Auto merge of #18205 - noahmbright:object_safety, r=HKalbasi

Rename object_safety

First PR here (yay!), so I read some of the getting started docs. There are a couple references to `handlers.rs`, which as far as I can tell has been refactored into `handlers/*.rs`. I made some tweaks to that in one commit. There is one fixme about a function called `to_lsp_runnable`, which I can't find anywhere at all. I can update that if I get some more info there.

Otherwise I changed references to object safety, is object safe, etc., trying to match case/style as I went. There was one case I found where there's a trait from somewhere else called `is_object_safe`, which I found defined in my cargo registry. I didn't touch that for now, just marked it with a fixme

crates/hir-ty/src/chalk_db.rs

@@ -382,8 +382,9 @@ impl chalk_solve::RustIrDatabase<Interner> for ChalkContext<'_> {
     }
 
     fn is_object_safe(&self, trait_id: chalk_ir::TraitId<Interner>) -> bool {
+        // FIXME: When cargo is updated, change to dyn_compatibility
         let trait_ = from_chalk_trait_id(trait_id);
-        crate::object_safety::object_safety(self.db, trait_).is_none()
+        crate::dyn_compatibility::dyn_compatibility(self.db, trait_).is_none()
     }
 
     fn closure_kind(

crates/hir-ty/src/db.rs

@@ -20,11 +20,11 @@ use triomphe::Arc;
 use crate::{
     chalk_db,
     consteval::ConstEvalError,
+    dyn_compatibility::DynCompatibilityViolation,
     layout::{Layout, LayoutError},
     lower::{GenericDefaults, GenericPredicates},
     method_resolution::{InherentImpls, TraitImpls, TyFingerprint},
     mir::{BorrowckResult, MirBody, MirLowerError},
-    object_safety::ObjectSafetyViolation,
     Binders, ClosureId, Const, FnDefId, ImplTraitId, ImplTraits, InferenceResult, Interner,
     PolyFnSig, Substitution, TraitEnvironment, TraitRef, Ty, TyDefId, ValueTyDefId,
 };
@@ -108,8 +108,8 @@ pub trait HirDatabase: DefDatabase + Upcast<dyn DefDatabase> {
     #[salsa::invoke(crate::layout::target_data_layout_query)]
     fn target_data_layout(&self, krate: CrateId) -> Result<Arc<TargetDataLayout>, Arc<str>>;
 
-    #[salsa::invoke(crate::object_safety::object_safety_of_trait_query)]
-    fn object_safety_of_trait(&self, trait_: TraitId) -> Option<ObjectSafetyViolation>;
+    #[salsa::invoke(crate::dyn_compatibility::dyn_compatibility_of_trait_query)]
+    fn dyn_compatibility_of_trait(&self, trait_: TraitId) -> Option<DynCompatibilityViolation>;
 
     #[salsa::invoke(crate::lower::ty_query)]
     #[salsa::cycle(crate::lower::ty_recover)]
@@ -280,8 +280,8 @@ pub trait HirDatabase: DefDatabase + Upcast<dyn DefDatabase> {
 }
 
 #[test]
-fn hir_database_is_object_safe() {
-    fn _assert_object_safe(_: &dyn HirDatabase) {}
+fn hir_database_is_dyn_compatible() {
+    fn _assert_dyn_compatible(_: &dyn HirDatabase) {}
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]

crates/hir-ty/src/object_safety.rs → crates/hir-ty/src/dyn_compatibility.rs

@@ -1,4 +1,4 @@
-//! Compute the object-safety of a trait
+//! Compute the dyn-compatibility of a trait
 
 use std::ops::ControlFlow;
 
@@ -28,14 +28,14 @@ use crate::{
 };
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub enum ObjectSafetyViolation {
+pub enum DynCompatibilityViolation {
     SizedSelf,
     SelfReferential,
     Method(FunctionId, MethodViolationCode),
     AssocConst(ConstId),
     GAT(TypeAliasId),
     // This doesn't exist in rustc, but added for better visualization
-    HasNonSafeSuperTrait(TraitId),
+    HasNonCompatibleSuperTrait(TraitId),
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -50,70 +50,73 @@ pub enum MethodViolationCode {
     UndispatchableReceiver,
 }
 
-pub fn object_safety(db: &dyn HirDatabase, trait_: TraitId) -> Option<ObjectSafetyViolation> {
+pub fn dyn_compatibility(
+    db: &dyn HirDatabase,
+    trait_: TraitId,
+) -> Option<DynCompatibilityViolation> {
     for super_trait in all_super_traits(db.upcast(), trait_).into_iter().skip(1).rev() {
-        if db.object_safety_of_trait(super_trait).is_some() {
-            return Some(ObjectSafetyViolation::HasNonSafeSuperTrait(super_trait));
+        if db.dyn_compatibility_of_trait(super_trait).is_some() {
+            return Some(DynCompatibilityViolation::HasNonCompatibleSuperTrait(super_trait));
         }
     }
 
-    db.object_safety_of_trait(trait_)
+    db.dyn_compatibility_of_trait(trait_)
 }
 
