test-assertions

Test assertions

The Rust testing framework provides macros for test assertions, such as:

• assert!(condition): assert condition is true.

• assert_eq!(a, b): assert a is equal to b.

• assert_ne!(a, b): assert a is not equal to b.

Example:

let x = 1;
let y = 2;
assert!(x < y);

Example with an optional message:

let x = 1;
let y = 2;
assert!(x < y, "We want x to be less than y");

Assertables crate

The Assertables crate provides more assert macros, such as:

• assert_starts_with!(x, y): Does x start with y?

• assert_contains!(array, element): Does array contains element?

• assert_is_match!(regex, string): Does regex match string?

Example:

use assertables;
let a = "hello world";
let b = "hello";
assert_starts_with!(&a, &b);