fix: aliases in path (#6399)

compiler/noirc_frontend/src/elaborator/comptime.rs

@@ -91,6 +91,7 @@ impl<'context> Elaborator<'context> {
         let mut elaborator = Elaborator::new(
             self.interner,
             self.def_maps,
+            self.usage_tracker,
             self.crate_id,
             self.debug_comptime_in_file,
             self.interpreter_call_stack.clone(),
@@ -412,6 +413,7 @@ impl<'context> Elaborator<'context> {
                 if let Some(id) = dc_mod::collect_function(
                     self.interner,
                     self.def_maps.get_mut(&self.crate_id).unwrap(),
+                    self.usage_tracker,
                     &function,
                     module_id,
                     self.file,
@@ -461,6 +463,7 @@ impl<'context> Elaborator<'context> {
                 let (global, error) = dc_mod::collect_global(
                     self.interner,
                     self.def_maps.get_mut(&self.crate_id).unwrap(),
+                    self.usage_tracker,
                     Documented::new(global, item.doc_comments),
                     visibility,
                     self.file,
@@ -477,6 +480,7 @@ impl<'context> Elaborator<'context> {
                 if let Some((type_id, the_struct)) = dc_mod::collect_struct(
                     self.interner,
                     self.def_maps.get_mut(&self.crate_id).unwrap(),
+                    self.usage_tracker,
                     Documented::new(struct_def, item.doc_comments),
                     self.file,
                     self.local_module,

compiler/noirc_frontend/src/elaborator/expressions.rs

@@ -591,7 +591,7 @@ impl<'context> Elaborator<'context> {
     pub(super) fn mark_struct_as_constructed(&mut self, struct_type: Shared<StructType>) {
         let struct_type = struct_type.borrow();
         let parent_module_id = struct_type.id.parent_module_id(self.def_maps);
-        self.interner.usage_tracker.mark_as_used(parent_module_id, &struct_type.name);
+        self.usage_tracker.mark_as_used(parent_module_id, &struct_type.name);
     }
 
     /// Resolve all the fields of a struct constructor expression.

compiler/noirc_frontend/src/elaborator/mod.rs

@@ -5,7 +5,8 @@ use std::{
 
 use crate::{
     ast::ItemVisibility, hir::resolution::import::PathResolutionItem,
-    hir_def::traits::ResolvedTraitBound, StructField, StructType, TypeBindings,
+    hir_def::traits::ResolvedTraitBound, usage_tracker::UsageTracker, StructField, StructType,
+    TypeBindings,
 };
 use crate::{
     ast::{
@@ -84,8 +85,8 @@ pub struct Elaborator<'context> {
     pub(crate) errors: Vec<(CompilationError, FileId)>,
 
     pub(crate) interner: &'context mut NodeInterner,
-
     pub(crate) def_maps: &'context mut DefMaps,
+    pub(crate) usage_tracker: &'context mut UsageTracker,
 
     pub(crate) file: FileId,
 
@@ -183,6 +184,7 @@ impl<'context> Elaborator<'context> {
     pub fn new(
         interner: &'context mut NodeInterner,
         def_maps: &'context mut DefMaps,
+        usage_tracker: &'context mut UsageTracker,
         crate_id: CrateId,
         debug_comptime_in_file: Option<FileId>,
         interpreter_call_stack: im::Vector<Location>,
@@ -192,6 +194,7 @@ impl<'context> Elaborator<'context> {
             errors: Vec::new(),
             interner,
             def_maps,
+            usage_tracker,
             file: FileId::dummy(),
             in_unsafe_block: false,
             nested_loops: 0,
@@ -221,6 +224,7 @@ impl<'context> Elaborator<'context> {
         Self::new(
             &mut context.def_interner,
             &mut context.def_maps,
+            &mut context.usage_tracker,
             crate_id,
             debug_comptime_in_file,
             im::Vector::new(),

compiler/noirc_frontend/src/elaborator/patterns.rs

@@ -17,7 +17,7 @@ use crate::{
         stmt::HirPattern,
     },
     node_interner::{DefinitionId, DefinitionKind, ExprId, FuncId, GlobalId, TraitImplKind},
-    Kind, ResolvedGeneric, Shared, StructType, Type, TypeBindings,
+    Kind, ResolvedGeneric, Shared, StructType, Type, TypeAlias, TypeBindings,
 };
 
 use super::{Elaborator, ResolverMeta};
@@ -453,6 +453,30 @@ impl<'context> Elaborator<'context> {
         self.resolve_turbofish_generics(&struct_type.generics, turbofish_generics)
     }
 
