Handle impl-trait-in-assoc-types separately from type-alias-impl-trait

rust-lang · Mar 1, 2024 · 73090ab · 73090ab
1 parent d08b223
commit 73090ab
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Showing 14 changed files with 66 additions and 64 deletions.
diff --git a/compiler/rustc_infer/src/infer/opaque_types.rs b/compiler/rustc_infer/src/infer/opaque_types.rs
@@ -106,7 +106,7 @@ impl<'tcx> InferCtxt<'tcx> {
             ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) if def_id.is_local() => {
                 let def_id = def_id.expect_local();
                 match self.defining_use_anchor {
-                    DefiningAnchor::Bind(_) => {
+                    DefiningAnchor::Bind { .. } => {
                         // Check that this is `impl Trait` type is
                         // declared by `parent_def_id` -- i.e., one whose
                         // value we are inferring. At present, this is
@@ -373,14 +373,16 @@ impl<'tcx> InferCtxt<'tcx> {
     /// in its defining scope.
     #[instrument(skip(self), level = "trace", ret)]
     pub fn opaque_type_origin(&self, def_id: LocalDefId) -> Option<OpaqueTyOrigin> {
-        let defined_opaque_types = match self.defining_use_anchor {
+        let (rpit_and_tait, in_assoc_types) = match self.defining_use_anchor {
             DefiningAnchor::Bubble | DefiningAnchor::Error => return None,
-            DefiningAnchor::Bind(bind) => bind,
+            DefiningAnchor::Bind { rpit_and_tait, in_assoc_types } => {
+                (rpit_and_tait, in_assoc_types)
+            }
         };
 
         let origin = self.tcx.opaque_type_origin(def_id);
 
-        defined_opaque_types.contains(&def_id).then_some(origin)
+        (rpit_and_tait.contains(&def_id) || in_assoc_types.contains(&def_id)).then_some(origin)
     }
 }
 

diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs
@@ -15,6 +15,7 @@ use crate::ty::abstract_const::NotConstEvaluatable;
 use crate::ty::{self, AdtKind, Ty};
 use crate::ty::{GenericArgsRef, TyCtxt};
 
+use hir::def::DefKind;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{Applicability, Diag, EmissionGuarantee};
 use rustc_hir as hir;
@@ -1004,7 +1005,7 @@ pub enum CodegenObligationError {
 pub enum DefiningAnchor<'tcx> {
     /// Define opaques which are in-scope of the current item being analyzed.
     /// Also, eagerly replace these opaque types in `replace_opaque_types_with_inference_vars`.
-    Bind(&'tcx [LocalDefId]),
+    Bind { rpit_and_tait: &'tcx [LocalDefId], in_assoc_types: &'tcx [LocalDefId] },
     /// In contexts where we don't currently know what opaques are allowed to be
     /// defined, such as (old solver) canonical queries, we will simply allow
     /// opaques to be defined, but "bubble" them up in the canonical response or
@@ -1021,6 +1022,19 @@ pub enum DefiningAnchor<'tcx> {
 
 impl<'tcx> DefiningAnchor<'tcx> {
     pub fn bind(tcx: TyCtxt<'tcx>, item: LocalDefId) -> Self {
-        Self::Bind(tcx.opaque_types_defined_by(item))
+        Self::Bind {
+            rpit_and_tait: tcx.opaque_types_defined_by(item),
+            in_assoc_types: match tcx.def_kind(item) {
+                DefKind::AssocFn | DefKind::AssocConst | DefKind::AssocTy => {
+                    let parent = tcx.local_parent(item);
+                    if matches!(tcx.def_kind(parent), DefKind::Impl { of_trait: true }) {
+                        tcx.impl_trait_in_assoc_types_defined_by(item)
+                    } else {
+                        &[]
+                    }
+                }
+                _ => &[],
+            },
+        }
     }
 }
diff --git a/compiler/rustc_ty_utils/src/opaque_types.rs b/compiler/rustc_ty_utils/src/opaque_types.rs
@@ -205,7 +205,19 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for OpaqueTypeCollector<'tcx> {
         t.super_visit_with(self)?;
         match t.kind() {
             ty::Alias(ty::Opaque, alias_ty) if alias_ty.def_id.is_local() => {
-                self.visit_opaque_ty(alias_ty);
+                let mut parent = alias_ty.def_id.expect_local();
+                // Only collect opaque types that are not impl trait in associated types
+                loop {
+                    match self.tcx.def_kind(parent) {
+                        DefKind::OpaqueTy => {}
+                        DefKind::AssocTy => break,
+                        _ => {
+                            self.visit_opaque_ty(alias_ty);
+                            break;
+                        }
+                    }
+                    parent = self.tcx.local_parent(parent);
+                }
             }
             // Skips type aliases, as they are meant to be transparent.
             ty::Alias(ty::Weak, alias_ty) if alias_ty.def_id.is_local() => {
@@ -363,7 +375,7 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for ImplTraitInAssocTypeCollector<'tcx> {
                                 .instantiate(self.0.tcx, impl_args)
                                 .visit_with(self);
                         } else {
-                            self.0.tcx.dcx().span_bug(
+                            self.0.tcx.dcx().span_delayed_bug(
                                 self.0.tcx.def_span(assoc.def_id),
                                 "item had incorrect args",
                             );

