Allow RunShellCommand to work even with very large commands

build/android/pylib/utils/device_temp_file_test.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 """
 Unit tests for the contents of device_temp_file.py.
 """
 
 import logging
 import os
 import sys
 import unittest
 
 from pylib import constants
+from pylib.device import adb_wrapper
+from pylib.device import device_errors
 from pylib.utils import device_temp_file
+from pylib.utils import mock_calls
 
 sys.path.append(os.path.join(
     constants.DIR_SOURCE_ROOT, 'third_party', 'pymock'))
 import mock # pylint: disable=F0401
 
-class DeviceTempFileTest(unittest.TestCase):
+class DeviceTempFileTest(mock_calls.TestCase):
 
   def setUp(self):
-    self.device_utils = mock.MagicMock()
+    test_serial = '0123456789abcdef'
+    self.adb = mock.Mock(spec=adb_wrapper.AdbWrapper)
+    self.adb.__str__ = mock.Mock(return_value=test_serial)
+    self.watchMethodCalls(self.call.adb)
+
+  def mockShellCall(self, cmd_prefix, action=''):
+    """Expect an adb.Shell(cmd) call with cmd_prefix and do some action
+
+    Args:
+      cmd_prefix: A string, the cmd of the received call is expected to have
+          this as a prefix.
+      action: If callable, an action to perform when the expected call is
+          received, otherwise a return value.
+    Returns:
+      An (expected_call, action) pair suitable for use in assertCalls.
+    """
+    def check_and_return(cmd):
+      self.assertTrue(
+          cmd.startswith(cmd_prefix),
+          'command %r does not start with prefix %r' % (cmd, cmd_prefix))
+      if callable(action):
+        return action(cmd)
+      else:
+        return action
+    return (self.call.adb.Shell(mock.ANY), check_and_return)
+
+  def mockExistsTest(self, exists_result):
+    def action(cmd):
+      if exists_result:
+        return ''
+      else:
+        raise device_errors.AdbCommandFailedError(
+            cmd, 'File not found', 1, str(self.adb))
+    return self.mockShellCall('test -e ', action)
 
   def testTempFileNameAlreadyExists(self):
-    self.device_utils.GetExternalStoragePath.return_value = '/sdcard'
-    self.device_utils.FileExists.side_effect = [True, True, True, False]
-
-    tmpfile = device_temp_file.DeviceTempFile(self.device_utils)
-    logging.debug('Temp file name: %s' % tmpfile.name)
-    self.assertEqual(self.device_utils.FileExists.call_count, 4)
-    self.device_utils.WriteFile.assert_called_with(tmpfile.name, '')
+    with self.assertCalls(
+        self.mockShellCall('echo $EXTERNAL_STORAGE', '/sdcard'),
+        self.mockShellCall('test -d /sdcard'),
+        self.mockExistsTest(True),
+        self.mockExistsTest(True),
+        self.mockExistsTest(True),
+        self.mockExistsTest(False),
+        self.mockShellCall('touch '),
+        self.mockShellCall('rm -f ')):
+      with device_temp_file.DeviceTempFile(self.adb) as tmpfile:
+        logging.debug('Temp file name: %s' % tmpfile.name)
 
   def testTempFileLifecycle(self):
-    self.device_utils.GetExternalStoragePath.return_value = '/sdcard'
-    self.device_utils.FileExists.return_value = False
-
-    with device_temp_file.DeviceTempFile(self.device_utils) as tmpfile:
-      filename = tmpfile.name
-      self.assertEqual(self.device_utils.WriteFile.call_count, 1)
-      self.assertNotEqual(self.device_utils.RunShellCommand.call_args,
-          mock.call(['rm', mock.ANY]))
-
-    self.assertEqual(self.device_utils.RunShellCommand.call_args,
-        mock.call(['rm', filename]))
+    with self.assertCalls(
+        self.mockShellCall('echo $EXTERNAL_STORAGE', '/sdcard'),
+        self.mockShellCall('test -d /sdcard'),
+        self.mockExistsTest(False),
+        self.mockShellCall('touch ')):
+      tempFileContextManager = device_temp_file.DeviceTempFile(self.adb)
+    with mock.patch.object(self.adb, 'Shell'):
+      with tempFileContextManager as tmpfile:
+        logging.debug('Temp file name: %s' % tmpfile.name)
+        self.assertEquals(0, self.adb.Shell.call_count)
+      self.assertEquals(1, self.adb.Shell.call_count)
+      args, _ = self.adb.Shell.call_args
+      self.assertTrue(args[0].startswith('rm -f '))
 
 if __name__ == '__main__':
   logging.getLogger().setLevel(logging.DEBUG)
   unittest.main(verbosity=2)