1# Copyright 2014 Altera Corporation. All Rights Reserved. 2# Author: John McGehee 3# 4# Licensed under the Apache License, Version 2.0 (the "License"); 5# you may not use this file except in compliance with the License. 6# You may obtain a copy of the License at 7# 8# http://www.apache.org/licenses/LICENSE-2.0 9# 10# Unless required by applicable law or agreed to in writing, software 11# distributed under the License is distributed on an "AS IS" BASIS, 12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13# See the License for the specific language governing permissions and 14# limitations under the License. 15 16""" 17Test the :py:class`pyfakefs.example` module to demonstrate the usage of the 18:py:class`pyfakefs.fake_filesystem_unittest.TestCase` base class. 19 20Fake filesystem functions like `create_file()`, `create_dir()` or 21`create_symlink()` are often used to set up file structures at the beginning 22of a test. 23While you could also use the familiar `open()`, `os.mkdirs()` and similar 24functions, these functions can make the test code shorter and more readable. 25`create_file()` is particularly convenient because it creates all parent 26directories and allows you to specify the contents or the size of the file. 27""" 28 29import io 30import os 31import sys 32import unittest 33 34from pyfakefs import fake_filesystem_unittest 35from pyfakefs.extra_packages import use_scandir_package 36from pyfakefs.tests import example # The module under test 37 38 39def load_tests(loader, tests, ignore): 40 """Load the pyfakefs/example.py doctest tests into unittest.""" 41 return fake_filesystem_unittest.load_doctests( 42 loader, tests, ignore, example) 43 44 45class TestExample(fake_filesystem_unittest.TestCase): # pylint: disable=R0904 46 """Test the example module. 47 The os and shutil modules have been replaced with the fake modules, 48 so that all of the calls to os and shutil in the tested example code 49 occur in the fake filesystem. 50 """ 51 52 def setUp(self): 53 """Invoke the :py:class:`pyfakefs.fake_filesystem_unittest.TestCase` 54 `self.setUp()` method. This defines: 55 56 * Attribute `self.fs`, an instance of 57 :py:class:`pyfakefs.fake_filesystem.FakeFilesystem`. This is useful 58 for creating test files. 59 * Attribute `self.stubs`, an instance of 60 :py:class:`pyfakefs.mox3_stubout.StubOutForTesting`. Use this if 61 you need to define additional stubs. 62 """ 63 64 # This is before setUpPyfakefs(), so still using the real file system 65 self.filepath = os.path.realpath(__file__) 66 with io.open(self.filepath, 'rb') as f: 67 self.real_contents = f.read() 68 69 self.setUpPyfakefs() 70 71 def tearDown(self): 72 # No longer need self.tearDownPyfakefs() 73 pass 74 75 def test_create_file(self): 76 """Test example.create_file() which uses `open()` and `file.write()`. 77 """ 78 self.assertFalse(os.path.isdir('/test')) 79 os.mkdir('/test') 80 self.assertTrue(os.path.isdir('/test')) 81 82 self.assertFalse(os.path.exists('/test/file.txt')) 83 example.create_file('/test/file.txt') 84 self.assertTrue(os.path.exists('/test/file.txt')) 85 86 def test_delete_file(self): 87 """Test example.delete_file() which uses `os.remove()`.""" 88 self.fs.create_file('/test/full.txt', 89 contents='First line\n' 90 'Second Line\n') 91 self.assertTrue(os.path.exists('/test/full.txt')) 92 example.delete_file('/test/full.txt') 93 self.assertFalse(os.path.exists('/test/full.txt')) 94 95 def test_file_exists(self): 96 """Test example.path_exists() which uses `os.path.exists()`.""" 97 self.assertFalse(example.path_exists('/test/empty.txt')) 98 self.fs.create_file('/test/empty.txt') 99 self.assertTrue(example.path_exists('/test/empty.txt')) 100 101 def test_get_globs(self): 102 """Test example.get_glob().""" 103 self.assertFalse(os.path.isdir('/test')) 104 self.fs.create_dir('/test/dir1/dir2a') 105 self.assertTrue(os.path.isdir('/test/dir1/dir2a')) 106 # os.mkdirs() works, too. 107 os.makedirs('/test/dir1/dir2b') 108 self.assertTrue(os.path.isdir('/test/dir1/dir2b')) 109 110 self.assertEqual(example.get_glob('/test/dir1/nonexistent*'), 111 []) 112 is_windows = sys.platform.startswith('win') 113 matching_paths = sorted(example.get_glob('/test/dir1/dir*')) 114 if is_windows: 115 self.assertEqual(matching_paths, 116 [r'\test\dir1\dir2a', r'\test\dir1\dir2b']) 117 else: 118 self.assertEqual(matching_paths, 119 ['/test/dir1/dir2a', '/test/dir1/dir2b']) 120 121 def test_rm_tree(self): 122 """Test example.rm_tree() using `shutil.rmtree()`.""" 123 self.fs.create_dir('/test/dir1/dir2a') 124 # os.mkdirs() works, too. 125 os.makedirs('/test/dir1/dir2b') 126 self.assertTrue(os.path.isdir('/test/dir1/dir2b')) 127 self.assertTrue(os.path.isdir('/test/dir1/dir2a')) 128 129 example.rm_tree('/test/dir1') 130 self.assertFalse(os.path.exists('/test/dir1')) 131 132 def test_os_scandir(self): 133 """Test example.scandir() which uses `os.scandir()`. 134 135 The os module has been replaced with the fake os module so the 136 fake filesystem path entries are returned instead of `os.DirEntry` 137 objects. 138 """ 139 self.fs.create_file('/test/text.txt') 140 self.fs.create_dir('/test/dir') 141 self.fs.create_file('/linktest/linked') 142 self.fs.create_symlink('/test/linked_file', '/linktest/linked') 143 144 entries = sorted(example.scan_dir('/test'), key=lambda e: e.name) 145 self.assertEqual(3, len(entries)) 146 self.assertEqual('linked_file', entries[1].name) 147 self.assertTrue(entries[0].is_dir()) 148 self.assertTrue(entries[1].is_symlink()) 149 self.assertTrue(entries[2].is_file()) 150 151 @unittest.skipIf(not use_scandir_package, 152 'Testing only if scandir module is installed') 153 def test_scandir_scandir(self): 154 """Test example.scandir() which uses `scandir.scandir()`. 155 156 The scandir module has been replaced with the fake_scandir module so 157 the fake filesystem path entries are returned instead of 158 `scandir.DirEntry` objects. 159 """ 160 self.fs.create_file('/test/text.txt') 161 self.fs.create_dir('/test/dir') 162 163 entries = sorted(example.scan_dir('/test'), key=lambda e: e.name) 164 self.assertEqual(2, len(entries)) 165 self.assertEqual('text.txt', entries[1].name) 166 self.assertTrue(entries[0].is_dir()) 167 self.assertTrue(entries[1].is_file()) 168 169 def test_real_file_access(self): 170 """Test `example.file_contents()` for a real file after adding it using 171 `add_real_file()`.""" 172 with self.assertRaises(OSError): 173 example.file_contents(self.filepath) 174 self.fs.add_real_file(self.filepath) 175 self.assertEqual(example.file_contents(self.filepath), 176 self.real_contents) 177 178 179if __name__ == "__main__": 180 unittest.main() 181