[Android] Fix environment variable handling in devil_env.

build/android/devil/devil_env_test.py

Index: build/android/devil/devil_env_test.py
diff --git a/build/android/devil/devil_env_test.py b/build/android/devil/devil_env_test.py
new file mode 100755
index 0000000000000000000000000000000000000000..5bfef6687397c491b54396e6bdbc84f8b92da23e
--- /dev/null
+++ b/build/android/devil/devil_env_test.py
@@ -0,0 +1,62 @@
+#!/usr/bin/env python
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# pylint: disable=protected-access
+
+import logging
+import sys
+import unittest
+
+from devil import devil_env
+
+_sys_path_before = list(sys.path)
+with devil_env.SysPath(devil_env.config.LocalPath('pymock')):
+  _sys_path_with_pymock = list(sys.path)
+  import mock # pylint: disable=import-error
+_sys_path_after = list(sys.path)
+
+class DevilEnvTest(unittest.TestCase):
+
+  def testSysPath(self):
+    self.assertEquals(_sys_path_before, _sys_path_after)
+    self.assertEquals(
+        _sys_path_before + [devil_env.config.LocalPath('pymock')],
+        _sys_path_with_pymock)

[mikecase (-- gone --), 2015/12/08 03:44:27]

I think its kinda weird that you are testing being able to import pymock when
pretty much nothing is going to work at all if the import fails.

Like, won't you just get an import errors in the "import mock" line before this
test ever runs.

I guess the assert euqals _sys_path_before, _sys_path_after part is a useful
test.

[jbudorick, 2015/12/08 03:48:17]

this isn't testing the import of pymock specifically; it's testing the path
manipulation that SysPath does.
not necessarily; this is also validating the order.
yep

+
+  def testGetEnvironmentVariableConfig_configType(self):
+    with mock.patch('os.environ.get',
+                    mock.Mock(side_effect=lambda _env_var: None)):
+      env_config = devil_env._GetEnvironmentVariableConfig()
+    self.assertEquals('BaseConfig', env_config.get('config_type'))
+
+  def testGetEnvironmentVariableConfig_noEnv(self):
+    with mock.patch('os.environ.get',
+                    mock.Mock(side_effect=lambda _env_var: None)):
+      env_config = devil_env._GetEnvironmentVariableConfig()
+    self.assertEquals({}, env_config.get('dependencies'))
+
+  def testGetEnvironmentVariableConfig_adbPath(self):
+    def mock_environment(env_var):
+      return '/my/fake/adb/path' if env_var == 'ADB_PATH' else None
+
+    with mock.patch('os.environ.get',
+                    mock.Mock(side_effect=mock_environment)):
+      env_config = devil_env._GetEnvironmentVariableConfig()
+    self.assertEquals(
+        {
+          'adb': {
+            'file_info': {
+              'android_linux2': {

[mikecase (-- gone --), 2015/12/08 03:44:27]

where is "android_linux2" coming from?

[jbudorick, 2015/12/08 03:48:17]

see other file

+                'local_paths': ['/my/fake/adb/path'],
+              },
+            },
+          },
+        },
+        env_config.get('dependencies'))
+
+
+if __name__ == '__main__':
+  logging.getLogger().setLevel(logging.DEBUG)
+  unittest.main(verbosity=2)