diff options
Diffstat (limited to 'compiler/rustc_lint/src/internal.rs')
| -rw-r--r-- | compiler/rustc_lint/src/internal.rs | 132 |
1 files changed, 85 insertions, 47 deletions
diff --git a/compiler/rustc_lint/src/internal.rs b/compiler/rustc_lint/src/internal.rs index 016ff17f5d7..e1fbe39222b 100644 --- a/compiler/rustc_lint/src/internal.rs +++ b/compiler/rustc_lint/src/internal.rs @@ -1,10 +1,10 @@ //! Some lints that are only useful in the compiler or crates that use compiler internals, such as //! Clippy. -use rustc_hir::HirId; use rustc_hir::def::Res; use rustc_hir::def_id::DefId; -use rustc_middle::ty::{self, GenericArgsRef, Ty as MiddleTy}; +use rustc_hir::{Expr, ExprKind, HirId}; +use rustc_middle::ty::{self, ClauseKind, GenericArgsRef, PredicatePolarity, TraitPredicate, Ty}; use rustc_session::{declare_lint_pass, declare_tool_lint}; use rustc_span::hygiene::{ExpnKind, MacroKind}; use rustc_span::{Span, sym}; @@ -56,25 +56,6 @@ impl LateLintPass<'_> for DefaultHashTypes { } } -/// Helper function for lints that check for expressions with calls and use typeck results to -/// get the `DefId` and `GenericArgsRef` of the function. -fn typeck_results_of_method_fn<'tcx>( - cx: &LateContext<'tcx>, - expr: &hir::Expr<'_>, -) -> Option<(Span, DefId, ty::GenericArgsRef<'tcx>)> { - match expr.kind { - hir::ExprKind::MethodCall(segment, ..) - if let Some(def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id) => - { - Some((segment.ident.span, def_id, cx.typeck_results().node_args(expr.hir_id))) - } - _ => match cx.typeck_results().node_type(expr.hir_id).kind() { - &ty::FnDef(def_id, args) => Some((expr.span, def_id, args)), - _ => None, - }, - } -} - declare_tool_lint! { /// The `potential_query_instability` lint detects use of methods which can lead to /// potential query instability, such as iterating over a `HashMap`. @@ -101,10 +82,12 @@ declare_tool_lint! { declare_lint_pass!(QueryStability => [POTENTIAL_QUERY_INSTABILITY, UNTRACKED_QUERY_INFORMATION]); -impl LateLintPass<'_> for QueryStability { - fn check_expr(&mut self, cx: &LateContext<'_>, expr: &hir::Expr<'_>) { - let Some((span, def_id, args)) = typeck_results_of_method_fn(cx, expr) else { return }; - if let Ok(Some(instance)) = ty::Instance::try_resolve(cx.tcx, cx.typing_env(), def_id, args) +impl<'tcx> LateLintPass<'tcx> for QueryStability { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) { + if let Some((callee_def_id, span, generic_args, _recv, _args)) = + get_callee_span_generic_args_and_args(cx, expr) + && let Ok(Some(instance)) = + ty::Instance::try_resolve(cx.tcx, cx.typing_env(), callee_def_id, generic_args) { let def_id = instance.def_id(); if cx.tcx.has_attr(def_id, sym::rustc_lint_query_instability) { @@ -113,7 +96,15 @@ impl LateLintPass<'_> for QueryStability { span, QueryInstability { query: cx.tcx.item_name(def_id) }, ); + } else if has_unstable_into_iter_predicate(cx, callee_def_id, generic_args) { + let call_span = span.with_hi(expr.span.hi()); + cx.emit_span_lint( + POTENTIAL_QUERY_INSTABILITY, + call_span, + QueryInstability { query: sym::into_iter }, + ); } + if cx.tcx.has_attr(def_id, sym::rustc_lint_untracked_query_information) { cx.emit_span_lint( UNTRACKED_QUERY_INFORMATION, @@ -125,6 +116,64 @@ impl LateLintPass<'_> for QueryStability { } } +fn has_unstable_into_iter_predicate<'tcx>( + cx: &LateContext<'tcx>, + callee_def_id: DefId, + generic_args: GenericArgsRef<'tcx>, +) -> bool { + let Some(into_iterator_def_id) = cx.tcx.get_diagnostic_item(sym::IntoIterator) else { + return false; + }; + let Some(into_iter_fn_def_id) = cx.tcx.lang_items().into_iter_fn() else { + return false; + }; + let predicates = cx.tcx.predicates_of(callee_def_id).instantiate(cx.tcx, generic_args); + for (predicate, _) in predicates { + let ClauseKind::Trait(TraitPredicate { trait_ref, polarity: PredicatePolarity::Positive }) = + predicate.kind().skip_binder() + else { + continue; + }; + // Does the function or method require any of its arguments to implement `IntoIterator`? + if trait_ref.def_id != into_iterator_def_id { + continue; + } + let