test(plugins): avoid subprocess in legacy plugin-sdk import test

src/infra/heartbeat-runner.returns-default-unset.test.ts

@@ -1018,6 +1018,7 @@ describe("runHeartbeatOnce", () => {
     reason?: "interval" | "wake";
     queueCronEvent?: boolean;
     replyText?: string;
+    cfgOverrides?: Partial<OpenClawConfig>;
   }) {
     const tmpDir = await createCaseDir("openclaw-hb");
     const storePath = path.join(tmpDir, "sessions.json");
@@ -1041,7 +1042,7 @@ describe("runHeartbeatOnce", () => {
       await fs.mkdir(path.join(workspaceDir, "HEARTBEAT.md"), { recursive: true });
     }
 
-    const cfg: OpenClawConfig = {
+    const cfgBase: OpenClawConfig = {
       agents: {
         defaults: {
           workspace: workspaceDir,
@@ -1051,6 +1052,9 @@ describe("runHeartbeatOnce", () => {
       channels: { whatsapp: { allowFrom: ["*"] } },
       session: { store: storePath },
     };
+    const cfg: OpenClawConfig = params.cfgOverrides
+      ? { ...cfgBase, ...params.cfgOverrides }
+      : cfgBase;
     const sessionKey = resolveMainSessionKey(cfg);
     await fs.writeFile(
       storePath,
@@ -1083,7 +1087,7 @@ describe("runHeartbeatOnce", () => {
     return { res, replySpy, sendWhatsApp, workspaceDir };
   }
 
-  it("adds explicit workspace HEARTBEAT.md path guidance to heartbeat prompts", async () => {
+  it("adds explicit workspace HEARTBEAT.md path guidance to default heartbeat prompts", async () => {
     const { res, replySpy, sendWhatsApp, workspaceDir } = await runHeartbeatFileScenario({
       fileState: "actionable",
       reason: "interval",
@@ -1102,6 +1106,35 @@ describe("runHeartbeatOnce", () => {
     }
   });
 
+  it("does not mutate a custom heartbeat prompt", async () => {
+    const customPrompt =
+      "Read HEARTBEAT.md if it exists (workspace context). Use the system prompt only.";
+    const { res, replySpy } = await runHeartbeatFileScenario({
+      fileState: "actionable",
+      reason: "interval",
+      replyText: "Checked logs and PRs",
+      cfgOverrides: {
+        agents: {
+          defaults: {
+            heartbeat: {
+              prompt: customPrompt,
+            },
+          },
+        },
+      },
+    });
+    try {
+      expect(res.status).toBe("ran");
+      expect(replySpy).toHaveBeenCalledTimes(1);
+      const calledCtx = replySpy.mock.calls[0]?.[0] as { Body?: string };
+      expect(calledCtx.Body).toContain(customPrompt);
+      expect(calledCtx.Body).not.toContain("Do not read docs/heartbeat.md.");
+      expect(calledCtx.Body).not.toContain("use workspace file");
+    } finally {
+      replySpy.mockRestore();
+    }
+  });
+
   it("applies HEARTBEAT.md gating rules across file states and triggers", async () => {
     const cases: Array<{
       name: string;

src/infra/heartbeat-runner.ts

@@ -560,7 +560,15 @@ type HeartbeatPromptResolution = {
   hasCronEvents: boolean;
 };
 
-function appendHeartbeatWorkspacePathHint(prompt: string, workspaceDir: string): string {
+function appendHeartbeatWorkspacePathHint(params: {
+  prompt: string;
+  workspaceDir: string;
+  shouldAppend: boolean;
+}): string {
+  const { prompt, workspaceDir, shouldAppend } = params;
+  if (!shouldAppend) {
+    return prompt;
+  }
   if (!/heartbeat\.md/i.test(prompt)) {
     return prompt;
   }
@@ -597,7 +605,20 @@ function resolveHeartbeatRunPrompt(params: {
     : hasCronEvents
       ? buildCronEventPrompt(cronEvents, { deliverToUser: params.canRelayToUser })
       : resolveHeartbeatPrompt(params.cfg, params.heartbeat);
-  const prompt = appendHeartbeatWorkspacePathHint(basePrompt, params.workspaceDir);
+  const configuredPromptRaw =
+    params.heartbeat?.prompt ?? params.cfg.agents?.defaults?.heartbeat?.prompt;
+  const effectivePrompt = resolveHeartbeatPromptText(configuredPromptRaw);
+  const defaultPrompt = resolveHeartbeatPromptText(undefined);
+  const isUsingDefaultPrompt = effectivePrompt === defaultPrompt;
+
+  const prompt = appendHeartbeatWorkspacePathHint({
+    prompt: basePrompt,
+    workspaceDir: params.workspaceDir,
+    // Only append the hint when using the built-in default heartbeat prompt.
+    // If the user configured a custom prompt, do not mutate it.
+    // Also: treat empty-string overrides as a request to fall back to the default.
+    shouldAppend: isUsingDefaultPrompt && !hasExecCompletion && !hasCronEvents,
+  });
 
   return { prompt, hasExecCompletion, hasCronEvents };
 }

src/plugins/loader.test.ts

@@ -1,8 +1,6 @@
-import { execFileSync } from "node:child_process";
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
-import { pathToFileURL } from "node:url";
 import { afterAll, afterEach, describe, expect, it, vi } from "vitest";
 import { withEnv } from "../test-utils/env.js";
 async function importFreshPluginTestModules() {
@@ -1354,37 +1352,25 @@ describe("loadOpenClawPlugins", () => {
 };`,
     });
 
-    const loaderModuleUrl = pathToFileURL(
-      path.join(process.cwd(), "src", "plugins", "loader.ts"),
-    ).href;
-    const script = `
-      import { loadOpenClawPlugins } from ${JSON.stringify(loaderModuleUrl)};
-      const registry = loadOpenClawPlugins({
-        cache: false,
-        workspaceDir: ${JSON.stringify(plugin.dir)},
-        config: {
-          plugins: {
-            load: { paths: [${JSON.stringify(plugin.file)}] },
-            allow: ["legacy-root-import"],
-          },
-        },
-      });
-      const record = registry.plugins.find((entry) => entry.id === "legacy-root-import");
-      if (!record || record.status !== "loaded") {
-        console.error(record?.error ?? "legacy-root-import missing");
-        process.exit(1);
-      }
-    `;
-
-    execFileSync(process.execPath, ["--import", "tsx", "--input-type=module", "-e", script], {
-      cwd: process.cwd(),
-      env: {
-        ...process.env,
+    const registry = withEnv(
+      {
         OPENCLAW_BUNDLED_PLUGINS_DIR: "/nonexistent/bundled/plugins",
       },
-      encoding: "utf-8",
-      stdio: "pipe",
-    });
+      () =>
+        loadOpenClawPlugins({
+          cache: false,
+          workspaceDir: plugin.dir,
+          config: {
+            plugins: {
+              load: { paths: [plugin.file] },
+              allow: ["legacy-root-import"],
+            },
+          },
+        }),
+    );
+
+    const record = registry.plugins.find((entry) => entry.id === "legacy-root-import");
+    expect(record?.status).toBe("loaded");
   });
 
   it("prefers dist plugin-sdk alias when loader runs from dist", () => {