Revert of Android: Trust large random numbers for temp files

build/android/devil/android/device_temp_file_test.py

Index: build/android/devil/android/device_temp_file_test.py
diff --git a/build/android/devil/android/device_temp_file_test.py b/build/android/devil/android/device_temp_file_test.py
new file mode 100755
index 0000000000000000000000000000000000000000..76f9cc8ec0179984831eff7fd3028299487fc3e3
--- /dev/null
+++ b/build/android/devil/android/device_temp_file_test.py
@@ -0,0 +1,91 @@
+#!/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 devil.android import device_errors
+from devil.android import device_temp_file
+from devil.android.sdk import adb_wrapper
+from devil.utils import mock_calls
+from pylib import constants
+
+sys.path.append(os.path.join(
+    constants.DIR_SOURCE_ROOT, 'third_party', 'pymock'))
+import mock # pylint: disable=F0401
+
+class DeviceTempFileTest(mock_calls.TestCase):
+
+  def setUp(self):
+    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):
+    with self.assertCalls(
+        self.mockShellCall('test -d /data/local/tmp'),
+        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):
+    with self.assertCalls(
+        self.mockShellCall('test -d /data/local/tmp'),
+        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)