Ok(Some(instance)) = + ty::Instance::try_resolve(cx.tcx, cx.typing_env(), into_iter_fn_def_id, trait_ref.args) + else { + continue; + }; + // Does the input type's `IntoIterator` implementation have the + // `rustc_lint_query_instability` attribute on its `into_iter` method? + if cx.tcx.has_attr(instance.def_id(), sym::rustc_lint_query_instability) { + return true; + } + } + false +} + +/// Checks whether an expression is a function or method call and, if so, returns its `DefId`, +/// `Span`, `GenericArgs`, and arguments. This is a slight augmentation of a similarly named Clippy +/// function, `get_callee_generic_args_and_args`. +fn get_callee_span_generic_args_and_args<'tcx>( + cx: &LateContext<'tcx>, + expr: &'tcx Expr<'tcx>, +) -> Option<(DefId, Span, GenericArgsRef<'tcx>, Option<&'tcx Expr<'tcx>>, &'tcx [Expr<'tcx>])> { + if let ExprKind::Call(callee, args) = expr.kind + && let callee_ty = cx.typeck_results().expr_ty(callee) + && let ty::FnDef(callee_def_id, generic_args) = callee_ty.kind() + { + return Some((*callee_def_id, callee.span, generic_args, None, args)); + } + if let ExprKind::MethodCall(segment, recv, args, _) = expr.kind + && let Some(method_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id) + { + let generic_args = cx.typeck_results().node_args(expr.hir_id); + return Some((method_def_id, segment.ident.span, generic_args, Some(recv), args)); + } + None +} + declare_tool_lint! { /// The `usage_of_ty_tykind` lint detects usages of `ty::TyKind::<kind>`, /// where `ty::<kind>` would suffice. @@ -461,33 +510,22 @@ declare_tool_lint! { declare_lint_pass!(Diagnostics => [UNTRANSLATABLE_DIAGNOSTIC, DIAGNOSTIC_OUTSIDE_OF_IMPL]); impl LateLintPass<'_> for Diagnostics { - fn check_expr(&mut self, cx: &LateContext<'_>, expr: &hir::Expr<'_>) { + fn check_expr<'tcx>(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'tcx>) { let collect_args_tys_and_spans = |args: &[hir::Expr<'_>], reserve_one_extra: bool| { let mut result = Vec::with_capacity(args.len() + usize::from(reserve_one_extra)); result.extend(args.iter().map(|arg| (cx.typeck_results().expr_ty(arg), arg.span))); result }; // Only check function calls and method calls. - let (span, def_id, fn_gen_args, arg_tys_and_spans) = match expr.kind { - hir::ExprKind::Call(callee, args) => { - match cx.typeck_results().node_type(callee.hir_id).kind() { - &ty::FnDef(def_id, fn_gen_args) => { - (callee.span, def_id, fn_gen_args, collect_args_tys_and_spans(args, false)) - } - _ => return, // occurs for fns passed as args - } - } - hir::ExprKind::MethodCall(_segment, _recv, args, _span) => { - let Some((span, def_id, fn_gen_args)) = typeck_results_of_method_fn(cx, expr) - else { - return; - }; - let mut args = collect_args_tys_and_spans(args, true); - args.insert(0, (cx.tcx.types.self_param, _recv.span)); // dummy inserted for `self` - (span, def_id, fn_gen_args, args) - } - _ => return, + let Some((def_id, span, fn_gen_args, recv, args)) = + get_callee_span_generic_args_and_args(cx, expr) + else { + return; }; + let mut arg_tys_and_spans = collect_args_tys_and_spans(args, recv.is_some()); + if let Some(recv) = recv { + arg_tys_and_spans.insert(0, (cx.tcx.types.self_param, recv.span)); // dummy inserted for `self` + } Self::diagnostic_outside_of_impl(cx, span, expr.hir_id, def_id, fn_gen_args); Self::untranslatable_diagnostic(cx, def_id, &arg_tys_and_spans); @@ -496,7 +534,7 @@ impl LateLintPass<'_> for Diagnostics { impl Diagnostics { // Is the type `{D,Subd}iagMessage`? - fn is_diag_message<'cx>(cx: &LateContext<'cx>, ty: MiddleTy<'cx>) -> bool { + fn is_diag_message<'cx>(cx: &LateContext<'cx>, ty: Ty<'cx>) -> bool { if let Some(adt_def) = ty.ty_adt_def() && let Some(name) = cx.tcx.get_diagnostic_name(adt_def.did()) && matches!(name, sym::DiagMessage | sym::SubdiagMessage) @@ -510,7 +548,7 @@ impl Diagnostics { fn untranslatable_diagnostic<'cx>( cx: &LateContext<'cx>, def_id: DefId, - arg_tys_and_spans: &[(MiddleTy<'cx>, Span)], + arg_tys_and_spans: &[(Ty<'cx>, Span)], ) { let fn_sig = cx.tcx.fn_sig(def_id).instantiate_identity().skip_binder(); let predicates = cx.tcx.predicates_of(def_id).instantiate_identity(cx.tcx).predicates; |