Property Based Testing

[Danwhy]

Property based tests are tests that assert certain properties are always satisfied by your code. Instead of just testing that your code works on one input, they provide a range of inputs, making sure the property is satisfied every time. This article is a good introduction to property based testing in general.

Property based testing is very popular among the functional language community, including Elixir.

Articles

• https://elixir-lang.org/blog/2017/10/31/stream-data-property-based-testing-and-data-generation-for-elixir/
• https://jeffkreeftmeijer.com/mix-proper/
• http://whatdidilearn.info/2018/04/22/property-based-testing.html

Books

• https://pragprog.com/book/fhproper/property-based-testing-with-proper-erlang-and-elixir

Videos

• https://youtu.be/x2ckfhqB9nA?t=1964 - Keynote - José Valim - ElixirConf EU 2018
• https://www.youtube.com/watch?v=p84DMv8TQuo - Property-based Testing is a Mindset - Andrea Leopardi - ElixirConf EU 2018

[nelsonic]

Property based testing in JavaScript with JSVerify: https://hackernoon.com/property-based-testing-4330e3e77381

I'm not recommending that anyone write JS long term, this is relevant to anyone who is not yet fluent in Elixir/Elm or people who are stuck in JS-land for whatever reason. see: https://github.com/jsverify/jsverify

"Testing shows the presence, not the absence of bugs". ~ Edsger W. Dijkstra

[Danwhy]

ElixirConf 2018 - Picking Properties to Test in Property Based Testing - Michael Stalker

[Danwhy]

Guide coming soon: https://github.com/dwyl/learn-property-based-testing