test(agent): red test for single merged grok residual with ceremony lines

Author: TheGreatAxios

src/agent/grok-residual.test.ts

@@ -0,0 +1,58 @@
+import { describe, expect, it } from "bun:test";
+import { promptResidual } from "./model-family-policy.js";
+import {
+  buildGrokLeafAntiThrashNote,
+  buildSubAgentSystemPrompt,
+} from "./prompts.js";
+
+// The three Grok ceremony lines (CL-7768 Design, merged by CL-8296): no git,
+// no pre-plan, verify once.
+const CEREMONY_LINES = [
+  "- Never run git add, git commit, git stash, or any other state-changing git command unless the user asks.",
+  "- Do not narrate a plan before acting on a small task; act, then report.",
+  "- Verify with the test command once at the end, not after every edit.",
+] as const;
+
+function countOccurrences(haystack: string, needle: string): number {
+  return haystack.split(needle).length - 1;
+}
+
+describe("grok ceremony merge (CL-8296)", () => {
+  it("exposes a single grok residual with each ceremony line exactly once", () => {
+    const residual = promptResidual("grok");
+    expect(residual).toContain("Finish bias (xAI / Grok worker):");
+    for (const line of CEREMONY_LINES) {
+      expect(countOccurrences(residual, line)).toBe(1);
+    }
+  });
+
+  it("keeps the don't re-read line exactly once — no duplicate", () => {
+    const residual = promptResidual("grok");
+    expect(countOccurrences(residual, "re-open paths you already read")).toBe(
+      1,
+    );
+  });
+
+  it("is grok-only: every other family resolves to an empty residual", () => {
+    expect(promptResidual("default")).toBe("");
+    expect(promptResidual("kimi")).toBe("");
+    expect(promptResidual("muse")).toBe("");
+  });
+
+  it("buildGrokLeafAntiThrashNote is the same single residual (one source of truth)", () => {
+    expect(buildGrokLeafAntiThrashNote()).toBe(promptResidual("grok"));
+  });
+
+  it("the assembled grok worker prompt carries the merged residual exactly once", () => {
+    const prompt = buildSubAgentSystemPrompt(undefined, undefined, undefined, {
+      orchestrator: false,
+      grokAntiThrash: true,
+    });
+    expect(
+      countOccurrences(prompt, "Finish bias (xAI / Grok worker):"),
+    ).toBe(1);
+    for (const line of CEREMONY_LINES) {
+      expect(countOccurrences(prompt, line)).toBe(1);
+    }
+  });
+});