Prevent methods from using names of properties or fields. #1638

releasenotes.md

@@ -21,6 +21,7 @@
 - Indexing an Optional slice would crash in codegen #1636.
 - SimpleHeapAllocator bug when splitting blocks allowed memory overrun.
 - Not possible to alias or take reference for extension methods on non-user defined types. #1637
+- Prevent methods from using names of properties or fields. #1638
 
 ### Stdlib changes
 - Add `io::MultiReader`, `io::MultiWriter`, and `io::TeeReader` structs.

src/compiler/compiler_internal.h

@@ -2255,9 +2255,15 @@ bool parse_stdin(void);
 Path *path_create_from_string(const char *string, uint32_t len, SourceSpan span);
 
 
+typedef enum FindMember
+{
+	METHODS_AND_FIELDS,
+	FIELDS_ONLY
+} FindMember;
+
 void sema_analysis_run(void);
 Decl **sema_decl_stack_store(void);
-Decl *sema_decl_stack_find_decl_member(SemaContext *context, Decl *decl_owner, const char *symbol);
+Decl *sema_decl_stack_find_decl_member(SemaContext *context, Decl *decl_owner, const char *symbol, FindMember find);
 Decl *sema_decl_stack_resolve_symbol(const char *symbol);
 void sema_decl_stack_restore(Decl **state);
 void sema_decl_stack_push(Decl *decl);

src/compiler/sema_decls.c

@@ -2212,6 +2212,103 @@ static inline bool sema_analyse_method(SemaContext *context, Decl *decl)
 
 	// Resolve declaration of parent as needed.
 	if (!sema_resolve_type_decl(context, par_type)) return false;
+	const char *kw = decl->name;
+	const char *errname = NULL;
+	switch (par_type->canonical->type_kind)
+	{
+		case TYPE_ENUM:
+			if (kw == kw_ordinal || kw == kw_nameof)
+			{
+				errname = "an enum";
+				goto NOT_VALID_NAME;
+			}
+			FALLTHROUGH;
+		case TYPE_STRUCT:
+		case TYPE_UNION:
+		{
+			Decl *d = sema_decl_stack_find_decl_member(context, par_type->canonical->decl, kw, FIELDS_ONLY);
+			if (!decl_ok(d)) return false;
+			if (d) RETURN_SEMA_ERROR(decl, "%s already has a field with the same name.", type_quoted_error_string(par_type));
+			break;
+		}
+		case TYPE_FAULTTYPE:
+			if (kw == kw_ordinal || kw == kw_nameof)
+			{
+				errname = "a fault";
+				goto NOT_VALID_NAME;
+			}
+			break;
+		case TYPE_ANYFAULT:
+			if (kw == kw_type || kw == kw_nameof)
+			{
+				errname = "'anyfault'";
+				goto NOT_VALID_NAME;
+			}
+			break;
+		case TYPE_ANY:
+		case TYPE_INTERFACE:
+			if (kw == kw_ptr || kw == kw_type)
+			{
+				errname = "an interface or 'any'";
+				goto NOT_VALID_NAME;
+			}
+			break;
+		case TYPE_SLICE:
+			if (kw == kw_ptr || kw == kw_len)
+			{
+				errname = "a slice";
+				goto NOT_VALID_NAME;
+			}
+			break;
+		case TYPE_VECTOR:
+		case TYPE_INFERRED_VECTOR:
+		{
+			unsigned len = strlen(decl->name);
+			if (len <= 4)
+			{
+				for (unsigned i = 0; i < len; i++)
+				{
+					if (!swizzle[(int) decl->name[i]]) goto NEXT;
+				}
+				RETURN_SEMA_ERROR(decl, "\"%s\" is not a valid method name for a vector, since it matches a swizzle combination.", kw);
+			}
+		}
+		NEXT:;
+			FALLTHROUGH;
+		case TYPE_ARRAY:
+		case TYPE_INFERRED_ARRAY:
+		case TYPE_FLEXIBLE_ARRAY:
+			if (kw == kw_len)
+			{
+				errname = "a vector or array";
+				goto NOT_VALID_NAME;
+			}
+			break;
+		case TYPE_POISONED:
+		case TYPE_VOID:
+		case ALL_FLOATS:
+		case ALL_INTS:
+		case TYPE_BOOL:
+		case TYPE_FUNC_PTR:
+		case TYPE_POINTER:
+		case TYPE_FUNC_RAW:
+		case TYPE_UNTYPED_LIST:
+		case TYPE_BITSTRUCT:
+		case TYPE_DISTINCT:
+			break;
+		case TYPE_TYPEID:
+			if (type_property_by_name(kw) != TYPE_PROPERTY_NONE)
+			{
+				RETURN_SEMA_ERROR(decl, "\"%s\" is not a valid method name for a typeid as this is the name of a type property.", decl->name);
+			}
+			break;
+		case TYPE_TYPEDEF:
+		case TYPE_OPTIONAL:
+		case TYPE_WILDCARD:
+		case TYPE_TYPEINFO:
+		case TYPE_MEMBER:
+			UNREACHABLE
+	}
 	Decl **params = decl->func_decl.signature.params;
 	bool is_dynamic = decl->func_decl.attr_dynamic;
 
@@ -2257,6 +2354,8 @@ static inline bool sema_analyse_method(SemaContext *context, Decl *decl)
 	}
 
 	return true;
+NOT_VALID_NAME:
+	RETURN_SEMA_ERROR(decl, "\"%s\" is not a valid method name for %s, as this would shadow the built-in property '.%s'.", kw, errname, kw);
 }
 
 static const char *attribute_domain_to_string(AttributeDomain domain)

src/compiler/sema_expr.c

@@ -3739,7 +3739,7 @@ static inline bool sema_expr_analyse_type_access(SemaContext *context, Expr *exp
 			UNREACHABLE
 	}
 
