test: cut slow suite runtimes and isolate experimental flag from host env

apps/kimi-code/test/cli/goal-prompt.test.ts

@@ -168,6 +168,11 @@ describe('runPrompt headless goal mode', () => {
   let savedExitCode: typeof process.exitCode;
 
   beforeEach(() => {
+    // Pin the experimental engine flag off so runPrompt stays on the v1 path
+    // this suite mocks, regardless of the host environment (matches
+    // run-prompt.test.ts). With the flag on, runPrompt dispatches to the
+    // native v2 runner, which ignores these mocks and hangs the test.
+    vi.stubEnv('KIMI_CODE_EXPERIMENTAL_FLAG', '');
     savedExitCode = process.exitCode;
     mocks.experimentalFeatures = [{ id: 'micro_compaction', enabled: true }];
     mocks.sessions = [];
@@ -180,6 +185,7 @@ describe('runPrompt headless goal mode', () => {
   });
 
   afterEach(() => {
+    vi.unstubAllEnvs();
     process.exitCode = savedExitCode;
   });
 

apps/kimi-code/test/cli/update/preflight.test.ts

@@ -227,6 +227,10 @@ async function flushBackgroundInstall(): Promise<void> {
 
 describe('runUpdatePreflight', () => {
   beforeEach(() => {
+    // Pin the experimental flag off so rollout gating is deterministic
+    // regardless of the host environment (the flag bypasses batch holds).
+    // Tests that exercise the bypass opt back in with `vi.stubEnv(..., '1')`.
+    vi.stubEnv('KIMI_CODE_EXPERIMENTAL_FLAG', '');
     mocks.readUpdateInstallState.mockResolvedValue(emptyUpdateInstallState());
     mocks.writeUpdateInstallState.mockResolvedValue(undefined);
     mocks.loadTuiConfig.mockResolvedValue(tuiConfig());

packages/agent-core-v2/src/session/sessionFs/fsWatchService.ts

@@ -30,8 +30,16 @@ import type { FsChangeEntry, FsChangeEvent } from '@moonshot-ai/protocol';
 
 import { ISessionFsWatchService } from './fsWatch';
 
-const DEBOUNCE_MS = 200;
-const MAX_CHANGES_PER_WINDOW = 500;
+const DEFAULT_DEBOUNCE_MS = 200;
+const DEFAULT_MAX_CHANGES_PER_WINDOW = 500;
+
+/** Positive-int env read for the test-only window overrides below. */
+function readPositiveIntEnv(name: string, fallback: number): number {
+  const raw = process.env[name];
+  if (raw === undefined || raw === '') return fallback;
+  const n = Number.parseInt(raw, 10);
+  return Number.isFinite(n) && n > 0 ? n : fallback;
+}
 
 export class SessionFsWatchService extends Disposable implements ISessionFsWatchService {
   declare readonly _serviceBrand: undefined;
@@ -48,6 +56,18 @@ export class SessionFsWatchService extends Disposable implements ISessionFsWatch
   private rawCount = 0;
   private truncated = false;
 
+  // Env-overridable for tests: the burst-truncation e2e cannot rely on
+  // chokidar delivering >500 events inside one 200ms window under CPU
+  // contention. Production leaves both unset and gets the defaults.
+  private readonly debounceMs = readPositiveIntEnv(
+    'KIMI_CODE_FS_WATCH_DEBOUNCE_MS',
+    DEFAULT_DEBOUNCE_MS,
+  );
+  private readonly maxChangesPerWindow = readPositiveIntEnv(
+    'KIMI_CODE_FS_WATCH_MAX_CHANGES_PER_WINDOW',
+    DEFAULT_MAX_CHANGES_PER_WINDOW,
+  );
+
   /** Always present; starts with `.git/` and is augmented with `.gitignore` once loaded. */
   private readonly matcher: Ignore = ignore().add('.git/');
   private gitignoreLoaded = false;
@@ -116,12 +136,12 @@ export class SessionFsWatchService extends Disposable implements ISessionFsWatch
 
     this.pending.push({ path: rel, change: e.action, kind: e.kind });
     this.rawCount += 1;
-    if (this.pending.length > MAX_CHANGES_PER_WINDOW) {
+    if (this.pending.length > this.maxChangesPerWindow) {
       this.truncated = true;
       this.pending = [];
     }
     if (this.debounceTimer === undefined) {
-      const timer = setTimeout(() => this.flush(), DEBOUNCE_MS);
+      const timer = setTimeout(() => this.flush(), this.debounceMs);
       timer.unref?.();
       this.debounceTimer = timer;
     }
@@ -139,7 +159,7 @@ export class SessionFsWatchService extends Disposable implements ISessionFsWatch
 
     const event: FsChangeEvent = {
       changes,
-      coalesced_window_ms: DEBOUNCE_MS,
+      coalesced_window_ms: this.debounceMs,
       ...(truncated ? { truncated: true, count } : {}),
     };
     this.emitter.fire(event);

packages/agent-core-v2/test/agent/externalHooks/runner.test.ts

@@ -85,7 +85,7 @@ describe('runHook process runner', () => {
       hostProcess,
       nodeCommand('setTimeout(() => {}, 10000);'),
       { tool_name: 'Bash' },
-      { timeout: 1 },
+      { timeout: 0.05 },
     );
 
     expect(result.action).toBe('allow');