"Implement default member" assist on trait messes up on pattern #20215
Description
rust-analyzer version: 0.3.2533-standalone
rustc version: rustc 1.88.0 (6b00bc388 2025-06-23)
editor or extension: Code OSS (like vscode)
relevant settings: None
code snippet to reproduce:
struct MyRange;
impl core::ops::RangeBounds<usize> for MyRange {
fn start_bound(&self) -> core::ops::Bound<&usize> {
todo!()
}
fn end_bound(&self) -> core::ops::Bound<&usize> {
todo!()
}
}Click on impl and use the "Implement default member" assist.
The resulting code looks like this:
struct MyRange;
impl core::ops::RangeBounds<usize> for MyRange {
fn start_bound(&self) -> core::ops::Bound<&usize> {
todo!()
}
fn end_bound(&self) -> core::ops::Bound<&usize> {
todo!()
}
fn contains<U>(&self, item: &U) -> bool
where
usize: PartialOrd<U>,
U: ?Sized + PartialOrd<usize>,
{
(match self.start_bound() {
std::ops::Bound::Included(start) => start <= item,
std::ops::Bound::Excluded(start) => start < item,
Unbounded => true,
}) && (match self.end_bound() {
std::ops::Bound::Included(end) => item <= end,
std::ops::Bound::Excluded(end) => item < end,
Unbounded => true,
})
}
fn is_empty(&self) -> bool
where
usize: PartialOrd,
{
!match (self.start_bound(), self.end_bound()) {
(Unbounded, _) | (_, Unbounded) => true,
(std::ops::Bound::Included(start), std::ops::Bound::Excluded(end))
| (std::ops::Bound::Excluded(start), std::ops::Bound::Included(end))
| (std::ops::Bound::Excluded(start), std::ops::Bound::Excluded(end)) => start < end,
(std::ops::Bound::Included(start), std::ops::Bound::Included(end)) => start <= end,
}
}
}This fails to compile because is_empty is unstable and because the lint bindings_with_variant_name is deny by default, it triggers on Unbounded which should be std::ops::Bound::Unbounded.