The Complete Rust Programming Reference Guide

Documentation tests

It's often a good practice to include code examples with any documentation for your crate's public APIs. There's a caveat in maintaining such examples, though. Your code might change and you might forget to update your examples. Documentation tests (doctests) are there to remind you to update your example code as well. Rust allows you to embed code in backticks within doc comments. Cargo can then run this example code that's been embedded within your documentation, and treats it as part of the unit test suite. This means that documentation examples run every time you run your unit tests, forcing you to update them. Quite amazing!

Documentation tests are also executed via Cargo. We have created a project called doctest_demo ...