[Telemetry] Add pyfakefs to telemetry/third_party

tools/telemetry/third_party/pyfakefs/pyfakefs/example_test.py

+#! /usr/bin/env python
+#
+# Copyright 2014 Altera Corporation. All Rights Reserved.
+# Author: John McGehee
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Test the :py:class`pyfakefs.example` module to demonstrate the usage of the
+:py:class`pyfakefs.fake_filesystem_unittest.TestCase` base class.
+"""
+
+import os
+import sys
+if sys.version_info < (2, 7):
+    import unittest2 as unittest
+else:
+    import unittest
+
+import fake_filesystem_unittest
+# The module under test is pyfakefs.example
+import example
+
+
+def load_tests(loader, tests, ignore):
+    '''Load the pyfakefs/example.py doctest tests into unittest.'''
+    return fake_filesystem_unittest.load_doctests(loader, tests, ignore, example)
+
+
+class TestExample(fake_filesystem_unittest.TestCase): # pylint: disable=R0904
+    '''Test the pyfakefs.example module.'''
+
+    def setUp(self):
+        '''Invoke the :py:class:`pyfakefs.fake_filesystem_unittest.TestCase`
+        `self.setUp()` method.  This defines:
+        
+        * Attribute `self.fs`, an instance of \
+          :py:class:`pyfakefs.fake_filesystem.FakeFilesystem`.  This is useful \
+          for creating test files.
+        * Attribute `self.stubs`, an instance of \
+          :py:class:`mox.stubout.StubOutForTesting`.  Use this if you need to
+          define additional stubs.
+        '''
+        self.setUpPyfakefs()
+
+    def tearDown(self):
+        # No longer need self.tearDownPyfakefs()
+        pass
+        
+    def test_create_file(self):
+        '''Test example.create_file()'''
+        # The os module has been replaced with the fake os module so all of the
+        # following occurs in the fake filesystem.
+        self.assertFalse(os.path.isdir('/test'))
+        os.mkdir('/test')
+        self.assertTrue(os.path.isdir('/test'))
+        
+        self.assertFalse(os.path.exists('/test/file.txt'))
+        example.create_file('/test/file.txt')
+        self.assertTrue(os.path.exists('/test/file.txt'))
+        
+    def test_delete_file(self):
+        '''Test example.delete_file()
+
+        `self.fs.CreateFile()` is convenient because it automatically creates
+        directories in the fake file system and allows you to specify the file
+        contents.
+        
+        You could also use `open()` or `file()`.
+        '''
+        self.fs.CreateFile('/test/full.txt',
+                           contents='First line\n'
+                                    'Second Line\n')
+        self.assertTrue(os.path.exists('/test/full.txt'))
+        example.delete_file('/test/full.txt')
+        self.assertFalse(os.path.exists('/test/full.txt'))
+
+    def test_file_exists(self):
+        '''Test example.path_exists()
+
+        `self.fs.CreateFile()` is convenient because it automatically creates
+        directories in the fake file system and allows you to specify the file
+        contents.
+        
+        You could also use `open()` or `file()` if you wanted.
+        '''
+        self.assertFalse(example.path_exists('/test/empty.txt'))          
+        self.fs.CreateFile('/test/empty.txt')
+        self.assertTrue(example.path_exists('/test/empty.txt'))              
+        
+    def test_get_globs(self):
+        '''Test example.get_glob()
+        
+        `self.fs.CreateDirectory()` creates directories.  However, you might
+        prefer the familiar `os.makedirs()`, which also works fine on the fake
+        file system.
+        '''
+        self.assertFalse(os.path.isdir('/test'))
+        self.fs.CreateDirectory('/test/dir1/dir2a')
+        self.assertTrue(os.path.isdir('/test/dir1/dir2a'))
+        # os.mkdirs() works, too.
+        os.makedirs('/test/dir1/dir2b')
+        self.assertTrue(os.path.isdir('/test/dir1/dir2b'))
+        
+        self.assertItemsEqual(example.get_glob('/test/dir1/nonexistent*'),
+                              [])
+        self.assertItemsEqual(example.get_glob('/test/dir1/dir*'),
+                              ['/test/dir1/dir2a', '/test/dir1/dir2b'])
+
+    def test_rm_tree(self):
+        '''Test example.rm_tree()
+        
+        `self.fs.CreateDirectory()` creates directories.  However, you might
+        prefer the familiar `os.makedirs()`, which also works fine on the fake
+        file system.
+        '''
+        self.fs.CreateDirectory('/test/dir1/dir2a')
+        # os.mkdirs() works, too.
+        os.makedirs('/test/dir1/dir2b')
+        self.assertTrue(os.path.isdir('/test/dir1/dir2b'))
+        self.assertTrue(os.path.isdir('/test/dir1/dir2a'))
+       
+        example.rm_tree('/test/dir1')
+        self.assertFalse(os.path.exists('/test/dir1'))
+
+if __name__ == "__main__":
+    unittest.main()