From 6ddccc9a6e81ebd3350568575051ac795184fa81 Mon Sep 17 00:00:00 2001 From: Lukas Wirth Date: Tue, 14 Nov 2023 18:09:28 +0100 Subject: [PATCH] Diagnose some orphan trait impl cases --- crates/hir-ty/src/diagnostics.rs | 6 - crates/hir-ty/src/lib.rs | 1 + crates/hir-ty/src/method_resolution.rs | 56 +++++++++ crates/hir/src/diagnostics.rs | 15 ++- crates/hir/src/lib.rs | 13 ++- .../src/handlers/trait_impl_orphan.rs | 106 ++++++++++++++++++ crates/ide-diagnostics/src/lib.rs | 8 +- crates/ide-diagnostics/src/tests.rs | 15 ++- 8 files changed, 205 insertions(+), 15 deletions(-) create mode 100644 crates/ide-diagnostics/src/handlers/trait_impl_orphan.rs diff --git a/crates/hir-ty/src/diagnostics.rs b/crates/hir-ty/src/diagnostics.rs index ef43ed5c46..c1b3619009 100644 --- a/crates/hir-ty/src/diagnostics.rs +++ b/crates/hir-ty/src/diagnostics.rs @@ -11,9 +11,3 @@ pub use crate::diagnostics::{ }, unsafe_check::{missing_unsafe, unsafe_expressions, UnsafeExpr}, }; - -#[derive(Debug, PartialEq, Eq)] -pub struct IncoherentImpl { - pub file_id: hir_expand::HirFileId, - pub impl_: syntax::AstPtr, -} diff --git a/crates/hir-ty/src/lib.rs b/crates/hir-ty/src/lib.rs index 405bb001b5..35a3a1ad8d 100644 --- a/crates/hir-ty/src/lib.rs +++ b/crates/hir-ty/src/lib.rs @@ -80,6 +80,7 @@ pub use mapping::{ lt_from_placeholder_idx, to_assoc_type_id, to_chalk_trait_id, to_foreign_def_id, to_placeholder_idx, }; +pub use method_resolution::check_orphan_rules; pub use traits::TraitEnvironment; pub use utils::{all_super_traits, is_fn_unsafe_to_call}; diff --git a/crates/hir-ty/src/method_resolution.rs b/crates/hir-ty/src/method_resolution.rs index f3a5f69b2a..87c9328336 100644 --- a/crates/hir-ty/src/method_resolution.rs +++ b/crates/hir-ty/src/method_resolution.rs @@ -862,6 +862,62 @@ fn is_inherent_impl_coherent( } } +/// Checks whether the impl satisfies the orphan rules. +/// +/// Given `impl Trait for T0`, an `impl`` is valid only if at least one of the following is true: +/// - Trait is a local trait +/// - All of +/// - At least one of the types `T0..=Tn`` must be a local type. Let `Ti`` be the first such type. +/// - No uncovered type parameters `P1..=Pn` may appear in `T0..Ti`` (excluding `Ti`) +pub fn check_orphan_rules(db: &dyn HirDatabase, impl_: ImplId) -> bool { + let substs = TyBuilder::placeholder_subst(db, impl_); + let Some(impl_trait) = db.impl_trait(impl_) else { + // not a trait impl + return true; + }; + + let local_crate = impl_.lookup(db.upcast()).container.krate(); + let is_local = |tgt_crate| tgt_crate == local_crate; + + let trait_ref = impl_trait.substitute(Interner, &substs); + let trait_id = from_chalk_trait_id(trait_ref.trait_id); + if is_local(trait_id.module(db.upcast()).krate()) { + // trait to be implemented is local + return true; + } + + let unwrap_fundamental = |ty: Ty| match ty.kind(Interner) { + TyKind::Ref(_, _, referenced) => referenced.clone(), + &TyKind::Adt(AdtId(hir_def::AdtId::StructId(s)), ref subs) => { + let struct_data = db.struct_data(s); + if struct_data.flags.contains(StructFlags::IS_FUNDAMENTAL) { + let next = subs.type_parameters(Interner).next(); + match next { + Some(ty) => ty, + None => ty, + } + } else { + ty + } + } + _ => ty, + }; + // - At least one of the types `T0..