Address review feedback (round 2)

- Add `--` separator to git fetch in fetchRef so a ref beginning with
  `-` can't be parsed as an option, matching remoteBranchExists.
- Add a fetch-failure test for createWorktreeForRemoteBranch.
- Drop the redundant onClick on the dialog Cancel button; onOpenChange
  already drives cancel, mirroring BranchMismatchDialog.

Author: haacked

packages/git/src/queries.ts

@@ -1073,7 +1073,8 @@ export async function fetchRef(
   ref: string,
 ): Promise<boolean> {
   try {
-    await git.raw(["fetch", "--quiet", "--no-tags", remote, ref]);
+    // `--` keeps a ref beginning with `-` from being parsed as an option.
+    await git.raw(["fetch", "--quiet", "--no-tags", remote, "--", ref]);
     return true;
   } catch {
     return false;

packages/git/src/worktree.test.ts

@@ -285,4 +285,22 @@ describe("WorktreeManager.createWorktreeForRemoteBranch", () => {
     ).trim();
     expect(upstream).toBe("origin/contributor/pr");
   });
+
+  it("rejects when the remote branch cannot be fetched", async () => {
+    // Point origin at a path that does not exist so the fetch fails.
+    await createGitClient(localDir).remote([
+      "set-url",
+      "origin",
+      "/nonexistent/path/to/remote",
+    ]);
+
+    const manager = new WorktreeManager({
+      mainRepoPath: localDir,
+      worktreeBasePath: worktreeBaseDir,
+    });
+
+    await expect(
+      manager.createWorktreeForRemoteBranch("contributor/pr"),
+    ).rejects.toThrow(/Failed to fetch branch 'contributor\/pr'/);
+  });
 });

packages/ui/src/features/task-detail/components/RemoteBranchCheckoutDialog.tsx

@@ -35,7 +35,7 @@ export function RemoteBranchCheckoutDialog() {
 
         <Flex justify="end" gap="2" mt="4">
           <AlertDialog.Cancel>
-            <Button variant="soft" color="gray" size="1" onClick={cancel}>
+            <Button variant="soft" color="gray" size="1">
               Cancel
             </Button>
           </AlertDialog.Cancel>