Fix duplicate method definition bugs

compiler/erg_common/dict.rs

@@ -153,6 +153,14 @@ impl<K: Hash + Eq, V> Dict<K, V> {
         self.dict.get_mut(k)
     }
 
+    pub fn get_key_value<Q: ?Sized>(&self, k: &Q) -> Option<(&K, &V)>
+    where
+        K: Borrow<Q>,
+        Q: Hash + Eq,
+    {
+        self.dict.get_key_value(k)
+    }
+
     #[inline]
     pub fn contains_key<Q: ?Sized>(&self, k: &Q) -> bool
     where

compiler/erg_compiler/codegen.rs

@@ -202,7 +202,7 @@ fn convert_to_python_attr(class: &str, uniq_obj_name: Option<&str>, name: Str) -
         ("Array!", _, "push!") => Str::ever("append"),
         ("Complex" | "Real" | "Int" | "Nat" | "Float", _, "Real") => Str::ever("real"),
         ("Complex" | "Real" | "Int" | "Nat" | "Float", _, "Imag") => Str::ever("imag"),
-        (_, _, "new" | "__new__") => Str::ever("__call__"),
+        (_, _, "__new__") => Str::ever("__call__"),
         ("StringIO!", _, "getvalue!") => Str::ever("getvalue"),
         ("Module", Some("importlib"), "reload!") => Str::ever("reload"),
         ("Module", Some("random"), "randint!") => Str::ever("randint"),

compiler/erg_compiler/context/inquire.rs

@@ -80,6 +80,10 @@ impl Context {
             })
     }
 
+    pub(crate) fn get_local_kv(&self, name: &str) -> Option<(&VarName, &VarInfo)> {
+        self.locals.get_key_value(name)
+    }
+
     fn get_context(
         &self,
         obj: &hir::Expr,

compiler/erg_compiler/context/mod.rs

@@ -490,6 +490,20 @@ impl Context {
         Self::poly_class(name, vec![], super_classes, super_traits, level)
     }
 
+    #[inline]
+    pub fn methods<S: Into<Str>>(name: S, level: usize) -> Self {
+        Self::with_capacity(
+            name.into(),
+            ContextKind::MethodDefs,
+            vec![],
+            None,
+            vec![],
+            vec![],
+            2,
+            level,
+        )
+    }
+
     #[inline]
     pub fn poly_patch<S: Into<Str>>(
         name: S,

compiler/erg_compiler/context/register.rs

@@ -508,6 +508,7 @@ impl Context {
         Ok(())
     }
 
+    /// e.g. .new
     fn register_auto_impl(
         &mut self,
         name: &'static str,
@@ -524,6 +525,23 @@ impl Context {
         }
     }
 
+    /// e.g. ::__new__
+    fn register_fixed_auto_impl(
+        &mut self,
+        name: &'static str,
+        t: Type,
+        muty: Mutability,
+        vis: Visibility,
+    ) {
+        let name = VarName::from_static(name);
+        if self.locals.get(&name).is_some() {
+            panic!("already registered: {name}");
+        } else {
+            self.locals
+                .insert(name, VarInfo::new(t, muty, vis, VarKind::FixedAuto, None));
+        }
+    }
+
     fn _register_gen_decl(&mut self, name: VarName, t: Type, vis: Visibility) {
         if self.decls.get(&name).is_some() {
             panic!("already registered: {name}");
@@ -577,11 +595,13 @@ impl Context {
                 if gen.t.is_monomorphic() {
                     let super_traits = gen.impls.iter().map(|to| to.typ().clone()).collect();
                     let mut ctx = Self::mono_class(gen.t.name(), vec![], super_traits, self.level);
+                    let mut methods = Self::methods(gen.t.name(), self.level);
                     let require = gen.require_or_sup.typ().clone();
                     let new_t = func1(require, gen.t.clone());
-                    ctx.register_auto_impl("__new__", new_t.clone(), Immutable, Private);
+                    methods.register_fixed_auto_impl("__new__", new_t.clone(), Immutable, Private);
                     // 必要なら、ユーザーが独自に上書きする
-                    ctx.register_auto_impl("new", new_t, Immutable, Public);
+                    methods.register_auto_impl("new", new_t, Immutable, Public);
+                    ctx.method_defs.push((gen.t.clone(), methods));
                     self.register_gen_mono_type(gen, ctx, Const);
                 } else {
                     todo!()
@@ -593,6 +613,7 @@ impl Context {
                     let super_traits = gen.impls.iter().map(|to| to.typ().clone()).collect();
                     let mut ctx =
                         Self::mono_class(gen.t.name(), super_classes, super_traits, self.level);
+                    let mut methods = Self::methods(gen.t.name(), self.level);
                     if let Some(sup) = self.rec_get_const_obj(&gen.require_or_sup.typ().name()) {
                         let sup = enum_unwrap!(sup, ValueObj::Type);
                         let param_t = match sup {
@@ -607,9 +628,15 @@ impl Context {
                             param_t.clone()
                         };
                         let new_t = func1(param_t, gen.t.clone());
-                        ctx.register_auto_impl("__new__", new_t.clone(), Immutable, Private);
+                        methods.register_fixed_auto_impl(
+                            "__new__",
+                            new_t.clone(),
+                            Immutable,
+                            Private,
+                        );
                         // 必要なら、ユーザーが独自に上書きする
-                        ctx.register_auto_impl("new", new_t, Immutable, Public);
+                        methods.register_auto_impl("new", new_t, Immutable, Public);
+                        ctx.method_defs.push((gen.t.clone(), methods));
                         self.register_gen_mono_type(gen, ctx, Const);
                     } else {
                         todo!("super class not found")

