fix(test): hard kill boundary prep timeouts

scripts/prepare-extension-package-boundary-artifacts.mjs

@@ -195,10 +195,11 @@ function abortSiblingSteps(abortController) {
   }
 }
 
-function runNodeStep(label, args, timeoutMs, params = {}) {
+export function runNodeStep(label, args, timeoutMs, params = {}) {
   const abortController = params.abortController;
+  const spawnImpl = params.spawnImpl ?? spawn;
   return new Promise((resolvePromise, rejectPromise) => {
-    const child = spawn(process.execPath, args, {
+    const child = spawnImpl(process.execPath, args, {
       cwd: repoRoot,
       env: params.env ? { ...process.env, ...params.env } : process.env,
       signal: abortController?.signal,
@@ -212,8 +213,8 @@ function runNodeStep(label, args, timeoutMs, params = {}) {
       if (settled) {
         return;
       }
-      child.kill("SIGTERM");
       settled = true;
+      child.kill("SIGKILL");
       stdoutWriter.flush();
       stderrWriter.flush();
       abortSiblingSteps(abortController);

test/scripts/prepare-extension-package-boundary-artifacts.test.ts

@@ -1,3 +1,4 @@
+import { EventEmitter } from "node:events";
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
@@ -6,12 +7,21 @@ import {
   createPrefixedOutputWriter,
   isArtifactSetFresh,
   parseMode,
+  runNodeStep,
   runNodeSteps,
   runNodeStepsInParallel,
 } from "../../scripts/prepare-extension-package-boundary-artifacts.mjs";
 
 const tempRoots = new Set<string>();
 
+function createMockPipe() {
+  const pipe = new EventEmitter() as EventEmitter & {
+    setEncoding: (encoding: string) => void;
+  };
+  pipe.setEncoding = () => {};
+  return pipe;
+}
+
 afterEach(() => {
   for (const rootDir of tempRoots) {
     fs.rmSync(rootDir, { force: true, recursive: true });
@@ -58,6 +68,33 @@ describe("prepare-extension-package-boundary-artifacts", () => {
     expect(Date.now() - startedAt).toBeLessThan(abortBudgetMs);
   }, 45_000);
 
+  it("hard-kills timed out prep steps", async () => {
+    const signals: Array<NodeJS.Signals | number | undefined> = [];
+    const child = new EventEmitter() as EventEmitter & {
+      kill: (signal?: NodeJS.Signals | number) => boolean;
+      stderr: ReturnType<typeof createMockPipe>;
+      stdout: ReturnType<typeof createMockPipe>;
+    };
+    child.stdout = createMockPipe();
+    child.stderr = createMockPipe();
+    child.kill = (signal) => {
+      signals.push(signal);
+      return true;
+    };
+
+    await expect(
+      runNodeStep("hung-prep", ["--eval", "setTimeout(() => {}, 60_000)"], 5, {
+        spawnImpl(command: string, args: string[]) {
+          expect(command).toBe(process.execPath);
+          expect(args).toEqual(["--eval", "setTimeout(() => {}, 60_000)"]);
+          return child;
+        },
+      }),
+    ).rejects.toThrow("hung-prep timed out after 5ms");
+
+    expect(signals).toEqual(["SIGKILL"]);
+  });
+
   it("runs boundary prep steps serially for local checks", async () => {
     const rootDir = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-boundary-serial-"));
     tempRoots.add(rootDir);