Documentation comment code blocks can use annotations with attributes that help rustdoc do the right thing when testing your code. Here are the annotations.
This test must panic:
/// ```should_panic
/// assert!(false);
/// ```This test must compile, but is not run:
/// ```no_run
/// assert!(true);
/// ```This test must fail to compile:
/// ```compile_fail
/// snafu
/// ```This test is only for Rust 2018 edition:
/// ```edition2018
/// assert!(true);
/// ```This code block is ignored, and not a test:
/// ```ignore
/// This is something else besides a test.
/// ```This code block is text, and not a test:
/// ```text
/// Hello, World!
/// ```