Deletion

Original source

This tests the property "if we remove an element from a list, the element is no longer in the list". The remove function we use however only actually removes the first instance of the element, so this fails whenever the list contains a duplicate and we try to remove one of those elements.

This example is interesting for a couple of reasons:

1. It's a nice easy to explain example of property-based testing.
2. Shrinking duplicates simultaneously is something that most property-based testing libraries can't do.

The expected smallest falsified sample is ([0, 0], 0).

Implementors

Library	Code	Report
Americium	DeletionTest.java	deletion.md
jqwik	DeletionProperties.java	deletion.md
fast-check	deletion.js	deletion.md
CsCheck	ShrinkingChallengeTests.cs	deletion.md
elm-test	Deletion.elm	deletion.md