diff --git a/tests/ui/generic-associated-types/issue-88595.rs b/tests/ui/generic-associated-types/issue-88595.rs
@@ -20,5 +20,4 @@ impl<'a> A<'a> for C {
 
     fn a(&'a self) -> Self::B<'a> {} //~ ERROR: non-defining opaque type use in defining scope
     //~^ ERROR: non-defining opaque type use in defining scope
-    //~| ERROR: non-defining opaque type use in defining scope
 }
diff --git a/tests/ui/generic-associated-types/issue-88595.stderr b/tests/ui/generic-associated-types/issue-88595.stderr
@@ -10,19 +10,6 @@ note: for this opaque type
 LL |     type B<'b> = impl Clone;
    |                  ^^^^^^^^^^
 
-error: non-defining opaque type use in defining scope
-  --> $DIR/issue-88595.rs:21:23
-   |
-LL |     fn a(&'a self) -> Self::B<'a> {}
-   |                       ^^^^^^^^^^^ generic argument `'a` used twice
-   |
-note: for this opaque type
-  --> $DIR/issue-88595.rs:19:18
-   |
-LL |     type B<'b> = impl Clone;
-   |                  ^^^^^^^^^^
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
 error: non-defining opaque type use in defining scope
   --> $DIR/issue-88595.rs:21:35
    |
@@ -37,5 +24,5 @@ LL | impl<'a> A<'a> for C {
 LL |     type B<'b> = impl Clone;
    |            ^^
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
diff --git a/tests/ui/type-alias-impl-trait/hidden_behind_struct_field2.rs b/tests/ui/type-alias-impl-trait/hidden_behind_struct_field2.rs
@@ -15,7 +15,7 @@ impl Trait for Bar {
     type Assoc = impl std::fmt::Debug;
     fn foo() -> Foo {
         Foo { field: () }
-        //~^ ERROR: item constrains opaque type that is not in its signature
+        //~^ ERROR: mismatched types
     }
 }
 

diff --git a/tests/ui/type-alias-impl-trait/hidden_behind_struct_field2.stderr b/tests/ui/type-alias-impl-trait/hidden_behind_struct_field2.stderr
@@ -1,15 +1,20 @@
-error: item constrains opaque type that is not in its signature
+error[E0308]: mismatched types
   --> $DIR/hidden_behind_struct_field2.rs:17:22
    |
+LL |     type Assoc = impl std::fmt::Debug;
+   |                  -------------------- the expected opaque type
+LL |     fn foo() -> Foo {
 LL |         Foo { field: () }
-   |                      ^^
+   |                      ^^ expected opaque type, found `()`
    |
-   = note: this item must mention the opaque type in its signature in order to be able to register hidden types
-note: this item must mention the opaque type in its signature in order to be able to register hidden types
+   = note: expected opaque type `<Bar as Trait>::Assoc`
+                found unit type `()`
+note: this item must have the opaque type in its signature in order to be able to register hidden types
   --> $DIR/hidden_behind_struct_field2.rs:16:8
    |
 LL |     fn foo() -> Foo {
    |        ^^^
 
 error: aborting due to 1 previous error
 
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/type-alias-impl-trait/hidden_behind_struct_field3.rs b/tests/ui/type-alias-impl-trait/hidden_behind_struct_field3.rs
@@ -17,7 +17,7 @@ impl Trait for Bar {
     type Assoc = impl Iterator<Item = Foo>;
     fn foo() -> Self::Assoc {
         vec![Foo { field: () }].into_iter()
-        //~^ ERROR item constrains opaque type that is not in its signature
+        //~^ ERROR mismatched types
     }
 }
 

