Refresh workers on same-path project rebinding

3 files changed, 69 insertions, 3 deletions

diff --git a/crates/fidget-spinner-cli/src/mcp/host/process.rs b/crates/fidget-spinner-cli/src/mcp/host/process.rs
index d4cbb4b..fdbd873 100644
--- a/crates/fidget-spinner-cli/src/mcp/host/process.rs
+++ b/crates/fidget-spinner-cli/src/mcp/host/process.rs
@@ -55,6 +55,11 @@ impl WorkerSupervisor {
         self.bound_project_root = Some(project_root);
     }
 
+    pub(super) fn refresh_binding(&mut self, project_root: PathBuf) {
+        self.kill_current_worker();
+        self.bound_project_root = Some(project_root);
+    }
+
     pub(super) fn execute(
         &mut self,
         request_id: HostRequestId,
diff --git a/crates/fidget-spinner-cli/src/mcp/host/runtime.rs b/crates/fidget-spinner-cli/src/mcp/host/runtime.rs
index bf0484a..f2f10b7 100644
--- a/crates/fidget-spinner-cli/src/mcp/host/runtime.rs
+++ b/crates/fidget-spinner-cli/src/mcp/host/runtime.rs
@@ -392,7 +392,8 @@ impl HostRuntime {
                 let args = deserialize::<ProjectBindArgs>(arguments, "tools/call:project.bind")?;
                 let resolved = resolve_project_binding(PathBuf::from(args.path))
                     .map_err(host_store_fault("tools/call:project.bind"))?;
-                self.worker.rebind(resolved.binding.project_root.clone());
+                self.worker
+                    .refresh_binding(resolved.binding.project_root.clone());
                 self.binding = Some(resolved.binding);
                 tool_success(
                     project_bind_output(&resolved.status)?,
diff --git a/crates/fidget-spinner-cli/tests/mcp_hardening.rs b/crates/fidget-spinner-cli/tests/mcp_hardening.rs
index fad4937..fc744c5 100644
--- a/crates/fidget-spinner-cli/tests/mcp_hardening.rs
+++ b/crates/fidget-spinner-cli/tests/mcp_hardening.rs
@@ -7,8 +7,8 @@ use std::path::PathBuf;
 use std::process::{Child, ChildStdin, ChildStdout, Command, Stdio};
 
 use camino::Utf8PathBuf;
-use fidget_spinner_core::NonEmptyText;
-use fidget_spinner_store_sqlite::ProjectStore;
+use fidget_spinner_core::{NonEmptyText, Slug};
+use fidget_spinner_store_sqlite::{CreateFrontierRequest, ProjectStore};
 use libmcp as _;
 use maud as _;
 use percent_encoding as _;
@@ -199,6 +199,15 @@ fn tool_names(response: &Value) -> Vec<&str> {
         .collect()
 }
 
+fn frontier_slugs(response: &Value) -> Vec<&str> {
+    tool_content(response)["frontiers"]
+        .as_array()
+        .into_iter()
+        .flatten()
+        .filter_map(|frontier| frontier["slug"].as_str())
+        .collect()
+}
+
 #[test]
 fn cold_start_exposes_bound_surface_and_new_toolset() -> TestResult {
     let project_root = temp_project_root("cold_start")?;
@@ -596,3 +605,54 @@ fn experiment_close_drives_metric_best_and_analysis() -> TestResult {
     );
     Ok(())
 }
+
+#[test]
+fn same_path_project_bind_refreshes_destructive_reseed() -> TestResult {
+    let project_root = temp_project_root("same_path_reseed")?;
+
+    let mut harness = McpHarness::spawn(None)?;
+    let _ = harness.initialize()?;
+    harness.notify_initialized()?;
+
+    let bind = harness.bind_project(60, &project_root)?;
+    assert_tool_ok(&bind);
+
+    assert_tool_ok(&harness.call_tool(
+        61,
+        "frontier.create",
+        json!({
+            "label": "alpha frontier",
+            "objective": "first seeded frontier",
+            "slug": "alpha",
+        }),
+    )?);
+    let alpha_list = harness.call_tool_full(62, "frontier.list", json!({}))?;
+    assert_tool_ok(&alpha_list);
+    assert_eq!(frontier_slugs(&alpha_list), vec!["alpha"]);
+
+    must(
+        fs::remove_dir_all(project_root.join(fidget_spinner_store_sqlite::STORE_DIR_NAME)),
+        "remove project store",
+    )?;
+    init_project(&project_root)?;
+    let mut reopened = must(ProjectStore::open(&project_root), "open recreated store")?;
+    let _beta = must(
+        reopened.create_frontier(CreateFrontierRequest {
+            label: must(NonEmptyText::new("beta frontier"), "beta label")?,
+            objective: must(
+                NonEmptyText::new("second seeded frontier"),
+                "beta objective",
+            )?,
+            slug: Some(must(Slug::new("beta"), "beta slug")?),
+        }),
+        "create beta frontier directly in recreated store",
+    )?;
+
+    let rebind = harness.bind_project(63, &project_root)?;
+    assert_tool_ok(&rebind);
+
+    let beta_list = harness.call_tool_full(64, "frontier.list", json!({}))?;
+    assert_tool_ok(&beta_list);
+    assert_eq!(frontier_slugs(&beta_list), vec!["beta"]);
+    Ok(())
+}