=Tn`` must be a local type. Let `Ti`` be the first such type. + let is_not_orphan = trait_ref.substitution.type_parameters(Interner).any(|ty| { + match unwrap_fundamental(ty).kind(Interner) { + &TyKind::Adt(AdtId(id), _) => is_local(id.module(db.upcast()).krate()), + TyKind::Error => true, + TyKind::Dyn(it) => it.principal().map_or(false, |trait_ref| { + is_local(from_chalk_trait_id(trait_ref.trait_id).module(db.upcast()).krate()) + }), + _ => false, + } + }); + // FIXME: param coverage + // - No uncovered type parameters `P1..=Pn` may appear in `T0..Ti`` (excluding `Ti`) + is_not_orphan +} + pub fn iterate_path_candidates( ty: &Canonical, db: &dyn HirDatabase, diff --git a/crates/hir/src/diagnostics.rs b/crates/hir/src/diagnostics.rs index 67d3169243..3a45622675 100644 --- a/crates/hir/src/diagnostics.rs +++ b/crates/hir/src/diagnostics.rs @@ -3,7 +3,7 @@ //! //! This probably isn't the best way to do this -- ideally, diagnostics should //! be expressed in terms of hir types themselves. -pub use hir_ty::diagnostics::{CaseType, IncoherentImpl, IncorrectCase}; +pub use hir_ty::diagnostics::{CaseType, IncorrectCase}; use base_db::CrateId; use cfg::{CfgExpr, CfgOptions}; @@ -38,6 +38,7 @@ diagnostics![ IncorrectCase, InvalidDeriveTarget, IncoherentImpl, + TraitImplOrphan, MacroDefError, MacroError, MacroExpansionParseError, @@ -280,3 +281,15 @@ pub struct MovedOutOfRef { pub ty: Type, pub span: InFile, } + +#[derive(Debug, PartialEq, Eq)] +pub struct IncoherentImpl { + pub file_id: HirFileId, + pub impl_: AstPtr, +} + +#[derive(Debug, PartialEq, Eq)] +pub struct TraitImplOrphan { + pub file_id: HirFileId, + pub impl_: AstPtr, +} diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs index 6fcc02fb9d..dfb0779f10 100644 --- a/crates/hir/src/lib.rs +++ b/crates/hir/src/lib.rs @@ -60,7 +60,7 @@ use hir_def::{ }; use hir_expand::{name::name, MacroCallKind}; use hir_ty::{ - all_super_traits, autoderef, + all_super_traits, autoderef, check_orphan_rules, consteval::{try_const_usize, unknown_const_as_generic, ConstEvalError, ConstExt}, diagnostics::BodyValidationDiagnostic, known_const_to_ast, @@ -95,7 +95,7 @@ pub use crate::{ MacroExpansionParseError, MalformedDerive, MismatchedArgCount, MismatchedTupleStructPatArgCount, MissingFields, MissingMatchArms, MissingUnsafe, MovedOutOfRef, NeedMut, NoSuchField, PrivateAssocItem, PrivateField, - ReplaceFilterMapNextWithFindMap, TypeMismatch, TypedHole, UndeclaredLabel, + ReplaceFilterMapNextWithFindMap, TraitImplOrphan, TypeMismatch, TypedHole, UndeclaredLabel, UnimplementedBuiltinMacro, UnreachableLabel, UnresolvedExternCrate, UnresolvedField, UnresolvedImport, UnresolvedMacroCall, UnresolvedMethodCall, UnresolvedModule, UnresolvedProcMacro, UnusedMut, UnusedVariable, @@ -624,6 +624,11 @@ impl Module { acc.push(IncoherentImpl { impl_: ast_id_map.get(node.ast_id()), file_id }.into()) } + if !impl_def.check_orphan_rules(db) { + let ast_id_map = db.ast_id_map(file_id); + acc.push(TraitImplOrphan { impl_: ast_id_map.get(node.ast_id()), file_id }.into()) + } + for item in impl_def.items(db) { let def: DefWithBody = match item { AssocItem::Function(it) => it.into(), @@ -3406,6 +3411,10 @@ impl Impl { let src = self.source(db)?; src.file_id.as_builtin_derive_attr_node(db.upcast()) } + + pub fn