+    pub(super) fn resolve_alias_turbofish_generics(
+        &mut self,
+        type_alias: &TypeAlias,
+        generics: Vec<Type>,
+        unresolved_turbofish: Option<Vec<UnresolvedType>>,
+        span: Span,
+    ) -> Vec<Type> {
+        let Some(turbofish_generics) = unresolved_turbofish else {
+            return generics;
+        };
+
+        if turbofish_generics.len() != generics.len() {
+            self.push_err(TypeCheckError::GenericCountMismatch {
+                item: format!("alias {}", type_alias.name),
+                expected: generics.len(),
+                found: turbofish_generics.len(),
+                span,
+            });
+            return generics;
+        }
+
+        self.resolve_turbofish_generics(&type_alias.generics, turbofish_generics)
+    }
+
     pub(super) fn resolve_turbofish_generics(
         &mut self,
         generics: &[ResolvedGeneric],
@@ -526,10 +550,36 @@ impl<'context> Elaborator<'context> {
                     generics.span,
                 )
             }
-            PathResolutionItem::TypeAliasFunction(_type_alias_id, Some(generics), _func_id) => {
-                // TODO: https://github.com/noir-lang/noir/issues/6311
-                self.push_err(TypeCheckError::UnsupportedTurbofishUsage { span: generics.span });
-                Vec::new()
+            PathResolutionItem::TypeAliasFunction(type_alias_id, generics, _func_id) => {
+                let type_alias = self.interner.get_type_alias(type_alias_id);
+                let type_alias = type_alias.borrow();
+                let alias_generics = vecmap(&type_alias.generics, |generic| {
+                    self.interner.next_type_variable_with_kind(generic.kind())
+                });
+
+                // First solve the generics on the alias, if any
+                let generics = if let Some(generics) = generics {
+                    self.resolve_alias_turbofish_generics(
+                        &type_alias,
+                        alias_generics,
+                        Some(generics.generics),
+                        generics.span,
+                    )
+                } else {
+                    alias_generics
+                };
+
+                // Now instantiate the underlying struct with those generics, the struct might
+                // have more generics than those in the alias, like in this example:
+                //
+                // type Alias<T> = Struct<T, i32>;
+                let typ = type_alias.get_type(&generics);
+                let Type::Struct(_, generics) = typ else {
+                    // See https://github.com/noir-lang/noir/issues/6398
+                    panic!("Expected type alias to point to struct")
+                };
+
+                generics
             }
             PathResolutionItem::TraitFunction(_trait_id, Some(generics), _func_id) => {
                 // TODO: https://github.com/noir-lang/noir/issues/6310

compiler/noirc_frontend/src/elaborator/scope.rs

@@ -87,9 +87,10 @@ impl<'context> Elaborator<'context> {
 
         if !self.interner.lsp_mode {
             return resolver.resolve(
+                self.interner,
                 self.def_maps,
                 path,
-                &mut self.interner.usage_tracker,
+                self.usage_tracker,
                 &mut None,
             );
         }
@@ -100,9 +101,10 @@ impl<'context> Elaborator<'context> {
 
         let mut references: Vec<_> = Vec::new();
         let path_resolution = resolver.resolve(
+            self.interner,
             self.def_maps,
             path.clone(),
-            &mut self.interner.usage_tracker,
+            self.usage_tracker,
             &mut Some(&mut references),
         );
 

compiler/noirc_frontend/src/hir/def_collector/dc_crate.rs

@@ -353,8 +353,9 @@ impl DefCollector {
                 let resolved_import = resolve_import(
                     crate_id,
                     &collected_import,
+                    &context.def_interner,
                     &context.def_maps,
-                    &mut context.def_interner.usage_tracker,
+                    &mut context.usage_tracker,
                     &mut Some(&mut references),
                 );
 
