First bits of traits and generic function params

Author: cburgdorf

crates/analyzer/src/context.rs

@@ -508,7 +508,7 @@ impl CallType {
             // check that this is the `Context` struct defined in `std`
             // this should be deleted once associated functions are supported and we can
             // define unsafe constructors in Fe
-            struct_.name == "Context" && struct_.id.module(db).ingot(db).name(db) == "std"
+            struct_.name == "Context" && struct_.id.module(db).is_in_std(db)
         } else {
             self.function().map(|id| id.is_unsafe(db)).unwrap_or(false)
         }

crates/analyzer/src/db.rs

@@ -1,8 +1,8 @@
 use crate::context::{Analysis, Constant, FunctionBody};
 use crate::errors::{ConstEvalError, TypeError};
 use crate::namespace::items::{
-    self, ContractFieldId, ContractId, DepGraphWrapper, EventId, FunctionId, IngotId, Item,
-    ModuleConstantId, ModuleId, StructFieldId, StructId, TypeAliasId,
+    self, ContractFieldId, ContractId, DepGraphWrapper, EventId, FunctionId, Impl, IngotId, Item,
+    ModuleConstantId, ModuleId, StructFieldId, StructId, TraitId, TypeAliasId,
 };
 use crate::namespace::types;
 use fe_common::db::{SourceDb, SourceDbStorage, Upcast, UpcastMut};
@@ -24,6 +24,8 @@ pub trait AnalyzerDb: SourceDb + Upcast<dyn SourceDb> + UpcastMut<dyn SourceDb>
     #[salsa::interned]
     fn intern_struct(&self, data: Rc<items::Struct>) -> StructId;
     #[salsa::interned]
+    fn intern_trait(&self, data: Rc<items::Trait>) -> TraitId;
+    #[salsa::interned]
     fn intern_struct_field(&self, data: Rc<items::StructField>) -> StructFieldId;
     #[salsa::interned]
     fn intern_type_alias(&self, data: Rc<items::TypeAlias>) -> TypeAliasId;
@@ -60,6 +62,8 @@ pub trait AnalyzerDb: SourceDb + Upcast<dyn SourceDb> + UpcastMut<dyn SourceDb>
     fn module_is_incomplete(&self, module: ModuleId) -> bool;
     #[salsa::invoke(queries::module::module_all_items)]
     fn module_all_items(&self, module: ModuleId) -> Rc<[Item]>;
+    #[salsa::invoke(queries::module::module_all_impls)]
+    fn module_all_impls(&self, module: ModuleId) -> Rc<[Impl]>;
     #[salsa::invoke(queries::module::module_item_map)]
     fn module_item_map(&self, module: ModuleId) -> Analysis<Rc<IndexMap<SmolStr, Item>>>;
     #[salsa::invoke(queries::module::module_contracts)]
@@ -154,6 +158,10 @@ pub trait AnalyzerDb: SourceDb + Upcast<dyn SourceDb> + UpcastMut<dyn SourceDb>
     #[salsa::invoke(queries::structs::struct_dependency_graph)]
     fn struct_dependency_graph(&self, id: StructId) -> Analysis<DepGraphWrapper>;
 
+    // Trait
+    #[salsa::invoke(queries::traits::trait_type)]
+    fn trait_type(&self, id: TraitId) -> Rc<types::Trait>;
+
     // Event
     #[salsa::invoke(queries::events::event_type)]
     fn event_type(&self, event: EventId) -> Analysis<Rc<types::Event>>;

crates/analyzer/src/db/queries.rs

@@ -4,4 +4,5 @@ pub mod functions;
 pub mod ingots;
 pub mod module;
 pub mod structs;
+pub mod traits;
 pub mod types;

crates/analyzer/src/db/queries/functions.rs

@@ -1,9 +1,11 @@
 use crate::context::{AnalyzerContext, CallType, FunctionBody};
 use crate::db::{Analysis, AnalyzerDb};
 use crate::errors::TypeError;
-use crate::namespace::items::{DepGraph, DepGraphWrapper, DepLocality, FunctionId, Item, TypeDef};
+use crate::namespace::items::{
+    Class, DepGraph, DepGraphWrapper, DepLocality, FunctionId, Item, TypeDef,
+};
 use crate::namespace::scopes::{BlockScope, BlockScopeType, FunctionScope, ItemScope};
-use crate::namespace::types::{self, Contract, CtxDecl, SelfDecl, Struct, Type};
+use crate::namespace::types::{self, Contract, CtxDecl, Generic, SelfDecl, Struct, Type};
 use crate::traversal::functions::traverse_statements;
 use crate::traversal::types::type_desc;
 use fe_common::diagnostics::Label;
@@ -30,6 +32,17 @@ pub fn function_signature(
     let mut names = HashMap::new();
     let mut labels = HashMap::new();
 
+    if let (Some(Class::Contract(_)), true) = (fn_parent, function.is_generic(db)) {
+        scope.fancy_error(
+            "generic function parameters aren't yet supported in contract functions",
+            vec![Label::primary(
+                function.data(db).ast.kind.generic_params.span,
+                "This can not appear here",
+            )],
+            vec!["Hint: Struct functions can have generic parameters".into()],
+        );
+    }
+
     let params = def
         .args
         .iter()
@@ -55,7 +68,7 @@ pub fn function_signature(
                 None
             }
             ast::FunctionArg::Regular(reg) => {
-                let typ = type_desc(&mut scope, &reg.typ).and_then(|typ| match typ {
+                let typ = resolve_function_param_type(db, function, &mut scope, &reg.typ).and_then(|typ| match typ {
                     typ if typ.has_fixed_size() => Ok(typ),
                     _ => Err(TypeError::new(scope.error(
                         "function parameter types must have fixed size",
@@ -192,6 +205,40 @@ pub fn function_signature(
     }
 }
 