check_orphan_rules(self, db: &dyn HirDatabase) -> bool { + check_orphan_rules(db, self.id) + } } #[derive(Clone, PartialEq, Eq, Debug, Hash)] diff --git a/crates/ide-diagnostics/src/handlers/trait_impl_orphan.rs b/crates/ide-diagnostics/src/handlers/trait_impl_orphan.rs new file mode 100644 index 0000000000..159d87d269 --- /dev/null +++ b/crates/ide-diagnostics/src/handlers/trait_impl_orphan.rs @@ -0,0 +1,106 @@ +use hir::InFile; + +use crate::{Diagnostic, DiagnosticCode, DiagnosticsContext}; + +// Diagnostic: trait-impl-orphan +// +// Only traits defined in the current crate can be implemented for arbitrary types +pub(crate) fn trait_impl_orphan( + ctx: &DiagnosticsContext<'_>, + d: &hir::TraitImplOrphan, +) -> Diagnostic { + Diagnostic::new_with_syntax_node_ptr( + ctx, + DiagnosticCode::RustcHardError("E0117"), + format!("only traits defined in the current crate can be implemented for arbitrary types"), + InFile::new(d.file_id, d.impl_.clone().into()), + ) + // Not yet checked for false positives + .experimental() +} + +#[cfg(test)] +mod tests { + use crate::tests::check_diagnostics; + + #[test] + fn simple() { + check_diagnostics( + r#" +//- /foo.rs crate:foo +pub trait Foo {} +//- /bar.rs crate:bar +pub struct Bar; +//- /main.rs crate:main deps:foo,bar +struct LocalType; +trait LocalTrait {} + impl foo::Foo for bar::Bar {} +//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: only traits defined in the current crate can be implemented for arbitrary types +impl foo::Foo for LocalType {} +impl LocalTrait for bar::Bar {} +"#, + ); + } + + #[test] + fn generics() { + check_diagnostics( + r#" +//- /foo.rs crate:foo +pub trait Foo {} +//- /bar.rs crate:bar +pub struct Bar(T); +//- /main.rs crate:main deps:foo,bar +struct LocalType; +trait LocalTrait {} + impl foo::Foo for bar::Bar {} +//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: only traits defined in the current crate can be implemented for arbitrary types + + impl foo::Foo for bar::Bar> {} +//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: only traits defined in the current crate can be implemented for arbitrary types + + impl foo::Foo> for bar::Bar {} + + impl foo::Foo>> for bar::Bar> {} +//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: only traits defined in the current crate can be implemented for arbitrary types +"#, + ); + } + + #[test] + fn fundamental() { + check_diagnostics( + r#" +//- /foo.rs crate:foo +pub trait Foo {} +//- /bar.rs crate:bar +pub struct Bar(T); +#[lang = "owned_box"] +#[fundamental] +pub struct Box(T); +//- /main.rs crate:main deps:foo,bar +struct LocalType; + impl foo::Foo for bar::Box {} +//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: only traits defined in the current crate can be implemented for arbitrary types + impl foo::Foo for &LocalType {} + impl foo::Foo for bar::Box {} +"#, + ); + } + + #[test] + fn dyn_object() { + check_diagnostics( + r#" +//- /foo.rs crate:foo +pub trait Foo {} +//- /bar.rs crate:bar +pub struct Bar; +//- /main.rs crate:main deps:foo,bar +trait LocalTrait {} +impl foo::Foo for dyn LocalTrait {} +impl foo::Foo for Bar {} +"#, + ); + } +} diff --git a/crates/ide-diagnostics/src/lib.rs b/crates/ide-diagnostics/src/lib.rs index 68d7e99b7b..3226dd29d2 100644 --- a/crates/ide-diagnostics/src/lib.rs +++ b/crates/ide-diagnostics/src/lib.rs @@ -44,6 +44,7 @@ mod handlers { pub(crate) mod private_assoc_item; pub(crate) mod private_field; pub(crate) mod replace_filter_map_next_with_find_map; + pub(crate) mod trait_impl_orphan; pub(crate) mod typed_hole; pub(crate) mod type_mismatch; pub(crate) mod unimplemented_builtin_macro; @@ -301,9 +302,9 @@ pub fn diagnostics( ) })); - let parse = parse.syntax_node(); + let parse = sema.parse(file_id); - for node in parse.descendants() { + for node in parse.syntax().descendants() { handlers::useless_braces::useless_braces(&mut res, file_id, &node); handlers::field_shorthand::field_shorthand(&mut res, file_id, &node); handlers::json_is_not_rust::json_in_items(&sema, &mut res, file_id, &node, config); @@ -358,6 +359,7 @@ pub fn diagnostics( AnyDiagnostic::PrivateAssocItem(d) => handlers::private_assoc_item::private_assoc_item(&ctx, &d), AnyDiagnostic::PrivateField(d) => handlers::private_field::private_field(&ctx, &d), AnyDiagnostic::ReplaceFilterMapNextWithFindMap(d) => handlers::replace_filter_map_next_with_find_map::replace_filter_map_next_with_find_map(&ctx, &d), + AnyDiagnostic::TraitImplOrphan(d) => handlers::trait_impl_orphan::trait_impl_orphan(&ctx, &d), AnyDiagnostic::TypedHole(d) => handlers::typed_hole::typed_hole(&ctx, &d), AnyDiagnostic::TypeMismatch(d) => handlers::type_mismatch::type_mismatch(&ctx, &d), AnyDiagnostic::UndeclaredLabel(d) => handlers::undeclared_label::undeclared_label(&ctx, &d), @@ -386,7 +388,7 @@ pub fn diagnostics( handle_lint_attributes( &ctx.sema, - &parse, + parse.syntax(), &mut rustc_stack, &mut clippy_stack, &mut diagnostics_of_range, diff --git a/crates/ide-diagnostics/src/tests.rs b/crates/ide-diagnostics/src/tests.rs index ee0e035490..ff8f3b2686 100644 --- a/crates/ide-diagnostics/src/tests.rs +++ b/crates/ide-diagnostics/src/tests.rs @@ -5,7 +5,7 @@ use expect_test::Expect; use ide_db::{ assists::AssistResolveStrategy, base_db::{fixture::WithFixture, SourceDatabaseExt}, - RootDatabase, + LineIndexDatabase, RootDatabase, }; use stdx::trim_indent; use test_utils::{assert_eq_text, extract_annotations, MiniCore}; @@ -103,6 +103,7 @@ pub(crate) fn check_diagnostics(ra_fixture: &str) { pub(crate) fn check_diagnostics_with_config(config: DiagnosticsConfig, ra_fixture: &str) { let (db, files) = RootDatabase::with_many_files(ra_fixture); for file_id in files { + let line_index = db.line_index(file_id); let diagnostics = super::diagnostics(&db, &config, &AssistResolveStrategy::All, file_id); let expected = extract_annotations(&db.file_text(file_id)); @@ -136,8 +137,16 @@ pub(crate) fn check_diagnostics_with_config(config: DiagnosticsConfig, ra_fixtur } } if expected != actual { - let fneg = expected.iter().filter(|x| !actual.contains(x)).collect::>(); - let fpos = actual.iter().filter(|x| !expected.contains(x)).collect::>(); + let fneg = expected + .iter() + .filter(|x| !actual.contains(x)) + .map(|(range, s)| (line_index.line_col(range.start()), range, s)) + .collect::>(); + let fpos = actual + .iter() + .filter(|x| !expected.contains(x)) + .map(|(range, s)| (line_index.line_col(range.start()), range, s)) + .collect::>(); panic!("Diagnostic test failed.\nFalse negatives: {fneg:?}\nFalse positives: {fpos:?}"); }