fix: harden onboarding for non-systemd environments

src/daemon/systemd-availability.test.ts

@@ -0,0 +1,35 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const execFileMock = vi.hoisted(() => vi.fn());
+
+vi.mock("node:child_process", () => ({
+  execFile: execFileMock,
+}));
+
+import { isSystemdUserServiceAvailable } from "./systemd.js";
+
+describe("systemd availability", () => {
+  beforeEach(() => {
+    execFileMock.mockReset();
+  });
+
+  it("returns true when systemctl --user succeeds", async () => {
+    execFileMock.mockImplementation((_cmd, _args, _opts, cb) => {
+      cb(null, "", "");
+    });
+    await expect(isSystemdUserServiceAvailable()).resolves.toBe(true);
+  });
+
+  it("returns false when systemd user bus is unavailable", async () => {
+    execFileMock.mockImplementation((_cmd, _args, _opts, cb) => {
+      const err = new Error("Failed to connect to bus") as Error & {
+        stderr?: string;
+        code?: number;
+      };
+      err.stderr = "Failed to connect to bus";
+      err.code = 1;
+      cb(err, "", "");
+    });
+    await expect(isSystemdUserServiceAvailable()).resolves.toBe(false);
+  });
+});

src/daemon/systemd.ts

@@ -337,6 +337,19 @@ async function execSystemctl(
   }
 }
 
+export async function isSystemdUserServiceAvailable(): Promise<boolean> {
+  const res = await execSystemctl(["--user", "status"]);
+  if (res.code === 0) return true;
+  const detail = `${res.stderr} ${res.stdout}`.toLowerCase();
+  if (!detail) return false;
+  if (detail.includes("not found")) return false;
+  if (detail.includes("failed to connect")) return false;
+  if (detail.includes("not been booted")) return false;
+  if (detail.includes("no such file or directory")) return false;
+  if (detail.includes("not supported")) return false;
+  return false;
+}
+
 async function assertSystemdAvailable() {
   const res = await execSystemctl(["--user", "status"]);
   if (res.code === 0) return;