diff options
Diffstat (limited to 'compiler/rustc_resolve/src')
| -rw-r--r-- | compiler/rustc_resolve/src/diagnostics.rs | 76 | ||||
| -rw-r--r-- | compiler/rustc_resolve/src/late.rs | 133 | ||||
| -rw-r--r-- | compiler/rustc_resolve/src/late/diagnostics.rs | 1 | ||||
| -rw-r--r-- | compiler/rustc_resolve/src/lib.rs | 1 |
4 files changed, 169 insertions, 42 deletions
diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs index 74daad08394..d09750fa281 100644 --- a/compiler/rustc_resolve/src/diagnostics.rs +++ b/compiler/rustc_resolve/src/diagnostics.rs @@ -5,6 +5,7 @@ use rustc_ast::{ self as ast, CRATE_NODE_ID, Crate, ItemKind, MetaItemInner, MetaItemKind, ModKind, NodeId, Path, }; use rustc_ast_pretty::pprust; +use rustc_attr_data_structures::{self as attr, Stability}; use rustc_data_structures::fx::FxHashSet; use rustc_data_structures::unord::UnordSet; use rustc_errors::codes::*; @@ -110,6 +111,7 @@ pub(crate) struct ImportSuggestion { pub via_import: bool, /// An extra note that should be issued if this item is suggested pub note: Option<String>, + pub is_stable: bool, } /// Adjust the impl span so that just the `impl` keyword is taken by removing @@ -1172,13 +1174,16 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> { ThinVec::<ast::PathSegment>::new(), true, start_did.is_local() || !self.tcx.is_doc_hidden(start_did), + true, )]; let mut worklist_via_import = vec![]; - while let Some((in_module, path_segments, accessible, doc_visible)) = match worklist.pop() { - None => worklist_via_import.pop(), - Some(x) => Some(x), - } { + while let Some((in_module, path_segments, accessible, doc_visible, is_stable)) = + match worklist.pop() { + None => worklist_via_import.pop(), + Some(x) => Some(x), + } + { let in_module_is_extern = !in_module.def_id().is_local(); in_module.for_each_child(self, |this, ident, ns, name_binding| { // Avoid non-importable candidates. @@ -1258,6 +1263,27 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> { candidates.remove(idx); } + let is_stable = if is_stable + && let Some(did) = did + && this.is_stable(did, path.span) + { + true + } else { + false + }; + + // Rreplace unstable suggestions if we meet a new stable one, + // and do nothing if any other situation. For example, if we + // meet `std::ops::Range` after `std::range::legacy::Range`, + // we will remove the latter and then insert the former. + if is_stable + && let Some(idx) = candidates + .iter() + .position(|v: &ImportSuggestion| v.did == did && !v.is_stable) + { + candidates.remove(idx); + } + if candidates.iter().all(|v: &ImportSuggestion| v.did != did) { // See if we're recommending TryFrom, TryInto, or FromIterator and add // a note about editions @@ -1289,6 +1315,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> { doc_visible: child_doc_visible, note, via_import, + is_stable, }); } } @@ -1315,8 +1342,15 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> { if !is_extern_crate_that_also_appears_in_prelude || alias_import { // add the module to the lookup if seen_modules.insert(module.def_id()) { - if via_import { &mut worklist_via_import } else { &mut worklist } - .push((module, path_segments, child_accessible, child_doc_visible)); + if via_import { &mut worklist_via_import } else { &mut worklist }.push( + ( + module, + path_segments, + child_accessible, + child_doc_visible, + is_stable && this.is_stable(module.def_id(), name_binding.span), + ), + ); } } } @@ -1326,6 +1360,34 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> { candidates } + fn is_stable(&self, did: DefId, span: Span) -> bool { + if did.is_local() { + return true; + } + + match self.tcx.lookup_stability(did) { + Some(Stability { + level: attr::StabilityLevel::Unstable { implied_by, .. }, + feature, + .. + }) => { + if span.allows_unstable(feature) { + true + } else if