Book Image

Test-Driven Python Development

By : Siddharta Govindaraj
Book Image

Test-Driven Python Development

By: Siddharta Govindaraj

Overview of this book

This book starts with a look at the test-driven development process, and how it is different from the traditional way of writing code. All the concepts are presented in the context of a real application that is developed in a step-by-step manner over the course of the book. While exploring the common types of smelly code, we will go back into our example project and clean up the smells that we find. Additionally, we will use mocking to implement the parts of our example project that depend on other systems. Towards the end of the book, we'll take a look at the most common patterns and anti-patterns associated with test-driven development, including integration of test results into the development process.
Table of Contents (20 chapters)
Test-Driven Python Development
About the Author
About the Reviewers


It is now time to put our newly-learned skills into practice. Here is a new requirement to build into the Stock class:

  • Sometimes, updates might come out of order and we might get an update for a newer timestamp, followed by an update for an older timestamp. This could be due to random network latency, or due to the fact that sometimes we might get updates from different sources and one might be slightly ahead of the other.

  • The Stock class should be able to handle such cases, and the price attribute should return the latest price as per the timestamp.

  • The is_increasing_trend should also process the latest three prices as per their timestamps.

Try your hand at implementing this requirement. Do not make any changes to the existing interfaces for these methods, but feel free to make any changes to the implementation as you require. Here are some things to think about:

  • Does our existing design support this new feature? Do we need to make any changes to the current design?

  • What kind of tests...