-	Decl *member = sema_decl_stack_find_decl_member(context, decl, name);
+	Decl *member = sema_decl_stack_find_decl_member(context, decl, name, METHODS_AND_FIELDS);
 	if (!decl_ok(member)) return false;
 	if (!member)
 	{
@@ -3859,7 +3859,7 @@ static inline bool sema_expr_analyse_member_access(SemaContext *context, Expr *e
 	}
 
 	Decl *underlying_type_decl = underlying_type->decl;
-	Decl *member = sema_decl_stack_find_decl_member(context, underlying_type_decl, name);
+	Decl *member = sema_decl_stack_find_decl_member(context, underlying_type_decl, name, METHODS_AND_FIELDS);
 	if (!decl_ok(member)) return false;
 	if (!member || !(decl_is_struct_type(member) || member->decl_kind == DECL_VAR || member->decl_kind == DECL_BITSTRUCT))
 	{
@@ -5012,7 +5012,7 @@ static inline bool sema_expr_analyse_access(SemaContext *context, Expr *expr, bo
 	// 10. Dump all members and methods into a decl stack.
 	Decl *decl = type->decl;
 
-	Decl *member = sema_decl_stack_find_decl_member(context, decl, kw);
+	Decl *member = sema_decl_stack_find_decl_member(context, decl, kw, METHODS_AND_FIELDS);
 	if (!decl_ok(member)) return false;
 	if (member && decl_is_enum_kind(decl) && member->decl_kind == DECL_VAR && sema_cast_const(parent))
 	{
@@ -7982,7 +7982,7 @@ static inline bool sema_expr_analyse_decl_element(SemaContext *context, Designat
 		}
 		return false;
 	}
-	Decl *member = sema_decl_stack_find_decl_member(context, actual_type->decl, kw);
+	Decl *member = sema_decl_stack_find_decl_member(context, actual_type->decl, kw, METHODS_AND_FIELDS);
 	if (!decl_ok(member)) return false;
 	if (!member)
 	{
@@ -9134,14 +9134,6 @@ static inline BuiltinFunction builtin_by_name(const char *name)
 	return BUILTIN_NONE;
 }
 
-static inline TypeProperty type_property_by_name(const char *name)
-{
-	for (unsigned i = 0; i < NUMBER_OF_TYPE_PROPERTIES; i++)
-	{
-		if (type_property_list[i] == name) return (TypeProperty)i;
-	}
-	return TYPE_PROPERTY_NONE;
-}
 
 static inline bool sema_expr_analyse_retval(SemaContext *context, Expr *expr)
 {

src/compiler/sema_internal.h

@@ -242,4 +242,13 @@ static inline StorageType sema_resolve_storage_type(SemaContext *context, Type *
 		default:
 			return STORAGE_NORMAL;
 	}
-}
+}
+
+static inline TypeProperty type_property_by_name(const char *name)
+{
+	for (unsigned i = 0; i < NUMBER_OF_TYPE_PROPERTIES; i++)
+	{
+		if (type_property_list[i] == name) return (TypeProperty)i;
+	}
+	return TYPE_PROPERTY_NONE;
+}

src/compiler/sema_name_resolution.c

@@ -80,11 +80,14 @@ static bool add_interface_to_decl_stack(SemaContext *context, Decl *decl)
 	return true;
 }
 
-static bool add_members_to_decl_stack(SemaContext *context, Decl *decl)
+static bool add_members_to_decl_stack(SemaContext *context, Decl *decl, FindMember find)
 {
-	FOREACH(Decl *, func, decl->methods)
+	if (find != FIELDS_ONLY)
 	{
-		sema_decl_stack_push(func);
+		FOREACH(Decl *, func, decl->methods)
+		{
+			sema_decl_stack_push(func);
+		}
 	}
 	while (decl->decl_kind == DECL_DISTINCT)
 	{
@@ -96,7 +99,7 @@ static bool add_members_to_decl_stack(SemaContext *context, Decl *decl)
 	{
 		FOREACH(Decl *, member, decl->enums.parameters) sema_decl_stack_push(member);
 	}
-	if (decl->decl_kind == DECL_INTERFACE)
+	if (decl->decl_kind == DECL_INTERFACE && find != FIELDS_ONLY)
 	{
 		if (!add_interface_to_decl_stack(context, decl)) return false;
 	}
@@ -106,7 +109,7 @@ static bool add_members_to_decl_stack(SemaContext *context, Decl *decl)
 		{
 			if (member->name == NULL)
 			{
-				if (!add_members_to_decl_stack(context, member)) return false;
+				if (!add_members_to_decl_stack(context, member, find)) return false;
 				continue;
 			}
 			sema_decl_stack_push(member);
@@ -115,10 +118,10 @@ static bool add_members_to_decl_stack(SemaContext *context, Decl *decl)
 	return true;
 }
 
-Decl *sema_decl_stack_find_decl_member(SemaContext *context, Decl *decl_owner, const char *symbol)
+Decl *sema_decl_stack_find_decl_member(SemaContext *context, Decl *decl_owner, const char *symbol, FindMember find)
 {
 	Decl **state = sema_decl_stack_store();
-	if (!add_members_to_decl_stack(context, decl_owner)) return poisoned_decl;
+	if (!add_members_to_decl_stack(context, decl_owner, find)) return poisoned_decl;
 	Decl *member = sema_decl_stack_resolve_symbol(symbol);
 	sema_decl_stack_restore(state);
 	return member;

test/test_suite/methods/method_name_collision.c3

@@ -0,0 +1,7 @@
+module testc3;
+
+fn bool any.type(self) { // #error: is not a valid method name
+return true;
+}
+
+fn void main() {}