bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/infer/unify.rs')
-rw-r--r--crates/hir-ty/src/infer/unify.rs118
1 files changed, 62 insertions, 56 deletions
diff --git a/crates/hir-ty/src/infer/unify.rs b/crates/hir-ty/src/infer/unify.rs
index 54aa18ce20..165861c1b1 100644
--- a/crates/hir-ty/src/infer/unify.rs
+++ b/crates/hir-ty/src/infer/unify.rs
@@ -666,7 +666,7 @@ impl<'a> InferenceTable<'a> {
highest_known_var: InferenceVar,
}
impl TypeFolder<Interner> for VarFudger<'_, '_> {
- fn as_dyn(&mut self) -> &mut dyn TypeFolder<Interner, Error = Self::Error> {
+ fn as_dyn(&mut self) -> &mut dyn TypeFolder<Interner> {
self
}
@@ -794,69 +794,75 @@ impl<'a> InferenceTable<'a> {
ty: &Ty,
num_args: usize,
) -> Option<(FnTrait, Vec<Ty>, Ty)> {
- let krate = self.trait_env.krate;
- let fn_once_trait = FnTrait::FnOnce.get_id(self.db, krate)?;
- let trait_data = self.db.trait_data(fn_once_trait);
- let output_assoc_type =
- trait_data.associated_type_by_name(&Name::new_symbol_root(sym::Output.clone()))?;
-
- let mut arg_tys = Vec::with_capacity(num_args);
- let arg_ty = TyBuilder::tuple(num_args)
- .fill(|it| {
- let arg = match it {
- ParamKind::Type => self.new_type_var(),
- ParamKind::Lifetime => unreachable!("Tuple with lifetime parameter"),
- ParamKind::Const(_) => unreachable!("Tuple with const parameter"),
- };
- arg_tys.push(arg.clone());
- arg.cast(Interner)
- })
- .build();
-
- let b = TyBuilder::trait_ref(self.db, fn_once_trait);
- if b.remaining() != 2 {
- return None;
- }
- let mut trait_ref = b.push(ty.clone()).push(arg_ty).build();
+ for (fn_trait_name, output_assoc_name, subtraits) in [
+ (FnTrait::FnOnce, sym::Output.clone(), &[FnTrait::Fn, FnTrait::FnMut][..]),
+ (FnTrait::AsyncFnMut, sym::CallRefFuture.clone(), &[FnTrait::AsyncFn]),
+ (FnTrait::AsyncFnOnce, sym::CallOnceFuture.clone(), &[]),
+ ] {
+ let krate = self.trait_env.krate;
+ let fn_trait = fn_trait_name.get_id(self.db, krate)?;
+ let trait_data = self.db.trait_data(fn_trait);
+ let output_assoc_type =
+ trait_data.associated_type_by_name(&Name::new_symbol_root(output_assoc_name))?;
+
+ let mut arg_tys = Vec::with_capacity(num_args);
+ let arg_ty = TyBuilder::tuple(num_args)
+ .fill(|it| {
+ let arg = match it {
+ ParamKind::Type => self.new_type_var(),
+ ParamKind::Lifetime => unreachable!("Tuple with lifetime parameter"),
+ ParamKind::Const(_) => unreachable!("Tuple with const parameter"),
+ };
+ arg_tys.push(arg.clone());
+ arg.cast(Interner)
+ })
+ .build();
+
+ let b = TyBuilder::trait_ref(self.db, fn_trait);
+ if b.remaining() != 2 {
+ return None;
+ }
+ let mut trait_ref = b.push(ty.clone()).push(arg_ty).build();
- let projection = {
- TyBuilder::assoc_type_projection(
+ let projection = TyBuilder::assoc_type_projection(
self.db,
output_assoc_type,
Some(trait_ref.substitution.clone()),
)
- .build()
- };
+ .fill_with_unknown()
+ .build();
- let trait_env = self.trait_env.env.clone();
- let obligation = InEnvironment {
- goal: trait_ref.clone().cast(Interner),
- environment: trait_env.clone(),
- };
- let canonical = self.canonicalize(obligation.clone());
- if self.db.trait_solve(krate, self.trait_env.block, canonical.cast(Interner)).is_some() {
- self.register_obligation(obligation.goal);
- let return_ty = self.normalize_projection_ty(projection);
- for fn_x in [FnTrait::Fn, FnTrait::FnMut, FnTrait::FnOnce] {
- let fn_x_trait = fn_x.get_id(self.db, krate)?;
- trait_ref.trait_id = to_chalk_trait_id(fn_x_trait);
- let obligation: chalk_ir::InEnvironment<chalk_ir::Goal<Interner>> = InEnvironment {
- goal: trait_ref.clone().cast(Interner),
- environment: trait_env.clone(),
- };
- let canonical = self.canonicalize(obligation.clone());
- if self
- .db
- .trait_solve(krate, self.trait_env.block, canonical.cast(Interner))
- .is_some()
- {
- return Some((fn_x, arg_tys, return_ty));
+ let trait_env = self.trait_env.env.clone();
+ let obligation = InEnvironment {
+ goal: trait_ref.clone().cast(Interner),
+ environment: trait_env.clone(),
+ };
+ let canonical = self.canonicalize(obligation.clone());
+ if self.db.trait_solve(krate, self.trait_env.block, canonical.cast(Interner)).is_some()
+ {
+ self.register_obligation(obligation.goal);
+ let return_ty = self.normalize_projection_ty(projection);
+ for &fn_x in subtraits {
+ let fn_x_trait = fn_x.get_id(self.db, krate)?;
+ trait_ref.trait_id = to_chalk_trait_id(fn_x_trait);
+ let obligation: chalk_ir::InEnvironment<chalk_ir::Goal<Interner>> =
+ InEnvironment {
+ goal: trait_ref.clone().cast(Interner),
+ environment: trait_env.clone(),
+ };
+ let canonical = self.canonicalize(obligation.clone());
+ if self
+ .db
+ .trait_solve(krate, self.trait_env.block, canonical.cast(Interner))
+ .is_some()
+ {
+ return Some((fn_x, arg_tys, return_ty));
+ }
}
+ return Some((fn_trait_name, arg_tys, return_ty));
}
- unreachable!("It should at least implement FnOnce at this point");
- } else {
- None
}
+ None
}
pub(super) fn insert_type_vars<T>(&mut self, ty: T) -> T
@@ -1004,7 +1010,7 @@ mod resolve {
where
F: Fn(InferenceVar, VariableKind, GenericArg, DebruijnIndex) -> GenericArg,
{
- fn as_dyn(&mut self) -> &mut dyn TypeFolder<Interner, Error = Self::Error> {
+ fn as_dyn(&mut self) -> &mut dyn TypeFolder<Interner> {
self
}