Book Image

Python GUI programming with Tkinter

By : Alan D. Moore
Book Image

Python GUI programming with Tkinter

By: Alan D. Moore

Overview of this book

Tkinter is a lightweight, portable, and easy-to-use graphical toolkit available in the Python Standard Library, widely used to build Python GUIs due to its simplicity and availability. This book teaches you to design and build graphical user interfaces that are functional, appealing, and user-friendly using the powerful combination of Python and Tkinter. After being introduced to Tkinter, you will be guided step-by-step through the application development process. Over the course of the book, your application will evolve from a simple data-entry form to a complex data management and visualization tool while maintaining a clean and robust design. In addition to building the GUI, you'll learn how to connect to external databases and network resources, test your code to avoid errors, and maximize performance using asynchronous programming. You'll make the most of Tkinter's cross-platform availability by learning how to maintain compatibility, mimic platform-native look and feel, and build executables for deployment across popular computing platforms. By the end of this book, you will have the skills and confidence to design and build powerful high-end GUI applications to solve real-world problems.
Table of Contents (23 chapters)
Title Page
Copyright and Credits
Packt Upsell

Writing tests for our application

Let's put our knowledge of unittest to work and write some tests for our application. To get started, we need to create a test module for our application. Make a directory called test inside the abq_data_entry package, and create the customary empty file inside. We'll create all of our test modules inside this directory.

Testing our model

Our CSVModel code is fairly self-contained apart from its need to read and write files. Since file operations are one of the more common things that need to be mocked out in a test, the mock module provides mock_open, a Mock subclass ready-made to replace Python's open method. When called, a mock_open object returns a mock file handle object, complete with support for the read(), write(), and readlines() methods.

Let's begin creating our test case class in test/ as follows:

from .. import models
from unittest import TestCase
from unittest import mock

class TestCSVModel(TestCase):
    def setUp(self...