test/py: add test of basic shell functionality

This tests whether the following features of the U-Boot shell:
- Execution of a directly entered command.
- Compound commands (; delimiter).
- Quoting of arguments containing spaces.
- Executing commands from environment variables.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>

test/py/tests/test_shell_basics.py

@@ -0,0 +1,42 @@
+# Copyright (c) 2015-2016, NVIDIA CORPORATION. All rights reserved.
+#
+# SPDX-License-Identifier: GPL-2.0
+
+# Test basic shell functionality, such as commands separate by semi-colons.
+
+def test_shell_execute(u_boot_console):
+    '''Test any shell command.'''
+
+    response = u_boot_console.run_command('echo hello')
+    assert response.strip() == 'hello'
+
+def test_shell_semicolon_two(u_boot_console):
+    '''Test two shell commands separate by a semi-colon.'''
+
+    cmd = 'echo hello; echo world'
+    response = u_boot_console.run_command(cmd)
+    # This validation method ignores the exact whitespace between the strings
+    assert response.index('hello') < response.index('world')
+
+def test_shell_semicolon_three(u_boot_console):
+    '''Test three shell commands separate by a semi-colon, with variable
+    expansion dependencies between them.'''
+
+    cmd = 'setenv list 1; setenv list ${list}2; setenv list ${list}3; ' + \
+        'echo ${list}'
+    response = u_boot_console.run_command(cmd)
+    assert response.strip() == '123'
+    u_boot_console.run_command('setenv list')
+
+def test_shell_run(u_boot_console):
+    '''Test the "run" shell command.'''
+
+    u_boot_console.run_command('setenv foo \"setenv monty 1; setenv python 2\"')
+    u_boot_console.run_command('run foo')
+    response = u_boot_console.run_command('echo $monty')
+    assert response.strip() == '1'
+    response = u_boot_console.run_command('echo $python')
+    assert response.strip() == '2'
+    u_boot_console.run_command('setenv foo')
+    u_boot_console.run_command('setenv monty')
+    u_boot_console.run_command('setenv python')