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//@ revisions: unchk_pass chk_pass chk_fail_try chk_fail_ret chk_fail_yeet
//
//@ [unchk_pass] run-pass
//@ [chk_pass] run-pass
//@ [chk_fail_try] run-fail
//@ [chk_fail_ret] run-fail
//@ [chk_fail_yeet] run-fail
//
//@ [unchk_pass] compile-flags: -Zcontract-checks=no
//@ [chk_pass] compile-flags: -Zcontract-checks=yes
//@ [chk_fail_try] compile-flags: -Zcontract-checks=yes
//@ [chk_fail_ret] compile-flags: -Zcontract-checks=yes
//@ [chk_fail_yeet] compile-flags: -Zcontract-checks=yes
//! This test ensures that ensures clauses are checked for different return points of a function.
#![feature(contracts)]
//~^ WARN the feature `contracts` is incomplete and may not be safe to use and/or cause compiler crashes [incomplete_features]
#![feature(yeet_expr)]
/// This ensures will fail in different return points depending on the input.
#[core::contracts::ensures(|ret: &Option<u32>| ret.is_some())]
fn try_sum(x: u32, y: u32, z: u32) -> Option<u32> {
// Use Yeet to return early.
if x == u32::MAX && (y > 0 || z > 0) { do yeet }
// Use `?` to early return.
let partial = x.checked_add(y)?;
// Explicitly use `return` clause.
if u32::MAX - partial < z {
return None;
}
Some(partial + z)
}
fn main() {
// This should always succeed
assert_eq!(try_sum(0, 1, 2), Some(3));
#[cfg(any(unchk_pass, chk_fail_yeet))]
assert_eq!(try_sum(u32::MAX, 1, 1), None);
#[cfg(any(unchk_pass, chk_fail_try))]
assert_eq!(try_sum(u32::MAX - 10, 12, 0), None);
#[cfg(any(unchk_pass, chk_fail_ret))]
assert_eq!(try_sum(u32::MAX - 10, 2, 100), None);
}
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