HomeCoursesProperty-Based Testing with PropEr in Elixir

Intermediate

17h 30min

Property-Based Testing with PropEr in Elixir

Gain insights into property-based testing with PropEr in Elixir. Learn foundational principles, custom data generators, and advanced concepts for effective real-world application testing.

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Overview

Content

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Property-based testing relies on specifying some property of code, unlike unit tests, which specify the expected output in response to some inputs. In this course, we'll cover the concepts we need to feel confident about using even the most advanced features of PropEr with Elixir. We'll start with the basic and foundational principles of property-based testing, see what the framework offers us to get started, make our way through thinking in properties, write our own custom data generators, and then learn more advanced concepts. We'll also see how you can use property-based testing in a realistic project. By the time we finish this course, we should feel comfortable testing real-world applications using properties.

Property-based testing relies on specifying some property of code, unlike unit tests, which specify the expected output in respo...Show More

WHAT YOU'LL LEARN

Understand the concepts of PropEr.

Understand the role of generators in property in property-based testing.

Have a clear sense where property-based testing has an advantage over Eunit tests and vice versa.

Be able to use stateful properties with ease.

Learn how to write State Machine Properties.

Understand property-based testing

Understand the concepts of PropEr.

Content

88 Lessons5 Quizzes

Foundations of Property-Based Testing

5 Lessons

Get familiar with property-based testing principles, frameworks, and their implementation in Elixir.

Why Property-based Testing?

Properties

Property-Based Testing in a Project

Running a Property

Wrapping Up

Writing Properties

8 Lessons

Look at writing properties, file and property structures, execution models, and default generators.

Introduction to Writing Properties

Putting It All Together

Wrapping Up

Quiz Yourself on Writing Properties

Thinking in Properties

8 Lessons

Explore transitioning to property-based testing with modeling, generalizing tests, invariants, and symmetric properties.

Introduction to Thinking in Properties

Modeling

Generalizing Test Examples

Invariants

Symmetric Properties

Putting It All Together

Wrapping Up

Quiz Yourself on Thinking in Properties

Custom Generators

13 Lessons

Break down complex ideas of custom generators for comprehensive property-based testing.

Introduction to Custom Generators

Gathering Statistics: Collecting

Gathering Statistics: Aggregating

Basic Custom Generators

Resizing Generators

Transforming Generators

Imposing Restrictions

Changing Probabilities

Fancy Custom Generators

Recursive Generators

Symbolic Calls

Wrapping Up

Quiz Yourself on Custom Generators

Responsible Testing

9 Lessons

Take a closer look at responsible testing with Elixir, emphasizing adaptable unit testing and CSV parsing.

Introduction to Responsible Testing

The Program Structure

CSV Parsing: The Property

CSV Parsing: The CSV Parser

Filtering Records

Employee Module

Templating

Putting It All Together

Wrapping Up

Properties-Driven Development

9 Lessons

Focus on defining and validating properties, handling special pricing, and using negative testing.

Introduction to Properties-driven Development

Writing the First Property

Testing Specials

Generating Specials

Implementing Specials

Negative Testing: Broad Properties

Negative Testing: Calibrating Negative Properties

Negative Testing: Relaxing Constraints

Wrapping Up

Shrinking

5 Lessons

Master the steps to optimize counterexample handling in PropEr using the shrink and let_shrink macros.

Introduction to Shrinking

Re-centering with shrink

Dividing with let_shrink

Wrapping Up

Quiz Yourself on Shrinking

Stateful Properties

8 Lessons

Learn how to use stateful property-based testing for verifying complex system behaviors.

Introduction to Stateful Properties

How Stateful Properties Run

Writing Stateful Properties

Testing a Basic Concurrent Cache: Implementation

Testing a Basic Concurrent Cache: Writing Tests

Testing Parallel Executions

Wrapping Up

Quiz Yourself on Stateful Properties

Case Study: Bookstore

11 Lessons

Get started with testing a PostgreSQL-based bookstore in Elixir, focusing on stateful properties.

Introducing the Application

The Application: Getting Started

The Application: The Database Module

The Application: Running the Code

Writing Generators

Broad Stateful Testing

Precise Stateful Modelling

Refining the Tests

Debugging Stateful Properties

Parallel Tests

Wrapping Up

10.

State Machine Properties

11 Lessons

Examine finite state machines for robust testing, focusing on circuit breakers and model adjustments.

Introduction to State Machine Properties

Laying Out State Machine Properties

How State Machine Properties Run

Writing FSM Properties

Testing a Circuit Breaker

Modeling the Circuit Breaker: The Shim Module

Modeling the Circuit Breaker: The Property

Modeling the Circuit Breaker: The Test Module

Adjusting the Model: Fixing the Issue

Adjusting the Model: Better Statistics

Wrapping Up

11.

Conclusion

1 Lessons

Apply your skills to implement property-based testing for improved software quality and reliability.

Conclusion

Certificate of Completion

Showcase your accomplishment by sharing your certificate of completion.

Course Author:

The Pragmatic Programmers

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