Fix scope test bug

This involved fixing how the ScopeResolver handles local bindings. I
probably want to rewrite much of that code.

schala-lang/language/src/ast/visitor.rs

@@ -8,7 +8,7 @@ pub enum Recursion {
 
 pub trait ASTVisitor: Sized {
     fn expression(&mut self, _expression: &Expression) -> Recursion { Recursion::Continue }
-    fn declaration(&mut self, _declaration: &Declaration) -> Recursion { Recursion::Continue }
+    fn declaration(&mut self, _declaration: &Declaration, _id: &ItemId) -> Recursion { Recursion::Continue }
 
     fn import(&mut self, _import: &ImportSpecifier) -> Recursion { Recursion::Continue }
     fn module(&mut self, _module: &ModuleSpecifier) -> Recursion { Recursion::Continue }
@@ -28,7 +28,7 @@ pub fn walk_block<V: ASTVisitor>(v: &mut V, block: &Block) {
                 walk_expression(v, expr);
             }
             Declaration(ref decl) => {
-                walk_declaration(v, decl);
+                walk_declaration(v, decl, &statement.id);
             }
             Import(ref import_spec) => {
                 v.import(import_spec);
@@ -42,10 +42,10 @@ pub fn walk_block<V: ASTVisitor>(v: &mut V, block: &Block) {
     }
 }
 
-fn walk_declaration<V: ASTVisitor>(v: &mut V, decl: &Declaration) {
+fn walk_declaration<V: ASTVisitor>(v: &mut V, decl: &Declaration, id: &ItemId) {
     use Declaration::*;
 
-    if let Recursion::Continue = v.declaration(decl) {
+    if let Recursion::Continue = v.declaration(decl, id) {
         match decl {
             FuncDecl(_sig, block) => {
                 walk_block(v, block);

schala-lang/language/src/reduced_ir/mod.rs

@@ -91,6 +91,11 @@ impl<'a> Reducer<'a> {
                     self.insert_function_definition(item_id, statements);
                     None
                 },
+                ast::Declaration::Binding { constant, expr, ..} => {
+                    let symbol = self.symbol_table.lookup_symbol(item_id).unwrap();
+                    Some(Statement::Binding { id: symbol.def_id.clone(), constant: *constant, expr: self.expression(&expr) })
+                },
+
                 _ => None
             },
             _ => None

schala-lang/language/src/symbol_table/mod.rs

@@ -283,11 +283,12 @@ impl SymbolTable {
     /// Register a new mapping of a fully-qualified symbol name (e.g. `Option::Some`)
     /// to a Symbol, a descriptor of what that name refers to.
     fn add_symbol(&mut self, id: &ItemId, fqsn: Fqsn, spec: SymbolSpec) {
+        let def_id = self.def_id_store.fresh();
         let symbol = Rc::new(Symbol {
             local_name: fqsn.local_name(),
             fully_qualified_name: fqsn.clone(),
             spec,
-            def_id: self.def_id_store.fresh(),
+            def_id,
         });
         self.symbol_trie.insert(&fqsn);
         self.fqsn_to_symbol.insert(fqsn, symbol.clone());

schala-lang/language/src/symbol_table/resolver.rs

@@ -8,14 +8,13 @@ use crate::util::ScopeStack;
 enum NameType {
     //TODO eventually this needs to support closures
     Param(u8), //TODO handle implications of functions being limited to 255 params
-    LocalVariable,
+    LocalVariable(ItemId),
     Import(Fqsn),
 }
 
 #[derive(Debug)]
 enum ScopeType {
     Function {
-        #[allow(dead_code)]
         name: Rc<String>
     },
     Lambda,
@@ -71,6 +70,8 @@ impl<'a> ScopeResolver<'a> {
     fn lookup_name_in_scope(&mut self, name: &QualifiedName) {
         let QualifiedName { id, components } = name;
         //TODO handle a "partial" qualified name
+        //TODO some of these if lets that look into the fqsn_to_symbol table should probaby fail
+        //with an error
         if components.len() == 1 {
             let local_name: Rc<String> = components[0].clone();
             let name_type = self.lexical_scopes.lookup(&local_name);
@@ -86,10 +87,11 @@ impl<'a> ScopeResolver<'a> {
                     let fqsn = Fqsn { scopes: vec![Scope::Name(local_name.clone())] };
                     self.symbol_table.add_symbol(id, fqsn, spec);
                 }
-                Some(NameType::LocalVariable) => {
-                    let spec = SymbolSpec::LocalVariable;
-                    let fqsn = Fqsn { scopes: vec![Scope::Name(local_name.clone())] };
-                    self.symbol_table.add_symbol(id, fqsn, spec);
+                Some(NameType::LocalVariable(item_id)) => {
+                    let symbol = self.symbol_table.id_to_symbol.get(&item_id).cloned();
+                    if let Some(symbol) = symbol {
+                        self.symbol_table.id_to_symbol.insert(id.clone(), symbol);
+                    }
                 },
                 None => {
                     //TODO see if I can reduce this duplicate code
@@ -158,8 +160,12 @@ impl<'a> ASTVisitor for ScopeResolver<'a> {
         Recursion::Continue
     }
 
-    fn declaration(&mut self, declaration: &Declaration) -> Recursion {
-        let is_function_scope = matches!(self.lexical_scopes.get_name(), Some(ScopeType::Function { .. }));
+    fn declaration(&mut self, declaration: &Declaration, id: &ItemId) -> Recursion {
+        let cur_function_name = match self.lexical_scopes.get_name() {
+            //TODO this needs to be a fqsn
+            Some(ScopeType::Function { name }) => Some(name.clone()),
+            _ => None
+        };
         match declaration {
             Declaration::FuncDecl(signature, block) => {
                 let param_names = signature.params.iter().map(|param| param.name.clone());
@@ -178,8 +184,13 @@ impl<'a> ASTVisitor for ScopeResolver<'a> {
                 walk_block(&mut new_resolver, block);
                 Recursion::Stop
             }
-            Declaration::Binding { name, .. } if is_function_scope => {
-                self.lexical_scopes.insert(name.clone(), NameType::LocalVariable);
+            Declaration::Binding { name, .. } => {
+                if let Some(fn_name) = cur_function_name {
+                    // We are within a function scope
+                    let fqsn = Fqsn { scopes: vec![Scope::Name(fn_name.clone()), Scope::Name(name.clone())] };
+                    self.symbol_table.add_symbol(id, fqsn, SymbolSpec::LocalVariable);
+                    self.lexical_scopes.insert(name.clone(), NameType::LocalVariable(id.clone()));
+                }
                 Recursion::Continue
             }
             _ => Recursion::Continue

schala-lang/language/src/tree_walk_eval/test.rs

@@ -39,10 +39,10 @@ fn function_eval() {
 
 #[test]
 fn scopes() {
-    /*
   let scope_ok = r#"
     let a = 20
     fn haha() {
+      let something = 38
       let a = 10
       a
     }
@@ -60,6 +60,5 @@ fn scopes() {
     a
     "#;
     eval_assert(scope_ok, "20");
-    */
 }