compiler/erg_compiler/error.rs

@@ -331,6 +331,30 @@ impl TyCheckError {
         )
     }
 
+    pub fn duplicate_definition_error(
+        errno: usize,
+        loc: Location,
+        caused_by: Str,
+        name: &str,
+    ) -> Self {
+        let name = readable_name(name);
+        Self::new(
+            ErrorCore::new(
+                errno,
+                NameError,
+                loc,
+                switch_lang!(
+                    "japanese" => format!("{name}は既に定義されています"),
+                    "simplified_chinese" => format!("{name}已定义"),
+                    "traditional_chinese" => format!("{name}已定義"),
+                    "english" => format!("{name} is already defined"),
+                ),
+                Option::<Str>::None,
+            ),
+            caused_by,
+        )
+    }
+
     pub fn violate_decl_error(
         errno: usize,
         loc: Location,

compiler/erg_compiler/link.rs

@@ -50,12 +50,12 @@ impl Linker {
                 Expr::Methods(methods) => match &methods.class {
                     TypeSpec::PreDeclTy(PreDeclTypeSpec::Simple(simple)) => {
                         if let Some(pos) = self.def_root_pos_map.get(simple.name.inspect()) {
-                            let mut type_def = match new.remove(*pos) {
-                                Expr::ClassDef(type_def) => type_def,
+                            let mut class_def = match new.remove(*pos) {
+                                Expr::ClassDef(class_def) => class_def,
                                 _ => unreachable!(),
                             };
-                            type_def.methods_list.push(methods);
-                            new.insert(*pos, Expr::ClassDef(type_def));
+                            class_def.methods_list.push(methods);
+                            new.insert(*pos, Expr::ClassDef(class_def));
                         } else {
                             log!("{}", simple.name.inspect());
                             log!("{}", self.def_root_pos_map);

compiler/erg_compiler/lower.rs

@@ -570,10 +570,33 @@ impl ASTLowerer {
                 }
             }
             match self.ctx.pop() {
-                Ok(ctx) => {
-                    self.check_override(&class, &ctx);
+                Ok(methods) => {
+                    self.check_override(&class, &methods);
                     if let Some((_, class_root)) = self.ctx.rec_get_mut_nominal_type_ctx(&class) {
-                        class_root.method_defs.push((class, ctx));
+                        for (newly_defined_name, _vi) in methods.locals.iter() {
+                            for (_, already_defined_methods) in class_root.method_defs.iter_mut() {
+                                // TODO: 特殊化なら同じ名前でもOK
+                                // TODO: 定義のメソッドもエラー表示
+                                if let Some((_already_defined_name, already_defined_vi)) =
+                                    already_defined_methods
+                                        .get_local_kv(&newly_defined_name.inspect())
+                                {
+                                    if already_defined_vi.kind != VarKind::Auto {
+                                        self.errs.push(LowerError::duplicate_definition_error(
+                                            line!() as usize,
+                                            newly_defined_name.loc(),
+                                            methods.name.clone(),
+                                            newly_defined_name.inspect(),
+                                        ));
+                                    } else {
+                                        already_defined_methods
+                                            .locals
+                                            .remove(&newly_defined_name.inspect()[..]);
+                                    }
+                                }
+                            }
+                        }
+                        class_root.method_defs.push((class, methods));
                     } else {
                         todo!()
                     }

compiler/erg_compiler/varinfo.rs

@@ -68,6 +68,7 @@ pub enum VarKind {
         default: DefaultInfo,
     },
     Auto,
+    FixedAuto,
     DoesNotExist,
     Builtin,
 }