test: reap native app-server fixtures after each test

src/__tests__/acp-test-utils.test.ts

@@ -1,5 +1,5 @@
 import {describe, expect, it} from "vitest";
-import {createObjectDump} from "./acp-test-utils";
+import {createTestFixture, createObjectDump} from "./acp-test-utils";
 
 describe("createObjectDump anonymizer", () => {
     it("anonymizes both direct keys and dotted paths", () => {
@@ -33,3 +33,16 @@ describe("createObjectDump anonymizer", () => {
         expect(parsed.items[1].secret).toBe("second-item");
     });
 });
+
+
+describe("native fixture cleanup", () => {
+    let previous: ReturnType<typeof createTestFixture>;
+    it("owns a running app-server for the current test", async () => {
+        previous = createTestFixture();
+        await previous.getCodexAcpAgent().initialize({protocolVersion: 1});
+        expect(previous.getCodexAcpAgent()["getExitCode"]()).toBeNull();
+    });
+    it("does not leave the preceding test app-server alive", () => {
+        expect(previous.getCodexAcpAgent()["getExitCode"]()).not.toBeNull();
+    });
+});

src/__tests__/acp-test-utils.ts

@@ -13,7 +13,7 @@ import fs from "node:fs";
 import os from "node:os";
 import {AgentMode} from "../AgentMode";
 import {DEFAULT_COLLABORATION_MODE} from "../CollaborationModeConfig";
-import {expect, vi} from "vitest";
+import {afterEach, expect, vi} from "vitest";
 import type {Model, ReasoningEffortOption} from "../app-server/v2";
 import {CodexSubagentEventRouter} from "../subagents/CodexSubagentEventRouter";
 import {CodexEventHandler} from "../CodexEventHandler";
@@ -189,6 +189,13 @@ export function createBaseTestFixture(config: ConnectionConfig): TestFixture {
  * Creates a test fixture with a real Codex connection.
  * Use for integration tests that need to interact with the actual Codex binary.
  */
+const nativeFixtureCleanup = new Set<() => Promise<void>>();
+afterEach(async () => {
+    const pending = [...nativeFixtureCleanup];
+    nativeFixtureCleanup.clear();
+    await Promise.all(pending.map(cleanup => cleanup()));
+});
+
 export function createTestFixture(): TestFixture {
     const pathToCodex = path.resolve(process.cwd(), "node_modules", ".bin", process.platform === 'win32' ? "codex.cmd" : "codex");
     if (!fs.existsSync(pathToCodex)) {
@@ -200,6 +207,20 @@ export function createTestFixture(): TestFixture {
         ...process.env,
         CODEX_HOME: codexHome,
     });
+    // Real fixtures previously accumulated app-servers until the worker exited,
+    // starving later initialize requests and making unrelated commands time out.
+    nativeFixtureCleanup.add(async () => {
+        if (codexConnection.process.exitCode !== null || codexConnection.process.signalCode !== null) return;
+        const exited = new Promise<void>(resolve => codexConnection.process.once("exit", () => resolve()));
+        const deadline = setTimeout(() => codexConnection.process.kill("SIGKILL"), 2000);
+        try {
+            codexConnection.process.stdin.end();
+            await exited;
+        } finally {
+            clearTimeout(deadline);
+            codexConnection.connection.dispose();
+        }
+    });
     codexConnection.process.on("exit", () => {
         removeDirectoryWithRetry(codexHome);
     });