This reverts commit 1eeb8e8b15, reversing
changes made to 324bf2b9fd.
Unfortunately the assert desugaring change is not backwards compatible,
see RUST-145770.
Code such as
```rust
#[derive(Debug)]
struct F {
data: bool
}
impl std::ops::Not for F {
type Output = bool;
fn not(self) -> Self::Output { !self.data }
}
fn main() {
let f = F { data: true };
assert!(f);
}
```
would be broken by the assert desugaring change. We may need to land
the change over an edition boundary, or limit the editions that the
desugaring change impacts.
In the desugaring of `assert!`, we now expand to a `match` expression
instead of `if !cond {..}`.
The span of incorrect conditions will point only at the expression, and not
the whole `assert!` invocation.
```
error[E0308]: mismatched types
--> $DIR/issue-14091.rs:2:13
|
LL | assert!(1,1);
| ^ expected `bool`, found integer
```
We no longer mention the expression needing to implement the `Not` trait.
```
error[E0308]: mismatched types
--> $DIR/issue-14091-2.rs:15:13
|
LL | assert!(x, x);
| ^ expected `bool`, found `BytePos`
```
`assert!(val)` now desugars to:
```rust
match val {
true => {},
_ => $crate::panic::panic_2021!(),
}
```
Fix#122159.
We make some minor changes to some diagnostics to avoid span overlap on
type mismatch or inverted "expected"/"found" on type errors.
We remove some unnecessary parens from core, alloc and miri.
address review comments
