Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 119 insertions, 0 deletions

diff --git a/vendor/chalk-solve-0.87.0/src/clauses/builtin_traits.rs b/vendor/chalk-solve-0.87.0/src/clauses/builtin_traits.rs
new file mode 100644
index 000000000..b5a1c7d57
--- /dev/null
+++ b/vendor/chalk-solve-0.87.0/src/clauses/builtin_traits.rs
@@ -0,0 +1,119 @@
+use super::{builder::ClauseBuilder, generalize};
+use crate::{CanonicalVarKinds, Interner, RustIrDatabase, TraitRef, WellKnownTrait};
+use chalk_ir::{Floundered, Substitution, Ty};
+
+mod clone;
+mod copy;
+mod discriminant_kind;
+mod fn_family;
+mod generator;
+mod sized;
+mod tuple;
+mod unsize;
+
+/// For well known traits we have special hard-coded impls, either as an
+/// optimization or to enforce special rules for correctness.
+pub fn add_builtin_program_clauses<I: Interner>(
+    db: &dyn RustIrDatabase<I>,
+    builder: &mut ClauseBuilder<'_, I>,
+    well_known: WellKnownTrait,
+    trait_ref: TraitRef<I>,
+    binders: &CanonicalVarKinds<I>,
+) -> Result<(), Floundered> {
+    // If `trait_ref` contains bound vars, we want to universally quantify them.
+    // `Generalize` collects them for us.
+    let generalized = generalize::Generalize::apply(db.interner(), trait_ref);
+
+    builder.push_binders(generalized, |builder, trait_ref| {
+        let self_ty = trait_ref.self_type_parameter(db.interner());
+        let ty = self_ty.kind(db.interner()).clone();
+
+        match well_known {
+            // Built-in traits are non-enumerable.
+            _ if self_ty.is_general_var(db.interner(), binders) => return Err(Floundered),
+            WellKnownTrait::Sized => {
+                sized::add_sized_program_clauses(db, builder, trait_ref, ty, binders)?;
+            }
+            WellKnownTrait::Copy => {
+                copy::add_copy_program_clauses(db, builder, trait_ref, ty, binders)?;
+            }
+            WellKnownTrait::Clone => {
+                clone::add_clone_program_clauses(db, builder, trait_ref, ty, binders)?;
+            }
+            WellKnownTrait::FnOnce | WellKnownTrait::FnMut | WellKnownTrait::Fn => {
+                fn_family::add_fn_trait_program_clauses(db, builder, well_known, self_ty);
+            }
+            WellKnownTrait::Unsize => {
+                unsize::add_unsize_program_clauses(db, builder, trait_ref, ty)
+            }
+            // DiscriminantKind is automatically implemented for all types
+            WellKnownTrait::DiscriminantKind => builder.push_fact(trait_ref),
+            WellKnownTrait::Generator => {
+                generator::add_generator_program_clauses(db, builder, self_ty)?;
+            }
+            WellKnownTrait::Tuple => {
+                tuple::add_tuple_program_clauses(db, builder, self_ty)?;
+            }
+            // There are no builtin impls provided for the following traits:
+            WellKnownTrait::Unpin
+            | WellKnownTrait::Drop
+            | WellKnownTrait::CoerceUnsized
+            | WellKnownTrait::DispatchFromDyn => (),
+        }
+        Ok(())
+    })
+}
+
+/// Like `add_builtin_program_clauses`, but for `DomainGoal::Normalize` involving
+/// a projection (e.g. `<fn(u8) as FnOnce<(u8,)>>::Output`)
+pub fn add_builtin_assoc_program_clauses<I: Interner>(
+    db: &dyn RustIrDatabase<I>,
+    builder: &mut ClauseBuilder<'_, I>,
+    well_known: WellKnownTrait,
+    self_ty: Ty<I>,
+) -> Result<(), Floundered> {
+    match well_known {
+        WellKnownTrait::FnOnce => {
+            // If `self_ty` contains bound vars, we want to universally quantify them.
+            // `Generalize` collects them for us.
+            let generalized = generalize::Generalize::apply(db.interner(), self_ty);
+
+            builder.push_binders(generalized, |builder, self_ty| {
+                fn_family::add_fn_trait_program_clauses(db, builder, well_known, self_ty);
+                Ok(())
+            })
+        }
+        WellKnownTrait::DiscriminantKind => {
+            discriminant_kind::add_discriminant_clauses(db, builder, self_ty)
+        }
+        WellKnownTrait::Generator => {
+            let generalized = generalize::Generalize::apply(db.interner(), self_ty);
+
+            builder.push_binders(generalized, |builder, self_ty| {
+                generator::add_generator_program_clauses(db, builder, self_ty)
+            })
+        }
+        _ => Ok(()),
+    }
+}
+
+/// Given a trait ref `T0: Trait` and a list of types `U0..Un`, pushes a clause of the form
+/// `Implemented(T0: Trait) :- Implemented(U0: Trait) .. Implemented(Un: Trait)`
+pub fn needs_impl_for_tys<I: Interner>(
+    db: &dyn RustIrDatabase<I>,
+    builder: &mut ClauseBuilder<'_, I>,
+    trait_ref: TraitRef<I>,
+    tys: impl Iterator<Item = Ty<I>>,
+) {
+    let trait_id = trait_ref.trait_id;
+
+    // The trait must take one parameter (a type)
+    debug_assert_eq!(db.trait_datum(trait_id).binders.len(db.interner()), 1,);
+    builder.push_clause(
+        trait_ref,
+        tys.map(|ty| TraitRef {
+            trait_id,
+            substitution: Substitution::from1(db.interner(), ty),
+        }),
+    );
+}