vpl: Test that VPL runs correctly through to U-Boot proper

Check the TPL -> VPL -> SPL -> U-Boot path by running the 'help' command
in U-Boot.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/py/tests/test_help.py b/test/py/tests/test_help.py
index d50295e..bac0a29 100644
--- a/test/py/tests/test_help.py
+++ b/test/py/tests/test_help.py
@@ -2,7 +2,21 @@
 # Copyright (c) 2015 Stephen Warren
 # Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
 
+import pytest
+
 def test_help(u_boot_console):
     """Test that the "help" command can be executed."""
 
     u_boot_console.run_command('help')
+
+@pytest.mark.boardspec('sandbox_vpl')
+def test_vpl_help(u_boot_console):
+    try:
+        cons = u_boot_console
+        cons.restart_uboot()
+        cons.run_command('help')
+        output = cons.get_spawn_output().replace('\r', '')
+        assert 'print command description/usage' in output
+    finally:
+        # Restart afterward to get the normal device tree back
+        u_boot_console.restart_uboot()