-pub fn object_safety_with_callback<F>(
+pub fn dyn_compatibility_with_callback<F>(
     db: &dyn HirDatabase,
     trait_: TraitId,
     cb: &mut F,
 ) -> ControlFlow<()>
 where
-    F: FnMut(ObjectSafetyViolation) -> ControlFlow<()>,
+    F: FnMut(DynCompatibilityViolation) -> ControlFlow<()>,
 {
     for super_trait in all_super_traits(db.upcast(), trait_).into_iter().skip(1).rev() {
-        if db.object_safety_of_trait(super_trait).is_some() {
-            cb(ObjectSafetyViolation::HasNonSafeSuperTrait(trait_))?;
+        if db.dyn_compatibility_of_trait(super_trait).is_some() {
+            cb(DynCompatibilityViolation::HasNonCompatibleSuperTrait(trait_))?;
         }
     }
 
-    object_safety_of_trait_with_callback(db, trait_, cb)
+    dyn_compatibility_of_trait_with_callback(db, trait_, cb)
 }
 
-pub fn object_safety_of_trait_with_callback<F>(
+pub fn dyn_compatibility_of_trait_with_callback<F>(
     db: &dyn HirDatabase,
     trait_: TraitId,
     cb: &mut F,
 ) -> ControlFlow<()>
 where
-    F: FnMut(ObjectSafetyViolation) -> ControlFlow<()>,
+    F: FnMut(DynCompatibilityViolation) -> ControlFlow<()>,
 {
     // Check whether this has a `Sized` bound
     if generics_require_sized_self(db, trait_.into()) {
-        cb(ObjectSafetyViolation::SizedSelf)?;
+        cb(DynCompatibilityViolation::SizedSelf)?;
     }
 
     // Check if there exist bounds that referencing self
     if predicates_reference_self(db, trait_) {
-        cb(ObjectSafetyViolation::SelfReferential)?;
+        cb(DynCompatibilityViolation::SelfReferential)?;
     }
     if bounds_reference_self(db, trait_) {
-        cb(ObjectSafetyViolation::SelfReferential)?;
+        cb(DynCompatibilityViolation::SelfReferential)?;
     }
 
     // rustc checks for non-lifetime binders here, but we don't support HRTB yet
 
     let trait_data = db.trait_data(trait_);
     for (_, assoc_item) in &trait_data.items {
-        object_safety_violation_for_assoc_item(db, trait_, *assoc_item, cb)?;
+        dyn_compatibility_violation_for_assoc_item(db, trait_, *assoc_item, cb)?;
     }
 
     ControlFlow::Continue(())
 }
 
-pub fn object_safety_of_trait_query(
+pub fn dyn_compatibility_of_trait_query(
     db: &dyn HirDatabase,
     trait_: TraitId,
-) -> Option<ObjectSafetyViolation> {
+) -> Option<DynCompatibilityViolation> {
     let mut res = None;
-    object_safety_of_trait_with_callback(db, trait_, &mut |osv| {
+    dyn_compatibility_of_trait_with_callback(db, trait_, &mut |osv| {
         res = Some(osv);
         ControlFlow::Break(())
     });
@@ -321,14 +324,14 @@ fn contains_illegal_self_type_reference<T: TypeVisitable<Interner>>(
     t.visit_with(visitor.as_dyn(), outer_binder).is_break()
 }
 
-fn object_safety_violation_for_assoc_item<F>(
+fn dyn_compatibility_violation_for_assoc_item<F>(
     db: &dyn HirDatabase,
     trait_: TraitId,
     item: AssocItemId,
     cb: &mut F,
 ) -> ControlFlow<()>
 where
-    F: FnMut(ObjectSafetyViolation) -> ControlFlow<()>,
+    F: FnMut(DynCompatibilityViolation) -> ControlFlow<()>,
 {
     // Any item that has a `Self : Sized` requisite is otherwise
     // exempt from the regulations.
@@ -337,10 +340,10 @@ where
     }
 
     match item {
-        AssocItemId::ConstId(it) => cb(ObjectSafetyViolation::AssocConst(it)),
+        AssocItemId::ConstId(it) => cb(DynCompatibilityViolation::AssocConst(it)),
         AssocItemId::FunctionId(it) => {
             virtual_call_violations_for_method(db, trait_, it, &mut |mvc| {
-                cb(ObjectSafetyViolation::Method(it, mvc))
+                cb(DynCompatibilityViolation::Method(it, mvc))
             })
         }
         AssocItemId::TypeAliasId(it) => {
@@ -350,7 +353,7 @@ where
             } else {
                 let generic_params = db.generic_params(item.into());
                 if !generic_params.is_empty() {
-                    cb(ObjectSafetyViolation::GAT(it))
+                    cb(DynCompatibilityViolation::GAT(it))
                 } else {
                     ControlFlow::Continue(())
                 }
@@ -469,7 +472,7 @@ fn receiver_is_dispatchable(
         return false;
     };
 
-    // `self: Self` can't be dispatched on, but this is already considered object safe.
+    // `self: Self` can't be dispatched on, but this is already considered dyn compatible
     // See rustc's comment on https://github.com/rust-lang/rust/blob/3f121b9461cce02a703a0e7e450568849dfaa074/compiler/rustc_trait_selection/src/traits/object_safety.rs#L433-L437
     if sig
         .skip_binders()