session_ids_are_unique(self, manager):
         s1 = manager.create_session()
         s2 = manager.create_session()
@@ -56,6 +78,59 @@ class TestCreateSession:
         assert manager.get_session("does-not-exist") is None
 
 
+
+
+# ---------------------------------------------------------------------------
+# WSL cwd translation
+# ---------------------------------------------------------------------------
+
+
+class TestWslCwdTranslation:
+    def test_translate_acp_cwd_converts_windows_drive_path_when_wsl(self, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+
+        assert acp_session._translate_acp_cwd(r"E:\Projects\AI\paperclip") == "/mnt/e/Projects/AI/paperclip"
+
+    def test_translate_acp_cwd_handles_forward_slashes_when_wsl(self, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+
+        assert acp_session._translate_acp_cwd("D:/work/project") == "/mnt/d/work/project"
+
+    def test_translate_acp_cwd_leaves_windows_drive_path_unchanged_off_wsl(self, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", False)
+
+        assert acp_session._translate_acp_cwd(r"E:\Projects\AI\paperclip") == r"E:\Projects\AI\paperclip"
+
+    def test_translate_acp_cwd_leaves_posix_path_unchanged_on_wsl(self, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+
+        assert acp_session._translate_acp_cwd("/mnt/e/Projects/AI/paperclip") == "/mnt/e/Projects/AI/paperclip"
+
+    def test_create_session_stores_translated_cwd_on_wsl(self, manager, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+
+        state = manager.create_session(cwd=r"E:\Projects\AI\paperclip")
+
+        assert state.cwd == "/mnt/e/Projects/AI/paperclip"
+
+    def test_fork_session_stores_translated_cwd_on_wsl(self, manager, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+        original = manager.create_session(cwd="/tmp/base")
+
+        forked = manager.fork_session(original.session_id, cwd=r"D:\work\project")
+
+        assert forked is not None
+        assert forked.cwd == "/mnt/d/work/project"
+
+    def test_update_cwd_stores_translated_cwd_on_wsl(self, manager, monkeypatch):
+        monkeypatch.setattr("hermes_constants._wsl_detected", True)
+        state = manager.create_session(cwd="/tmp/old")
+
+        updated = manager.update_cwd(state.session_id, cwd=r"C:\Users\foo\project")
+
+        assert updated is not None
+        assert updated.cwd == "/mnt/c/Users/foo/project"
+
 # ---------------------------------------------------------------------------
 # fork
 # ---------------------------------------------------------------------------