diff --git a/tests/ui/type-alias-impl-trait/hidden_behind_struct_field3.stderr b/tests/ui/type-alias-impl-trait/hidden_behind_struct_field3.stderr
@@ -1,15 +1,20 @@
-error: item constrains opaque type that is not in its signature
+error[E0308]: mismatched types
   --> $DIR/hidden_behind_struct_field3.rs:19:27
    |
+LL |     type Assoc2 = impl std::fmt::Debug;
+   |                   -------------------- the expected opaque type
+...
 LL |         vec![Foo { field: () }].into_iter()
-   |                           ^^
+   |                           ^^ expected opaque type, found `()`
    |
-   = note: this item must mention the opaque type in its signature in order to be able to register hidden types
-note: this item must mention the opaque type in its signature in order to be able to register hidden types
+   = note: expected opaque type `<Bar as Trait>::Assoc2`
+                found unit type `()`
+note: this item must have the opaque type in its signature in order to be able to register hidden types
   --> $DIR/hidden_behind_struct_field3.rs:18:8
    |
 LL |     fn foo() -> Self::Assoc {
    |        ^^^
 
 error: aborting due to 1 previous error
 
+For more information about this error, try `rustc --explain E0308`.
diff --git a/tests/ui/type-alias-impl-trait/itiat-allow-nested-closures.bad.stderr b/tests/ui/type-alias-impl-trait/itiat-allow-nested-closures.bad.stderr
@@ -8,6 +8,12 @@ LL |         let _: i32 = closure();
    |                ---   ^^^^^^^^^ expected `i32`, found opaque type
    |                |
    |                expected due to this
+   |
+note: this item must have the opaque type in its signature in order to be able to register hidden types
+  --> $DIR/itiat-allow-nested-closures.rs:13:8
+   |
+LL |     fn bar() -> Self::Assoc {
+   |        ^^^
 
 error[E0308]: mismatched types
   --> $DIR/itiat-allow-nested-closures.rs:22:9

diff --git a/tests/ui/type-alias-impl-trait/multi-error.rs b/tests/ui/type-alias-impl-trait/multi-error.rs
@@ -16,7 +16,6 @@ impl Foo for () {
     type Baz = impl Sized;
     fn foo() -> (Self::Bar<u32>, Self::Baz) {
         //~^ ERROR non-defining opaque type use
-        //~| ERROR non-defining opaque type use
         ((), ())
         //~^ ERROR expected generic type parameter
     }

diff --git a/tests/ui/type-alias-impl-trait/multi-error.stderr b/tests/ui/type-alias-impl-trait/multi-error.stderr
@@ -10,28 +10,15 @@ note: for this opaque type
 LL |     type Bar<T> = impl Sized;
    |                   ^^^^^^^^^^
 
-error[E0792]: non-defining opaque type use in defining scope
-  --> $DIR/multi-error.rs:17:17
-   |
-LL |     fn foo() -> (Self::Bar<u32>, Self::Baz) {
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ argument `u32` is not a generic parameter
-   |
-note: for this opaque type
-  --> $DIR/multi-error.rs:15:19
-   |
-LL |     type Bar<T> = impl Sized;
-   |                   ^^^^^^^^^^
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
 error[E0792]: expected generic type parameter, found `u32`
-  --> $DIR/multi-error.rs:20:9
+  --> $DIR/multi-error.rs:19:9
    |
 LL |     type Bar<T> = impl Sized;
    |              - this generic parameter must be used with a generic type parameter
 ...
 LL |         ((), ())
    |         ^^^^^^^^
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0792`.
diff --git a/tests/ui/type-alias-impl-trait/non-defining-method.rs b/tests/ui/type-alias-impl-trait/non-defining-method.rs
@@ -15,7 +15,6 @@ impl Foo for () {
     type Bar<T> = impl Sized;
     fn foo() -> Self::Bar<u32> {}
     //~^ ERROR non-defining opaque type use
-    //~| ERROR non-defining opaque type use
     //~| ERROR expected generic type parameter, found `u32`
     fn bar<T>() -> Self::Bar<T> {}
 }

diff --git a/tests/ui/type-alias-impl-trait/non-defining-method.stderr b/tests/ui/type-alias-impl-trait/non-defining-method.stderr
@@ -10,19 +10,6 @@ note: for this opaque type
 LL |     type Bar<T> = impl Sized;
    |                   ^^^^^^^^^^
 
-error[E0792]: non-defining opaque type use in defining scope
-  --> $DIR/non-defining-method.rs:16:17
-   |
-LL |     fn foo() -> Self::Bar<u32> {}
-   |                 ^^^^^^^^^^^^^^ argument `u32` is not a generic parameter
-   |
-note: for this opaque type
-  --> $DIR/non-defining-method.rs:15:19
-   |
-LL |     type Bar<T> = impl Sized;
-   |                   ^^^^^^^^^^
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
 error[E0792]: expected generic type parameter, found `u32`
   --> $DIR/non-defining-method.rs:16:32
    |
@@ -31,6 +18,6 @@ LL |     type Bar<T> = impl Sized;
 LL |     fn foo() -> Self::Bar<u32> {}
    |                                ^^
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0792`.