+pub fn resolve_function_param_type(
+    db: &dyn AnalyzerDb,
+    function: FunctionId,
+    context: &mut dyn AnalyzerContext,
+    desc: &Node<ast::TypeDesc>,
+) -> Result<Type, TypeError> {
+    // First check if the param type is a local generic of the function. This won't hold when in the future
+    // generics can appear on the contract, struct or module level but it could be good enough for now.
+    if let ast::TypeDesc::Base { base } = &desc.kind {
+        if let Some(val) = function.generic_param(db, base) {
+            let bounds = match val {
+                ast::GenericParameter::Unbounded(_) => vec![],
+                ast::GenericParameter::Bounded { bound, .. } => match type_desc(context, &bound)? {
+                    Type::Trait(trait_ty) => vec![trait_ty.id],
+                    other => {
+                        context.error(
+                            &format!("expected trait, found type `{}`", other),
+                            bound.span,
+                            "not a trait",
+                        );
+                        vec![]
+                    }
+                },
+            };
+
+            return Ok(Type::Generic(Generic {
+                name: base.clone(),
+                bounds,
+            }));
+        }
+    }
+    type_desc(context, desc)
+}
+
 /// Gather context information for a function body and check for type errors.
 pub fn function_body(db: &dyn AnalyzerDb, function: FunctionId) -> Analysis<Rc<FunctionBody>> {
     let def = &function.data(db).ast.kind;

crates/analyzer/src/db/queries/module.rs

@@ -2,8 +2,8 @@ use crate::context::{Analysis, AnalyzerContext, Constant};
 use crate::db::AnalyzerDb;
 use crate::errors::{self, ConstEvalError, TypeError};
 use crate::namespace::items::{
-    Contract, ContractId, Event, Function, Item, ModuleConstant, ModuleConstantId, ModuleId,
-    ModuleSource, Struct, StructId, TypeAlias, TypeDef,
+    Contract, ContractId, Event, Function, Impl, Item, ModuleConstant, ModuleConstantId, ModuleId,
+    ModuleSource, Struct, StructId, Trait, TypeAlias, TypeDef,
 };
 use crate::namespace::scopes::ItemScope;
 use crate::namespace::types::{self, Type};
@@ -59,7 +59,6 @@ pub fn module_is_incomplete(db: &dyn AnalyzerDb, module: ModuleId) -> bool {
 
 pub fn module_all_items(db: &dyn AnalyzerDb, module: ModuleId) -> Rc<[Item]> {
     let body = &module.ast(db).body;
-
     body.iter()
         .filter_map(|stmt| match stmt {
             ast::ModuleStmt::TypeAlias(node) => Some(Item::Type(TypeDef::Alias(
@@ -94,8 +93,13 @@ pub fn module_all_items(db: &dyn AnalyzerDb, module: ModuleId) -> Rc<[Item]> {
                     parent: None,
                 }))))
             }
-            ast::ModuleStmt::Pragma(_) => None,
-            ast::ModuleStmt::Use(_) => None,
+            ast::ModuleStmt::Trait(node) => Some(Item::Type(TypeDef::Trait(db.intern_trait(
+                Rc::new(Trait {
+                    ast: node.clone(),
+                    module,
+                }),
+            )))),
+            ast::ModuleStmt::Pragma(_) | ast::ModuleStmt::Use(_) | ast::ModuleStmt::Impl(_) => None,
             ast::ModuleStmt::Event(node) => Some(Item::Event(db.intern_event(Rc::new(Event {
                 ast: node.clone(),
                 module,
@@ -106,6 +110,35 @@ pub fn module_all_items(db: &dyn AnalyzerDb, module: ModuleId) -> Rc<[Item]> {
         .collect()
 }
 
+pub fn module_all_impls(db: &dyn AnalyzerDb, module: ModuleId) -> Rc<[Impl]> {
+    let body = &module.ast(db).body;
+    body.iter()
+        .filter_map(|stmt| match stmt {
+            ast::ModuleStmt::Impl(impl_node) => {
+                let treit = module
+                    .items(db)
+                    .get(&impl_node.kind.impl_trait.kind)
+                    .cloned();
+
+                let mut scope = ItemScope::new(db, module);
+                let receiver_type = type_desc(&mut scope, &impl_node.kind.receiver).unwrap();
+
+                if let Some(Item::Type(TypeDef::Trait(val))) = treit {
+                    Some(Impl {
+                        trait_id: val,
+                        receiver: receiver_type,
+                        ast: impl_node.clone(),
+                        module,
+                    })
+                } else {
+                    None
+                }
+            }
+            _ => None,
+        })
+        .collect()
+}
+
 pub fn module_item_map(
     db: &dyn AnalyzerDb,
     module: ModuleId,

crates/analyzer/src/db/queries/traits.rs

@@ -0,0 +1,11 @@
+use crate::namespace::items::TraitId;
+use crate::namespace::types;
+use crate::AnalyzerDb;
+use std::rc::Rc;
+
+pub fn trait_type(db: &dyn AnalyzerDb, trait_: TraitId) -> Rc<types::Trait> {
+    Rc::new(types::Trait {
+        name: trait_.name(db),
+        id: trait_,
+    })
+}