Macro assertables::assert_contains

source · 
macro_rules! assert_contains {
    ($container:expr, $containee:expr $(,)?) => { ... };
    ($container:expr, $containee:expr, $($message:tt)+) => { ... };
}
Expand description

Assert a container is a match for an expression.

  • If true, return ().

  • Otherwise, call panic! with a message and the values of the expressions with their debug representations.

§Examples

// Return Ok when a string contains a substring
let a = "alfa";
let b = "lf";
assert_contains!(a, b);

// Return Ok when a range contains a value
let a = 1..5;
let b = 2;
assert_contains!(a, &b);

let a = "alfa";
let b = "zz";
assert_contains!(a, b);
// assertion failed: `assert_contains!(container, containee)`
//  container label: `a`,
//  container debug: `\"alfa\"`,
//  containee label: `b`,
//  containee debug: `\"zz\"`

§Module macros