self.tcx.features().enabled(feature) { + true + } else if let Some(implied_by) = implied_by + && self.tcx.features().enabled(implied_by) + { + true + } else { + false + } + } + Some(_) => true, + None => false, + } + } + /// When name resolution fails, this method can be used to look up candidate /// entities with the expected name. It allows filtering them using the /// supplied predicate (which should be used to only accept the types of @@ -2431,7 +2493,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> { let Res::Def(DefKind::Macro(MacroKind::Bang), _) = binding.res() else { return None; }; - let module_name = crate_module.kind.name().unwrap_or(kw::Empty); + let module_name = crate_module.kind.name().unwrap_or(kw::Crate); let import_snippet = match import.kind { ImportKind::Single { source, target, .. } if source != target => { format!("{source} as {target}") diff --git a/compiler/rustc_resolve/src/late.rs b/compiler/rustc_resolve/src/late.rs index faee0e7dd5f..1b682d0cf8a 100644 --- a/compiler/rustc_resolve/src/late.rs +++ b/compiler/rustc_resolve/src/late.rs @@ -111,6 +111,19 @@ enum PatBoundCtx { Or, } +/// Tracks bindings resolved within a pattern. This serves two purposes: +/// +/// - This tracks when identifiers are bound multiple times within a pattern. In a product context, +/// this is an error. In an or-pattern, this lets us reuse the same resolution for each instance. +/// See `fresh_binding` and `resolve_pattern_inner` for more information. +/// +/// - The guard expression of a guard pattern may use bindings from within the guard pattern, but +/// not from elsewhere in the pattern containing it. This allows us to isolate the bindings in the +/// subpattern to construct the scope for the guard. +/// +/// Each identifier must map to at most one distinct [`Res`]. +type PatternBindings = SmallVec<[(PatBoundCtx, FxIndexMap<Ident, Res>); 1]>; + /// Does this the item (from the item rib scope) allow generic parameters? #[derive(Copy, Clone, Debug)] pub(crate) enum HasGenericParams { @@ -786,7 +799,14 @@ impl<'ra: 'ast, 'ast, 'tcx> Visitor<'ast> for LateResolutionVisitor<'_, 'ast, 'r fn visit_pat(&mut self, p: &'ast Pat) { let prev = self.diag_metadata.current_pat; self.diag_metadata.current_pat = Some(p); - visit::walk_pat(self, p); + + if let PatKind::Guard(subpat, _) = &p.kind { + // We walk the guard expression in `resolve_pattern_inner`. Don't resolve it twice. + self.visit_pat(subpat); + } else { + visit::walk_pat(self, p); + } + self.diag_metadata.current_pat = prev; } fn visit_local(&mut self, local: &'ast Local) { @@ -2297,7 +2317,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { fn resolve_fn_params( &mut self, has_self: bool, - inputs: impl Iterator<Item = (Option<&'ast Pat>, &'ast Ty)>, + inputs: impl Iterator<Item = (Option<&'ast Pat>, &'ast Ty)> + Clone, ) -> Result<LifetimeRes, (Vec<MissingLifetime>, Vec<ElisionFnParameter>)> { enum Elision { /// We have not found any candidate. @@ -2319,15 +2339,20 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { let mut parameter_info = Vec::new(); let mut all_candidates = Vec::new(); + // Resolve and apply bindings first so diagnostics can see if they're used in types. let mut bindings = smallvec![(PatBoundCtx::Product, Default::default())]; - for (index, (pat, ty)) in inputs.enumerate() { - debug!(?pat, ?ty); + for (pat, _) in inputs.clone() { + debug!("resolving bindings in pat = {pat:?}"); self.with_lifetime_rib(LifetimeRibKind::Elided(LifetimeRes::Infer), |this| { if let Some(pat) = pat { this.resolve_pattern(pat, PatternSource::FnParam, &mut bindings); } }); + } + self.apply_pattern_bindings(bindings); + for (index, (pat, ty)) in inputs.enumerate() { + debug!("resolving type for pat = {pat:?}, ty = {ty:?}"); // Record elision candidates only for this parameter. debug_assert_matches!