Macro claim::assert_ready_eq
source · [−]macro_rules! assert_ready_eq {
($cond:expr, $expected:expr,) => { ... };
($cond:expr, $expected:expr) => { ... };
($cond:expr, $expected:expr, $($arg:tt)+) => { ... };
}
Expand description
Asserts that left expression returns [Poll::Ready(T)
] variant
and its value of T
type equals to the right expression.
This macro is available for Rust 1.36+.
Uses
Assertions are always checked in both debug and release builds, and cannot be disabled.
See debug_assert_ready_eq!
for assertions that are not enabled in release builds by default.
Custom messages
This macro has a second form, where a custom panic message can be provided
with or without arguments for formatting. See std::fmt
for syntax for this form.
Examples
let res: Poll<Result<i32, ()>> = Poll::Ready(Ok(42));
assert_ready_eq!(res, Ok(42));
Value of T
type from the Poll::Ready(T)
will also be returned from this macro call:
let res: Poll<Result<i32, ()>> = Poll::Ready(Ok(42));
let value = assert_ready_eq!(res, Ok(42));
assert_eq!(value, Ok(42));
Poll::Pending
variant will cause panic:
ⓘ
let res: Poll<Result<i32, ()>> = Poll::Pending;
assert_ready_eq!(res, Ok(42)); // Will panic