fix(web): picking a branch in a subfolder project keeps the thread in the project folder

apps/web/src/components/BranchToolbar.logic.test.ts

@@ -177,20 +177,27 @@ describe("resolveBranchSelectionTarget", () => {
   });
 
   it("switches back to the main repo when the ref already lives there", () => {
-    expect(
-      resolveBranchSelectionTarget({
-        activeProjectCwd: "/repo",
-        activeWorktreePath: "/repo/.t3/worktrees/feature-a",
-        refName: {
-          isDefault: true,
-          worktreePath: "/repo",
-        },
-      }),
-    ).toEqual({
-      checkoutCwd: "/repo",
-      nextWorktreePath: null,
-      reuseExistingWorktree: true,
-    });
+    // A subdirectory project's own checkout is reported at the repository root.
+    for (const [activeProjectCwd, activeWorktreePath] of [
+      ["/repo", "/repo/.t3/worktrees/feature-a"],
+      ["/repo/packages/app", "/repo/.t3/worktrees/feature-a"],
+      ["/repo/packages/app", null],
+    ] as const) {
+      expect(
+        resolveBranchSelectionTarget({
+          activeProjectCwd,
+          activeWorktreePath,
+          refName: {
+            isDefault: true,
+            worktreePath: "/repo",
+          },
+        }),
+      ).toEqual({
+        checkoutCwd: "/repo",
+        nextWorktreePath: null,
+        reuseExistingWorktree: true,
+      });
+    }
   });
 
   it("keeps checkout in the current worktree for non-default refs", () => {

apps/web/src/components/BranchToolbar.logic.ts

@@ -7,6 +7,7 @@ import type {
 } from "@t3tools/contracts";
 import * as Schema from "effect/Schema";
 import { sanitizeNewRefName } from "@t3tools/shared/git";
+import { workspaceRelativeFilePath } from "@t3tools/shared/path";
 import { toSortableTimestamp } from "@t3tools/client-runtime/state/thread-sort";
 export { deriveLocalBranchNameFromRemoteRef, sanitizeNewRefName } from "@t3tools/shared/git";
 
@@ -257,9 +258,12 @@ export function resolveBranchSelectionTarget(input: {
   const { activeProjectCwd, activeWorktreePath, refName } = input;
 
   if (refName.worktreePath) {
+    // A project in a repository subdirectory sits inside its checkout's root.
+    const isProjectCheckout =
+      workspaceRelativeFilePath(activeProjectCwd, refName.worktreePath) !== null;
     return {
       checkoutCwd: refName.worktreePath,
-      nextWorktreePath: refName.worktreePath === activeProjectCwd ? null : refName.worktreePath,
+      nextWorktreePath: isProjectCheckout ? null : refName.worktreePath,
       reuseExistingWorktree: true,
     };
   }