test(vm): add e2e integration tests for gateway binary

Two #[ignore] tests that require libkrun + pre-built rootfs:
- gateway_boots_and_service_becomes_reachable: starts the full gateway
  and verifies the gRPC service on port 30051
- gateway_exec_runs_guest_command: runs /bin/true inside the VM via
  --exec and checks the exit code

Author: drew

crates/navigator-vm/tests/gateway_integration.rs

@@ -0,0 +1,132 @@
+// SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+//! Integration tests for the standalone `gateway` binary.
+//!
+//! These tests require:
+//! - libkrun installed (e.g. `brew tap slp/krun && brew install libkrun`)
+//! - macOS ARM64 with Apple Hypervisor.framework
+//! - A pre-built rootfs at `~/.local/share/nemoclaw/gateway/rootfs`
+//!
+//! All tests are `#[ignore]` — run them explicitly:
+//!
+//! ```sh
+//! cargo test -p navigator-vm --test gateway_integration -- --ignored
+//! ```
+
+#![allow(unsafe_code)]
+
+use std::net::{SocketAddr, TcpStream};
+use std::process::{Command, Stdio};
+use std::time::{Duration, Instant};
+
+/// Path to the built `gateway` binary (resolved by Cargo at compile time).
+const GATEWAY: &str = env!("CARGO_BIN_EXE_gateway");
+
+// ── Helpers ────────────────────────────────────────────────────────────
+
+/// Codesign the binary on macOS so it can access Hypervisor.framework.
+fn codesign_if_needed() {
+    if cfg!(target_os = "macos") {
+        let entitlements = format!("{}/entitlements.plist", env!("CARGO_MANIFEST_DIR"));
+        let status = Command::new("codesign")
+            .args([
+                "--entitlements",
+                &entitlements,
+                "--force",
+                "-s",
+                "-",
+                GATEWAY,
+            ])
+            .status()
+            .expect("codesign command failed to execute");
+        assert!(status.success(), "failed to codesign gateway binary");
+    }
+}
+
+/// Build environment variables so libkrun can find libkrunfw at runtime.
+fn libkrun_env() -> Vec<(&'static str, String)> {
+    if cfg!(target_os = "macos") {
+        let homebrew_lib = Command::new("brew")
+            .args(["--prefix"])
+            .output()
+            .ok()
+            .and_then(|o| String::from_utf8(o.stdout).ok())
+            .map(|s| format!("{}/lib", s.trim()))
+            .unwrap_or_else(|| "/opt/homebrew/lib".to_string());
+
+        let existing = std::env::var("DYLD_FALLBACK_LIBRARY_PATH").unwrap_or_default();
+        let val = if existing.is_empty() {
+            homebrew_lib
+        } else {
+            format!("{homebrew_lib}:{existing}")
+        };
+        vec![("DYLD_FALLBACK_LIBRARY_PATH", val)]
+    } else {
+        vec![]
+    }
+}
+
+// ── Tests ──────────────────────────────────────────────────────────────
+
+/// Boot the full NemoClaw gateway and verify the gRPC service becomes
+/// reachable on port 30051.
+#[test]
+#[ignore] // requires libkrun + rootfs
+fn gateway_boots_and_service_becomes_reachable() {
+    codesign_if_needed();
+
+    let mut cmd = Command::new(GATEWAY);
+    cmd.stdout(Stdio::null()).stderr(Stdio::piped());
+    for (k, v) in libkrun_env() {
+        cmd.env(k, v);
+    }
+
+    let mut child = cmd.spawn().expect("failed to start gateway");
+
+    // Poll for the navigator gRPC service.
+    let addr: SocketAddr = ([127, 0, 0, 1], 30051).into();
+    let timeout = Duration::from_secs(180);
+    let start = Instant::now();
+    let mut reachable = false;
+
+    while start.elapsed() < timeout {
+        if TcpStream::connect_timeout(&addr, Duration::from_secs(1)).is_ok() {
+            reachable = true;
+            break;
+        }
+        std::thread::sleep(Duration::from_secs(2));
+    }
+
+    // Tear down regardless of result.
+    let _ = unsafe { libc::kill(child.id() as i32, libc::SIGTERM) };
+    let _ = child.wait();
+
+    assert!(
+        reachable,
+        "gateway service on port 30051 not reachable within {timeout:?}"
+    );
+}
+
+/// Run a trivial command inside the VM via `--exec` and verify it exits
+/// successfully, proving the VM boots and can execute guest processes.
+#[test]
+#[ignore] // requires libkrun + rootfs
+fn gateway_exec_runs_guest_command() {
+    codesign_if_needed();
+
+    let mut cmd = Command::new(GATEWAY);
+    cmd.args(["--exec", "/bin/true"]);
+    for (k, v) in libkrun_env() {
+        cmd.env(k, v);
+    }
+
+    let output = cmd.output().expect("failed to run gateway --exec");
+
+    assert!(
+        output.status.success(),
+        "gateway --exec /bin/true failed with status {:?}\nstderr: {}",
+        output.status,
+        String::from_utf8_lossy(&output.stderr),
+    );
+}