ci: cap extension shard vitest workers

test/vitest-projects-config.test.ts

@@ -12,7 +12,10 @@ import {
 } from "./vitest/vitest.contracts-shared.ts";
 import { createGatewayVitestConfig } from "./vitest/vitest.gateway.config.ts";
 import { createPluginSdkLightVitestConfig } from "./vitest/vitest.plugin-sdk-light.config.ts";
-import { sharedVitestConfig } from "./vitest/vitest.shared.config.ts";
+import {
+  resolveSharedVitestWorkerConfig,
+  sharedVitestConfig,
+} from "./vitest/vitest.shared.config.ts";
 import { createUiVitestConfig } from "./vitest/vitest.ui.config.ts";
 import { createUnitFastVitestConfig } from "./vitest/vitest.unit-fast.config.ts";
 import unitUiConfig from "./vitest/vitest.unit-ui.config.ts";
@@ -44,6 +47,39 @@ describe("projects vitest config", () => {
     expect(createContractsVitestConfig(pluginContractPatterns).test.pool).toBe("forks");
   });
 
+  it("honors explicit worker caps in CI vitest lanes", () => {
+    expect(
+      resolveSharedVitestWorkerConfig({
+        env: { CI: "true", OPENCLAW_VITEST_MAX_WORKERS: "1" },
+        isCI: true,
+        isWindows: false,
+        localScheduling: {
+          fileParallelism: false,
+          maxWorkers: 1,
+          throttledBySystem: false,
+        },
+      }),
+    ).toEqual({
+      fileParallelism: false,
+      maxWorkers: 1,
+    });
+    expect(
+      resolveSharedVitestWorkerConfig({
+        env: { CI: "true" },
+        isCI: true,
+        isWindows: false,
+        localScheduling: {
+          fileParallelism: false,
+          maxWorkers: 1,
+          throttledBySystem: false,
+        },
+      }),
+    ).toEqual({
+      fileParallelism: true,
+      maxWorkers: 3,
+    });
+  });
+
   it("keeps contract shards on the non-isolated fork runner by default", () => {
     const config = createContractsVitestConfig(pluginContractPatterns);
     expect(config.test.pool).toBe("forks");

test/vitest/vitest.shared.config.ts

@@ -76,7 +76,43 @@ const localScheduling = resolveLocalVitestScheduling(
   detectVitestHostInfo(),
   defaultPool,
 );
-const ciWorkers = isWindows ? 2 : 3;
+
+function hasWorkerOverride(env: Record<string, string | undefined>): boolean {
+  return Boolean((env.OPENCLAW_VITEST_MAX_WORKERS ?? env.OPENCLAW_TEST_WORKERS)?.trim());
+}
+
+export function resolveSharedVitestWorkerConfig(params: {
+  env?: Record<string, string | undefined>;
+  isCI?: boolean;
+  isWindows?: boolean;
+  localScheduling?: LocalVitestScheduling;
+}): Pick<LocalVitestScheduling, "fileParallelism" | "maxWorkers"> {
+  const env = params.env ?? process.env;
+  const local = params.localScheduling ?? localScheduling;
+  if (hasWorkerOverride(env)) {
+    return {
+      fileParallelism: local.fileParallelism,
+      maxWorkers: local.maxWorkers,
+    };
+  }
+  if (params.isCI ?? isCI) {
+    return {
+      fileParallelism: true,
+      maxWorkers: (params.isWindows ?? isWindows) ? 2 : 3,
+    };
+  }
+  return {
+    fileParallelism: local.fileParallelism,
+    maxWorkers: local.maxWorkers,
+  };
+}
+
+const workerConfig = resolveSharedVitestWorkerConfig({
+  env: process.env,
+  isCI,
+  isWindows,
+  localScheduling,
+});
 
 if (!isCI && localScheduling.throttledBySystem && shouldPrintVitestThrottle(process.env)) {
   console.error(
@@ -118,8 +154,8 @@ export const sharedVitestConfig = {
     isolate: false,
     pool: defaultPool,
     runner: nonIsolatedRunnerPath,
-    maxWorkers: isCI ? ciWorkers : localScheduling.maxWorkers,
-    fileParallelism: isCI ? true : localScheduling.fileParallelism,
+    maxWorkers: workerConfig.maxWorkers,
+    fileParallelism: workerConfig.fileParallelism,
     forceRerunTriggers: [
       "package.json",
       "pnpm-lock.yaml",