Mocking the built-in print function in the decorator tests (#8)

Author: cosmicboy79

src/learning/__init__.py src/decorator/__init__.pysrc/learning/__init__.py renamed to src/decorator/__init__.py

@@ -0,0 +1,69 @@
+"""
+Set of pytests for the @logme decorator.
+
+I used the following reference to understand how to mock the "open" function:
+https://docs.python.org/3.3/library/unittest.mock.html#mock-open
+
+I used the same principle for the "print" function, used in these tests.
+"""
+from unittest.mock import patch
+
+from decorator.logging.mylog import LOG_FILE_NAME, Level, logme
+
+
+@patch("builtins.open", create=True)
+@patch("builtins.print", create=True)
+def test_logme_for_none(mock_print, mock_open):
+    """
+    GIVEN logging for a function
+    WHEN logme is called with no level set
+    THEN there is no writing to output log file
+    """
+    mock_print.__name__ = "print"
+
+    # logme returns a wrapper function for the passed function
+    wrapper = logme(mock_print)()
+
+    # this is where the logic happens
+    wrapper()
+
+    # no writing to log happened
+    mock_open.assert_not_called()
+    # but target function was called
+    mock_print.assert_called_once()
+
+@patch("builtins.open", create=True)
+@patch("builtins.print", create=True)
+def test_logme_for_info(mock_print, mock_open):
+    """
+    GIVEN logging for a function
+    WHEN logme is called with INFO level
+    THEN there is one write call to output log file
+    """
+    mock_print.__name__ = "print"
+
+    # logme returns a wrapper function for the passed function, and I am calling it directly
+    logme(mock_print, level=Level.INFO)()
+
+    # one write call to the log output
+    mock_open.assert_called_with(LOG_FILE_NAME, "a+")
+    # target function was called
+    mock_print.assert_called_once()
+
+@patch("builtins.open", create=True)
+@patch("builtins.print", create=True)
+def test_logme_for_debug(mock_print, mock_open):
+    """
+    GIVEN logging for a function
+    WHEN logme is called with INFO level
+    THEN there are two write calls to output log file
+    """
+    mock_print.__name__ = "print"
+
+    # logme returns a wrapper function for the passed function, and I am calling it directly
+    logme(print, level=Level.DEBUG)()
+
+    # in this case, two write calls to the log output
+    assert mock_open.call_count == 2
+    # target function was called
+    mock_print.assert_called_once()

src/learning/logging/__init__.py src/decorator/logging/__init__.pysrc/learning/logging/__init__.py renamed to src/decorator/logging/__init__.py

@@ -1,3 +1,6 @@
+"""
+Using the @logme decorator.
+"""
 from logging.mylog import logme, Level
 
 @logme