fix(gateway): enforce singleton lock

src/infra/gateway-lock.test.ts

@@ -0,0 +1,55 @@
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+
+import { describe, expect, it } from "vitest";
+
+import { acquireGatewayLock, GatewayLockError } from "./gateway-lock.js";
+
+async function makeEnv() {
+  const dir = await fs.mkdtemp(path.join(os.tmpdir(), "clawdbot-gateway-lock-"));
+  const configPath = path.join(dir, "clawdbot.json");
+  await fs.writeFile(configPath, "{}", "utf8");
+  return {
+    env: {
+      ...process.env,
+      CLAWDBOT_STATE_DIR: dir,
+      CLAWDBOT_CONFIG_PATH: configPath,
+    },
+    cleanup: async () => {
+      await fs.rm(dir, { recursive: true, force: true });
+    },
+  };
+}
+
+describe("gateway lock", () => {
+  it("blocks concurrent acquisition until release", async () => {
+    const { env, cleanup } = await makeEnv();
+    const lock = await acquireGatewayLock({
+      env,
+      allowInTests: true,
+      timeoutMs: 200,
+      pollIntervalMs: 20,
+    });
+    expect(lock).not.toBeNull();
+
+    await expect(
+      acquireGatewayLock({
+        env,
+        allowInTests: true,
+        timeoutMs: 200,
+        pollIntervalMs: 20,
+      }),
+    ).rejects.toBeInstanceOf(GatewayLockError);
+
+    await lock?.release();
+    const lock2 = await acquireGatewayLock({
+      env,
+      allowInTests: true,
+      timeoutMs: 200,
+      pollIntervalMs: 20,
+    });
+    await lock2?.release();
+    await cleanup();
+  });
+});