@@ -375,8 +376,9 @@ impl DefCollector {
                 resolve_import(
                     crate_id,
                     &collected_import,
+                    &context.def_interner,
                     &context.def_maps,
-                    &mut context.def_interner.usage_tracker,
+                    &mut context.usage_tracker,
                     &mut None,
                 )
             };
@@ -421,7 +423,7 @@ impl DefCollector {
                                 krate: crate_id,
                                 local_id: resolved_import.module_scope,
                             };
-                            context.def_interner.usage_tracker.add_unused_item(
+                            context.usage_tracker.add_unused_item(
                                 module_id,
                                 name.clone(),
                                 UnusedItem::Import,
@@ -501,7 +503,7 @@ impl DefCollector {
         crate_id: CrateId,
         errors: &mut Vec<(CompilationError, FileId)>,
     ) {
-        let unused_imports = context.def_interner.unused_items().iter();
+        let unused_imports = context.usage_tracker.unused_items().iter();
         let unused_imports = unused_imports.filter(|(module_id, _)| module_id.krate == crate_id);
 
         errors.extend(unused_imports.flat_map(|(module_id, usage_tracker)| {
@@ -557,11 +559,12 @@ fn inject_prelude(
         };
 
         if let Ok(PathResolution { item, errors }) = path_resolver::resolve_path(
+            &context.def_interner,
             &context.def_maps,
             ModuleId { krate: crate_id, local_id: crate_root },
             None,
             path,
-            &mut context.def_interner.usage_tracker,
+            &mut context.usage_tracker,
             &mut None,
         ) {
             assert!(errors.is_empty(), "Tried to add private item to prelude");

compiler/noirc_frontend/src/hir/def_collector/dc_mod.rs

@@ -18,7 +18,7 @@ use crate::ast::{
 use crate::hir::resolution::errors::ResolverError;
 use crate::node_interner::{ModuleAttributes, NodeInterner, ReferenceId, StructId};
 use crate::token::SecondaryAttribute;
-use crate::usage_tracker::UnusedItem;
+use crate::usage_tracker::{UnusedItem, UsageTracker};
 use crate::{
     graph::CrateId,
     hir::def_collector::dc_crate::{UnresolvedStruct, UnresolvedTrait},
@@ -147,6 +147,7 @@ impl<'a> ModCollector<'a> {
             let (global, error) = collect_global(
                 &mut context.def_interner,
                 &mut self.def_collector.def_map,
+                &mut context.usage_tracker,
                 global,
                 visibility,
                 self.file_id,
@@ -246,6 +247,7 @@ impl<'a> ModCollector<'a> {
             let Some(func_id) = collect_function(
                 &mut context.def_interner,
                 &mut self.def_collector.def_map,
+                &mut context.usage_tracker,
                 &function.item,
                 module,
                 self.file_id,
@@ -282,6 +284,7 @@ impl<'a> ModCollector<'a> {
             if let Some((id, the_struct)) = collect_struct(
                 &mut context.def_interner,
                 &mut self.def_collector.def_map,
+                &mut context.usage_tracker,
                 struct_definition,
                 self.file_id,
                 self.module_id,
@@ -336,7 +339,7 @@ impl<'a> ModCollector<'a> {
             );
 
             let parent_module_id = ModuleId { krate, local_id: self.module_id };
-            context.def_interner.usage_tracker.add_unused_item(
+            context.usage_tracker.add_unused_item(
                 parent_module_id,
                 name.clone(),
                 UnusedItem::TypeAlias(type_alias_id),
@@ -412,7 +415,7 @@ impl<'a> ModCollector<'a> {
             );
 
             let parent_module_id = ModuleId { krate, local_id: self.module_id };
-            context.def_interner.usage_tracker.add_unused_item(
+            context.usage_tracker.add_unused_item(
                 parent_module_id,
                 name.clone(),
                 UnusedItem::Trait(trait_id),
@@ -897,9 +900,11 @@ fn push_child_module(
     Ok(mod_id)
 }
 
