fix(ui): bind sessions to repo path

coding-agent/src/coding_agent/ui/session_manager.py

@@ -52,6 +52,7 @@
 logger = logging.getLogger(__name__)
 
 _CHECKPOINT_SESSION_CONFIG_KEY = "session_restart_config"
+_DEFAULT_EXECUTION_BINDING = object()
 T = TypeVar("T")
 
 
@@ -97,20 +98,19 @@ async def complete(self, messages: list[dict[str, Any]]) -> str:
 class Session:
     """A managed agent session.
 
-    Note: ``repo_path`` is legacy/backward-compat metadata only;
-    ``execution_binding`` is the authoritative workspace contract.
+    Note: ``execution_binding`` is the authoritative workspace contract.
+    ``repo_path`` remains backward-compatible metadata and supplies the
+    default local workspace root when no explicit execution binding is provided.
     """
 
     id: str
     created_at: datetime
     last_activity: datetime
     wire: LocalWire = field(init=False)
     approval_store: ApprovalStore = field(default_factory=ApprovalStore)
-    repo_path: Path | None = None  # legacy/backward-compat metadata only
-    execution_binding: ExecutionBinding = field(
-        default_factory=lambda: LocalExecutionBinding(
-            workspace_root=str(Path.cwd().resolve())
-        )
+    repo_path: Path | None = None  # legacy metadata; seeds default local binding
+    execution_binding: ExecutionBinding = field(  # type: ignore[assignment]
+        default=cast(ExecutionBinding, _DEFAULT_EXECUTION_BINDING),
     )
     approval_policy: ApprovalPolicy = ApprovalPolicy.AUTO
     provider: Any | None = None
@@ -131,6 +131,15 @@ class Session:
     approval_coordinator: ApprovalCoordinator = field(init=False)
 
     def __post_init__(self) -> None:
+        if self.execution_binding is cast(ExecutionBinding, _DEFAULT_EXECUTION_BINDING):
+            workspace_root = (
+                str(self.repo_path.resolve())
+                if self.repo_path is not None
+                else str(Path.cwd().resolve())
+            )
+            self.execution_binding = LocalExecutionBinding(
+                workspace_root=workspace_root
+            )
         self.wire = LocalWire(self.id)
         self.approval_coordinator = ApprovalCoordinator(self.approval_store)
 
@@ -148,8 +157,8 @@ def to_store_data(self) -> dict[str, Any]:
             "id": self.id,
             "created_at": self.created_at.isoformat(),
             "last_activity": self.last_activity.isoformat(),
-            # repo_path is legacy/backward-compat metadata; execution_binding is
-            # the authoritative workspace contract.
+            # repo_path remains backward-compatible metadata and seeds the
+            # default local binding when execution_binding is omitted.
             "repo_path": None if self.repo_path is None else str(self.repo_path),
             "execution_binding": self.execution_binding.to_dict(),
             "approval_policy": self.approval_policy.value,
@@ -187,7 +196,9 @@ def from_store_data(cls, data: dict[str, Any]) -> Session:
             execution_binding = ExecutionBinding.from_dict(binding_raw)
         else:
             workspace_root = (
-                repo_path_raw if repo_path_raw is not None else str(Path.cwd())
+                str(Path(repo_path_raw).resolve())
+                if repo_path_raw is not None
+                else str(Path.cwd().resolve())
             )
             execution_binding = LocalExecutionBinding(workspace_root=workspace_root)
         session = cls(

coding-agent/tests/ui/test_session_manager_public_api.py

@@ -178,6 +178,40 @@ def test_session_metadata_round_trips_local_execution_binding(tmp_path: Path) ->
     assert reloaded.execution_binding.workspace_root == str(bound_repo)
 
 
+def test_session_defaults_local_execution_binding_from_repo_path(
+    tmp_path: Path,
+) -> None:
+    bound_repo = tmp_path / "bound-repo"
+    session = Session(
+        id="binding-from-repo-path",
+        created_at=datetime.now(),
+        last_activity=datetime.now(),
+        approval_store=ApprovalStore(),
+        repo_path=bound_repo,
+    )
+
+    assert isinstance(session.execution_binding, LocalExecutionBinding)
+    assert session.execution_binding.workspace_root == str(bound_repo.resolve())
+
+
+def test_session_preserves_explicit_execution_binding_with_repo_path(
+    tmp_path: Path,
+) -> None:
+    bound_repo = tmp_path / "bound-repo"
+    explicit_root = tmp_path / "explicit-root"
+    session = Session(
+        id="explicit-binding-wins",
+        created_at=datetime.now(),
+        last_activity=datetime.now(),
+        approval_store=ApprovalStore(),
+        repo_path=bound_repo,
+        execution_binding=LocalExecutionBinding(workspace_root=str(explicit_root)),
+    )
+
+    assert isinstance(session.execution_binding, LocalExecutionBinding)
+    assert session.execution_binding.workspace_root == str(explicit_root)
+
+
 def test_session_metadata_defaults_missing_binding_to_local_from_repo_path(
     tmp_path: Path,
 ) -> None:
@@ -207,6 +241,37 @@ def test_session_metadata_defaults_missing_binding_to_local_from_repo_path(
     assert reloaded.execution_binding.workspace_root == str(legacy_repo)
 
 
+def test_session_metadata_defaults_missing_binding_resolves_relative_repo_path(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    store = InMemorySessionStore()
+    created_at = datetime.now()
+    last_activity = datetime.now()
+    legacy_repo = tmp_path / "legacy-repo"
+    legacy_repo.mkdir()
+    monkeypatch.chdir(tmp_path)
+    store.save(
+        "legacy-relative-session",
+        {
+            "id": "legacy-relative-session",
+            "created_at": created_at.isoformat(),
+            "last_activity": last_activity.isoformat(),
+            "repo_path": "legacy-repo",
+            "approval_policy": "auto",
+            "provider_name": None,
+            "model_name": None,
+            "base_url": None,
+            "max_steps": 30,
+            "tape_id": None,
+        },
+    )
+
+    reloaded = SessionManager(store=store).get_session("legacy-relative-session")
+
+    assert isinstance(reloaded.execution_binding, LocalExecutionBinding)
+    assert reloaded.execution_binding.workspace_root == str(legacy_repo.resolve())
+
+
 def test_event_queue_mutations_do_not_persist_sync_runtime_only_state() -> None:
     manager = SessionManager(store=InMemorySessionStore())
     session = Session(