level2

context_manager/answers/change_directory.py

@@ -0,0 +1,30 @@
+import os
+from contextlib import contextmanager
+
+
+def change_dir_without_context_manager(filename1, filename2):
+    cwd = os.getcwd()
+    os.chdir(filename1)
+    a = os.listdir()
+    os.chdir(cwd)
+
+    cwd = os.getcwd()
+    os.chdir(filename2)
+    b = os.listdir()
+    os.chdir(cwd)
+    return a + b
+
+
+@contextmanager
+def change_dir(filename):
+    try:
+        cwd = os.getcwd()
+        os.chdir(filename)
+        yield
+    finally:
+        os.chdir(cwd)
+
+
+def try_change_dir(filename):
+    with change_dir(filename):
+        return os.listdir()

context_manager/change_directory.py

@@ -0,0 +1,33 @@
+import os
+from contextlib import contextmanager
+
+
+def change_dir_without_context_manager(filename1, filename2):
+   """
+   Changes directory from pwd to pwd/filename.
+   :param filename1: name of first folder
+   :param filename2: name of second folder
+   :return: list if files in filename1 and filename2
+   """
+
+
+"""
+With context manager.
+"""
+
+
+@contextmanager
+def change_dir(filename):
+   """
+   Changes directory from pwd to pwd/filename.
+   :param filename: name of folder
+   """
+
+
+def try_change_dir(filename):
+    """
+    Uses change_dir().
+    :param filename: name of folder
+    :return: list of files in folder
+    """
+

context_manager/instruction.md

@@ -2,7 +2,7 @@
 
 1. Look at the file write_into_file.py
 
-2. Look at the tests in tests folter 
+2. Look at the tests in tests folder 
 
 3. Run tests with command:
 
@@ -18,4 +18,44 @@
 
 7. Congratulations, you have passed first level. Commit and push your changes. 
 
-### LEVEL-2
+### LEVEL-2
+
+1. Look at the file change_directory.py
+
+2. Look at the test_change_directory.py in tests folder 
+
+3. Run tests with command:
+
+    ```python3 -m unittest tests/test_change_directory.py```
+
+   As you see all your tests are failed
+
+4. Now, complete the functions in change_directory.py
+
+5. Run tests and all of them should be passed.
+
+6. Compare your answer with mine located in answers/change_directory.py
+
+7. Congratulations, you have passed second level. Commit and push your changes. 
+
+### LEVEL-3
+
+1. Look at the file change_directory.py
+
+2. Look at the test_change_directory.py in tests folder 
+
+3. Run tests with command:
+
+    ```python3 -m unittest tests/test_change_directory.py```
+
+   As you see all your tests are failed
+
+4. Now, complete the functions in change_directory.py
+
+5. Run tests and all of them should be passed.
+
+6. Compare your answer with mine located in answers/change_directory.py
+
+7. Congratulations, you have passed second level. Commit and push your changes. 
+
+

context_manager/tests/test_change_directory.py

@@ -0,0 +1,27 @@
+from unittest import TestCase
+from change_directory import (
+    change_dir_without_context_manager,
+    try_change_dir
+)
+
+class ContextManagerTest(TestCase):
+    def test_change_dir_without(self):
+        result = change_dir_without_context_manager('file_one','file_two')
+        self.assertEqual(result, ['love.txt', 'context.txt', 'I.txt', 'manager.txt', 'love.txt', 'and.txt', 'I.txt', 'beshbarmak.txt'])
+
+    def test_change_dir_without1(self):
+        result = change_dir_without_context_manager('file_one', 'file_one')
+        self.assertEqual(result, ['love.txt', 'context.txt', 'I.txt', 'manager.txt', 'love.txt', 'context.txt', 'I.txt', 'manager.txt'])
+
+    def test_change_dir_without2(self):
+        result = change_dir_without_context_manager('file_two', 'file_two')
+        self.assertEqual(result, ['love.txt', 'and.txt', 'I.txt', 'beshbarmak.txt', 'love.txt', 'and.txt', 'I.txt', 'beshbarmak.txt'])
+
+
+    def test_change_dir_with(self):
+        result = try_change_dir('file_one')
+        self.assertEqual(result, ['love.txt', 'context.txt', 'I.txt', 'manager.txt'])
+
+    def test_change_dir_with1(self):
+        result = try_change_dir('file_two')
+        self.assertEqual(result,['love.txt', 'and.txt', 'I.txt', 'beshbarmak.txt'])