(self.lifetime_elision_candidates, None); self.lifetime_elision_candidates = Some(Default::default()); @@ -3615,16 +3640,10 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { self.visit_path(&delegation.path, delegation.id); let Some(body) = &delegation.body else { return }; self.with_rib(ValueNS, RibKind::FnOrCoroutine, |this| { - // `PatBoundCtx` is not necessary in this context - let mut bindings = smallvec![(PatBoundCtx::Product, Default::default())]; - let span = delegation.path.segments.last().unwrap().ident.span; - this.fresh_binding( - Ident::new(kw::SelfLower, span), - delegation.id, - PatternSource::FnParam, - &mut bindings, - ); + let ident = Ident::new(kw::SelfLower, span.normalize_to_macro_rules()); + let res = Res::Local(delegation.id); + this.innermost_rib_bindings(ValueNS).insert(ident, res); this.visit_block(body); }); } @@ -3635,6 +3654,7 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { for Param { pat, .. } in params { this.resolve_pattern(pat, PatternSource::FnParam, &mut bindings); } + this.apply_pattern_bindings(bindings); }); for Param { ty, .. } in params { self.visit_ty(ty); @@ -3851,13 +3871,32 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { fn resolve_pattern_top(&mut self, pat: &'ast Pat, pat_src: PatternSource) { let mut bindings = smallvec![(PatBoundCtx::Product, Default::default())]; self.resolve_pattern(pat, pat_src, &mut bindings); + self.apply_pattern_bindings(bindings); + } + + /// Apply the bindings from a pattern to the innermost rib of the current scope. + fn apply_pattern_bindings(&mut self, mut pat_bindings: PatternBindings) { + let rib_bindings = self.innermost_rib_bindings(ValueNS); + let Some((_, pat_bindings)) = pat_bindings.pop() else { + bug!("tried applying nonexistent bindings from pattern"); + }; + + if rib_bindings.is_empty() { + // Often, such as for match arms, the bindings are introduced into a new rib. + // In this case, we can move the bindings over directly. + *rib_bindings = pat_bindings; + } else { + rib_bindings.extend(pat_bindings); + } } + /// Resolve bindings in a pattern. `apply_pattern_bindings` must be called after to introduce + /// the bindings into scope. fn resolve_pattern( &mut self, pat: &'ast Pat, pat_src: PatternSource, - bindings: &mut SmallVec<[(PatBoundCtx, FxHashSet<Ident>); 1]>, + bindings: &mut PatternBindings, ) { // We walk the pattern before declaring the pattern's inner bindings, // so that we avoid resolving a literal expression to a binding defined @@ -3890,9 +3929,9 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { #[tracing::instrument(skip(self, bindings), level = "debug")] fn resolve_pattern_inner( &mut self, - pat: &Pat, + pat: &'ast Pat, pat_src: PatternSource, - bindings: &mut SmallVec<[(PatBoundCtx, FxHashSet<Ident>); 1]>, + bindings: &mut PatternBindings, ) { // Visit all direct subpatterns of this pattern. pat.walk(&mut |pat| { @@ -3950,6 +3989,31 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { // Prevent visiting `ps` as we've already done so above. return false; } + PatKind::Guard(ref subpat, ref guard) => { + // Add a new set of bindings to the stack to collect bindings in `subpat`. + bindings.push((PatBoundCtx::Product, Default::default())); + // Resolving `subpat` adds bindings onto the newly-pushed context. After, the + // total number of contexts on the stack should be the same as before. + let binding_ctx_stack_len = bindings.len(); + self.resolve_pattern_inner(subpat, pat_src, bindings); + assert_eq!