Macro assert_matches 

macro_rules! assert_matches {
    ($expression:expr, $pattern:pat if $guard:expr, $($arg:tt)+) => { ... };
    ($expression:expr, $pattern:pat if $guard:expr $(,)?) => { ... };
    ($expression:expr, $pattern:pat, $($arg:tt)+) => { ... };
    ($expression:expr, $pattern:pat $(,)?) => { ... };
}

Asserts that an expression matches a given pattern.

This is a stable polyfill for assert_matches! that ensures 100% region coverage. Unlike the crate or standard library macros, this implementation avoids generating unreachable panic branches that llvm-cov flags as uncovered regions.

Examples

use libcnb_test::assert_matches;

let result: Result<i32, String> = Ok(42);

// Simple pattern matching
assert_matches!(result, Ok(_));

// With guard
assert_matches!(result, Ok(x) if x > 40);

// With custom error message
assert_matches!(result, Ok(x) if x > 40, "value should be greater than 40");