Unnamed repository; edit this file 'description' to name the repository.
| -rw-r--r-- | crates/hir-ty/src/lower.rs | 9 | ||||
| -rw-r--r-- | crates/hir-ty/src/tests/regression.rs | 21 | ||||
| -rw-r--r-- | crates/hir-ty/src/utils.rs | 18 |
3 files changed, 39 insertions, 9 deletions
diff --git a/crates/hir-ty/src/lower.rs b/crates/hir-ty/src/lower.rs index 239f66bcb7..3ec321ad37 100644 --- a/crates/hir-ty/src/lower.rs +++ b/crates/hir-ty/src/lower.rs @@ -509,7 +509,14 @@ impl<'a> TyLoweringContext<'a> { TyKind::Placeholder(to_placeholder_idx(self.db, param_id.into())) } ParamLoweringMode::Variable => { - let idx = generics.param_idx(param_id.into()).expect("matching generics"); + let idx = match generics.param_idx(param_id.into()) { + None => { + never!("no matching generics"); + return (TyKind::Error.intern(Interner), None); + } + Some(idx) => idx, + }; + TyKind::BoundVar(BoundVar::new(self.in_binders, idx)) } } diff --git a/crates/hir-ty/src/tests/regression.rs b/crates/hir-ty/src/tests/regression.rs index 93a88ab58e..9b64fccccd 100644 --- a/crates/hir-ty/src/tests/regression.rs +++ b/crates/hir-ty/src/tests/regression.rs @@ -1527,6 +1527,27 @@ unsafe impl Storage for InlineStorage { } #[test] +fn gat_crash_3() { + cov_mark::check!(ignore_gats); + check_no_mismatches( + r#" +trait Collection { + type Item; + type Member<T>: Collection<Item = T>; + fn add(&mut self, value: Self::Item) -> Result<(), Self::Error>; +} +struct ConstGen<T, const N: usize> { + data: [T; N], +} +impl<T, const N: usize> Collection for ConstGen<T, N> { + type Item = T; + type Member<U> = ConstGen<U, N>; +} + "#, + ); +} + +#[test] fn cfgd_out_self_param() { cov_mark::check!(cfgd_out_self_param); check_no_mismatches( diff --git a/crates/hir-ty/src/utils.rs b/crates/hir-ty/src/utils.rs index 83319755da..bdb9ade9c8 100644 --- a/crates/hir-ty/src/utils.rs +++ b/crates/hir-ty/src/utils.rs @@ -176,10 +176,16 @@ pub(crate) fn generics(db: &dyn DefDatabase, def: GenericDefId) -> Generics { let parent_generics = parent_generic_def(db, def).map(|def| Box::new(generics(db, def))); if parent_generics.is_some() && matches!(def, GenericDefId::TypeAliasId(_)) { let params = db.generic_params(def); + let parent_params = &parent_generics.as_ref().unwrap().params; let has_consts = params.iter().any(|(_, x)| matches!(x, TypeOrConstParamData::ConstParamData(_))); - return if has_consts { - // XXX: treat const generic associated types as not existing to avoid crashes (#11769) + let parent_has_consts = + parent_params.iter().any(|(_, x)| matches!(x, TypeOrConstParamData::ConstParamData(_))); + return if has_consts || parent_has_consts { + // XXX: treat const generic associated types as not existing to avoid crashes + // (#11769, #12193) + // Note: also crashes when the parent has const generics (also even if the GAT + // doesn't use them), see `tests::regression::gat_crash_3` for an example. // // Chalk expects the inner associated type's parameters to come // *before*, not after the trait's generics as we've always done it. @@ -264,12 +270,8 @@ impl Generics { fn find_param(&self, param: TypeOrConstParamId) -> Option<(usize, &TypeOrConstParamData)> { if param.parent == self.def { - let (idx, (_local_id, data)) = self - .params - .iter() - .enumerate() - .find(|(_, (idx, _))| *idx == param.local_id) - .unwrap(); + let (idx, (_local_id, data)) = + self.params.iter().enumerate().find(|(_, (idx, _))| *idx == param.local_id)?; let parent_len = self.parent_generics().map_or(0, Generics::len); Some((parent_len + idx, data)) } else { |