(bindings.len(), binding_ctx_stack_len); + // These bindings, but none from the surrounding pattern, are visible in the + // guard; put them in scope and resolve `guard`. + let subpat_bindings = bindings.pop().unwrap().1; + self.with_rib(ValueNS, RibKind::Normal, |this| { + *this.innermost_rib_bindings(ValueNS) = subpat_bindings.clone(); + this.resolve_expr(guard, None); + }); + // Propagate the subpattern's bindings upwards. + // FIXME(guard_patterns): For `if let` guards, we'll also need to get the + // bindings introduced by the guard from its rib and propagate them upwards. + // This will require checking the identifiers for overlaps with `bindings`, like + // what `fresh_binding` does (ideally sharing its logic). To keep them separate + // from `subpat_bindings`, we can introduce a fresh rib for the guard. + bindings.last_mut().unwrap().1.extend(subpat_bindings); + // Prevent visiting `subpat` as we've already done so above. + return false; + } _ => {} } true @@ -3988,20 +4052,17 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { ident: Ident, pat_id: NodeId, pat_src: PatternSource, - bindings: &mut SmallVec<[(PatBoundCtx, FxHashSet<Ident>); 1]>, + bindings: &mut PatternBindings, ) -> Res { - // Add the binding to the local ribs, if it doesn't already exist in the bindings map. + // Add the binding to the bindings map, if it doesn't already exist. // (We must not add it if it's in the bindings map because that breaks the assumptions // later passes make about or-patterns.) let ident = ident.normalize_to_macro_rules(); - let mut bound_iter = bindings.iter().filter(|(_, set)| set.contains(&ident)); // Already bound in a product pattern? e.g. `(a, a)` which is not allowed. - let already_bound_and = bound_iter.clone().any(|(ctx, _)| *ctx == PatBoundCtx::Product); - // Already bound in an or-pattern? e.g. `V1(a) | V2(a)`. - // This is *required* for consistency which is checked later. - let already_bound_or = bound_iter.any(|(ctx, _)| *ctx == PatBoundCtx::Or); - + let already_bound_and = bindings + .iter() + .any(|(ctx, map)| *ctx == PatBoundCtx::Product && map.contains_key(&ident)); if already_bound_and { // Overlap in a product pattern somewhere; report an error. use ResolutionError::*; @@ -4014,19 +4075,23 @@ impl<'a, 'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> { self.report_error(ident.span, error(ident)); } - // Record as bound. - bindings.last_mut().unwrap().1.insert(ident); - - if already_bound_or { + // Already bound in an or-pattern? e.g. `V1(a) | V2(a)`. + // This is *required* for consistency which is checked later. + let already_bound_or = bindings + .iter() + .find_map(|(ctx, map)| if *ctx == PatBoundCtx::Or { map.get(&ident) } else { None }); + let res = if let Some(&res) = already_bound_or { // `Variant1(a) | Variant2(a)`, ok // Reuse definition from the first `a`. - self.innermost_rib_bindings(ValueNS)[&ident] - } else { - // A completely fresh binding is added to the set. - let res = Res::Local(pat_id); - self.innermost_rib_bindings(ValueNS).insert(ident, res); res - } + } else { + // A completely fresh binding is added to the map. + Res::Local(pat_id) + }; + + // Record as bound. + bindings.last_mut().unwrap().1.insert(ident, res); + res } fn innermost_rib_bindings(&mut self, ns: Namespace) -> &mut FxIndexMap<Ident, Res> { diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs index d4fe446cc9f..b538be34f31 100644 --- a/compiler/rustc_resolve/src/late/diagnostics.rs +++ b/compiler/rustc_resolve/src/late/diagnostics.rs @@ -2501,6 +2501,7 @@ impl<'ast, 'ra: 'ast, 'tcx> LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> { doc_visible, note: None, via_import: false, + is_stable: true, }, )); } else { diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs index 4c47e9ed699..9ba70abd4d9 100644 --- a/compiler/rustc_resolve/src/lib.rs +++ b/compiler/rustc_resolve/src/lib.rs @@ -10,7 +10,6 @@ #![allow(internal_features)] #![allow(rustc::diagnostic_outside_of_impl)] #![allow(rustc::untranslatable_diagnostic)] -#![cfg_attr(bootstrap, feature(let_chains))] #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")] #![doc(rust_logo)] #![feature(assert_matches)] |