Reland of Migrate DeviceUtils.ReadFile to adb_wrapper (try 3)

build/android/pylib/device/device_utils_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_utils.py (mostly DeviceUtils).
 """
 
 # pylint: disable=C0321
@@ skipping 1031 matching lines @@
     with mock.patch('os.path.exists', return_value=True):
       with self.assertCall(
           self.call.adb.Pull('/data/app/test.file.does.not.exist',
                              '/test/file/host/path'),
           self.CommandError('remote object does not exist')):
         with self.assertRaises(device_errors.CommandFailedError):
           self.device.PullFile('/data/app/test.file.does.not.exist',
                                '/test/file/host/path')
 
 
-class DeviceUtilsReadFileTest(DeviceUtilsOldImplTest):
+class DeviceUtilsReadFileTest(DeviceUtilsNewImplTest):
 
   def testReadFile_exists(self):
-    with self.assertCallsSequence([
-        ("adb -s 0123456789abcdef shell "
-            "'cat \"/read/this/test/file\" 2>/dev/null'",
-         'this is a test file')]):
-      self.assertEqual(['this is a test file'],
+    with self.assertCall(
+        self.call.adb.Shell('cat /read/this/test/file'),
+        'this is a test file\r\n'):
+      self.assertEqual('this is a test file\n',
                        self.device.ReadFile('/read/this/test/file'))
 
   def testReadFile_doesNotExist(self):
+    with self.assertCall(
+        self.call.adb.Shell('cat /this/file/does.not.exist'),
+        self.ShellError('/system/bin/sh: cat: /this/file/does.not.exist: '
+                        'No such file or directory')):
+      with self.assertRaises(device_errors.AdbCommandFailedError):
+        self.device.ReadFile('/this/file/does.not.exist')
+
+  def testReadFile_withSU(self):
     with self.assertCalls(
-        "adb -s 0123456789abcdef shell "
-            "'cat \"/this/file/does.not.exist\" 2>/dev/null'",
-         ''):
-      self.device.ReadFile('/this/file/does.not.exist')
-
-  def testReadFile_asRoot_withRoot(self):
-    self.device.old_interface._privileged_command_runner = (
-        self.device.old_interface.RunShellCommand)
-    self.device.old_interface._protected_file_access_method_initialized = True
-    with self.assertCallsSequence([
-        ("adb -s 0123456789abcdef shell "
-            "'cat \"/this/file/must.be.read.by.root\" 2> /dev/null'",
-         'this is a test file\nread by root')]):
+      (self.call.device.NeedsSU(), True),
+      (self.call.adb.Shell("su -c sh -c 'cat /this/file/can.be.read.with.su'"),
+       'this is a test file\nread with su')):
       self.assertEqual(
-          ['this is a test file', 'read by root'],
-          self.device.ReadFile('/this/file/must.be.read.by.root',
-                               as_root=True))
-
-  def testReadFile_asRoot_withSu(self):
-    self.device.old_interface._privileged_command_runner = (
-        self.device.old_interface.RunShellCommandWithSU)
-    self.device.old_interface._protected_file_access_method_initialized = True
-    with self.assertCallsSequence([
-        ("adb -s 0123456789abcdef shell "
-            "'su -c cat \"/this/file/can.be.read.with.su\" 2> /dev/null'",
-         'this is a test file\nread with su')]):
-      self.assertEqual(
-          ['this is a test file', 'read with su'],
+          'this is a test file\nread with su\n',
           self.device.ReadFile('/this/file/can.be.read.with.su',
                                as_root=True))
 
-  def testReadFile_asRoot_rejected(self):
-    self.device.old_interface._privileged_command_runner = None
-    self.device.old_interface._protected_file_access_method_initialized = True
-    with self.assertRaises(device_errors.CommandFailedError):
-      self.device.ReadFile('/this/file/cannot.be.read.by.user',
-                           as_root=True)
-
 
 class DeviceUtilsWriteFileTest(DeviceUtilsNewImplTest):
 
   def testWriteFile_withPush(self):
     tmp_host = MockTempFile('/tmp/file/on.host')
     contents = 'some large contents ' * 26 # 20 * 26 = 520 chars
     with self.assertCalls(
         (mock.call.tempfile.NamedTemporaryFile(), tmp_host),
         self.call.adb.Push('/tmp/file/on.host', '/path/to/device/file')):
       self.device.WriteFile('/path/to/device/file', contents)
@@ skipping 353 matching lines @@
       self.assertTrue(
           isinstance(device, device_utils.DeviceUtils)
           and serial == str(device),
           'Expected a DeviceUtils object with serial %s' % serial)
 
 
 if __name__ == '__main__':
   logging.getLogger().setLevel(logging.DEBUG)
   unittest.main(verbosity=2)