fix(engine): trim attempt-id slug after truncation

packages/loopover-engine/src/miner/worktree-plan.ts

@@ -36,13 +36,18 @@ const MAX_SLUG_LENGTH = 64;
 
 /** Deterministically slugify an attempt id into a filesystem- and git-ref-safe token (same id → same slug). */
 function slugifyAttemptId(attemptId: string): string {
+  // Trim leading/trailing `-`/`.` both before and after truncation (#7528): `.` is allowed mid-slug, so a
+  // pre-trim-only pass misses the case where slice(0, MAX) lands on a literal `.`/`-` and leaves a
+  // git-ref-invalid trailing separator (git check-ref-format rejects refs ending in `.`).
   const slug = attemptId
     .trim()
     .toLowerCase()
     .replace(/[^a-z0-9._-]+/g, "-")
+    .replace(/^[-.]+|[-.]+$/g, "")
+    .slice(0, MAX_SLUG_LENGTH)
     .replace(/^[-.]+|[-.]+$/g, "");
   if (!slug) throw new Error("invalid_attempt_id");
-  return slug.slice(0, MAX_SLUG_LENGTH);
+  return slug;
 }
 
 /**

test/unit/worktree-plan.test.ts

@@ -38,8 +38,32 @@ describe("planWorktree (#4269)", () => {
     expect(long.branchName).toBe(`${WORKTREE_BRANCH_PREFIX}${"x".repeat(64)}`);
   });
 
+  it("strips a trailing '.' produced by truncating at a mid-slug dot (#7528)", () => {
+    // 63 safe chars + '.' + more content past the cap → pre-trim keeps the dot (not at the edge),
+    // slice(0, 64) ends in '.', and the post-truncation trim must remove it for git ref-format.
+    const attemptId = `${"a".repeat(63)}.${"b".repeat(10)}`;
+    const plan = planWorktree({ repoPath: "/repo", attemptId });
+    expect(plan.branchName).toBe(`${WORKTREE_BRANCH_PREFIX}${"a".repeat(63)}`);
+    expect(plan.branchName.endsWith(".")).toBe(false);
+    expect(plan.branchName.endsWith("-")).toBe(false);
+  });
+
+  it("strips a trailing '-' produced by truncating at a mid-slug hyphen (#7528)", () => {
+    const attemptId = `${"a".repeat(63)}-${"b".repeat(10)}`;
+    const plan = planWorktree({ repoPath: "/repo", attemptId });
+    expect(plan.branchName).toBe(`${WORKTREE_BRANCH_PREFIX}${"a".repeat(63)}`);
+    expect(plan.branchName.endsWith("-")).toBe(false);
+  });
+
+  it("leaves a clean truncation boundary untouched when the 64th char is not a separator (#7528)", () => {
+    const attemptId = `${"a".repeat(64)}${"b".repeat(10)}`;
+    const plan = planWorktree({ repoPath: "/repo", attemptId });
+    expect(plan.branchName).toBe(`${WORKTREE_BRANCH_PREFIX}${"a".repeat(64)}`);
+  });
+
   it("rejects an attempt id that sanitizes to nothing", () => {
     expect(() => planWorktree({ repoPath: "/repo", attemptId: "  ---  " })).toThrow(/invalid_attempt_id/);
+    expect(() => planWorktree({ repoPath: "/repo", attemptId: "..." })).toThrow(/invalid_attempt_id/);
   });
 });