+#[allow(clippy::too_many_arguments)]
 pub fn collect_function(
     interner: &mut NodeInterner,
     def_map: &mut CrateDefMap,
+    usage_tracker: &mut UsageTracker,
     function: &NoirFunction,
     module: ModuleId,
     file: FileId,
@@ -932,7 +937,7 @@ pub fn collect_function(
 
     if !is_test && !is_entry_point_function {
         let item = UnusedItem::Function(func_id);
-        interner.usage_tracker.add_unused_item(module, name.clone(), item, visibility);
+        usage_tracker.add_unused_item(module, name.clone(), item, visibility);
     }
 
     interner.set_doc_comments(ReferenceId::Function(func_id), doc_comments);
@@ -950,9 +955,11 @@ pub fn collect_function(
     Some(func_id)
 }
 
+#[allow(clippy::too_many_arguments)]
 pub fn collect_struct(
     interner: &mut NodeInterner,
     def_map: &mut CrateDefMap,
+    usage_tracker: &mut UsageTracker,
     struct_definition: Documented<NoirStruct>,
     file_id: FileId,
     module_id: LocalModuleId,
@@ -1015,7 +1022,7 @@ pub fn collect_struct(
     let parent_module_id = ModuleId { krate, local_id: module_id };
 
     if !unresolved.struct_def.is_abi() {
-        interner.usage_tracker.add_unused_item(
+        usage_tracker.add_unused_item(
             parent_module_id,
             name.clone(),
             UnusedItem::Struct(id),
@@ -1191,9 +1198,11 @@ pub(crate) fn collect_trait_impl_items(
     (unresolved_functions, associated_types, associated_constants)
 }
 
+#[allow(clippy::too_many_arguments)]
 pub(crate) fn collect_global(
     interner: &mut NodeInterner,
     def_map: &mut CrateDefMap,
+    usage_tracker: &mut UsageTracker,
     global: Documented<LetStatement>,
     visibility: ItemVisibility,
     file_id: FileId,
@@ -1221,7 +1230,7 @@ pub(crate) fn collect_global(
 
     if !is_abi {
         let parent_module_id = ModuleId { krate: crate_id, local_id: module_id };
-        interner.usage_tracker.add_unused_item(
+        usage_tracker.add_unused_item(
             parent_module_id,
             name,
             UnusedItem::Global(global_id),

compiler/noirc_frontend/src/hir/mod.rs

@@ -11,6 +11,7 @@ use crate::graph::{CrateGraph, CrateId};
 use crate::hir_def::function::FuncMeta;
 use crate::node_interner::{FuncId, NodeInterner, StructId};
 use crate::parser::ParserError;
+use crate::usage_tracker::UsageTracker;
 use crate::{Generics, Kind, ParsedModule, ResolvedGeneric, TypeVariable};
 use def_collector::dc_crate::CompilationError;
 use def_map::{Contract, CrateDefMap};
@@ -33,6 +34,7 @@ pub struct Context<'file_manager, 'parsed_files> {
     pub def_interner: NodeInterner,
     pub crate_graph: CrateGraph,
     pub def_maps: BTreeMap<CrateId, CrateDefMap>,
+    pub usage_tracker: UsageTracker,
     // In the WASM context, we take ownership of the file manager,
     // which is why this needs to be a Cow. In all use-cases, the file manager
     // is read-only however, once it has been passed to the Context.
@@ -64,6 +66,7 @@ impl Context<'_, '_> {
         Context {
             def_interner: NodeInterner::default(),
             def_maps: BTreeMap::new(),
+            usage_tracker: UsageTracker::default(),
             visited_files: BTreeMap::new(),
             crate_graph: CrateGraph::default(),
             file_manager: Cow::Owned(file_manager),
@@ -80,6 +83,7 @@ impl Context<'_, '_> {
         Context {
             def_interner: NodeInterner::default(),
             def_maps: BTreeMap::new(),
+            usage_tracker: UsageTracker::default(),
             visited_files: BTreeMap::new(),
             crate_graph: CrateGraph::default(),
             file_manager: Cow::Borrowed(file_manager),