Implement all checker specification for Objective-C class implementations and `objc_ivar_get` intrinsic

base/intrinsics/intrinsics.odin

@@ -364,7 +364,7 @@ objc_find_selector     :: proc($name: string) -> objc_SEL   ---
 objc_register_selector :: proc($name: string) -> objc_SEL   ---
 objc_find_class        :: proc($name: string) -> objc_Class ---
 objc_register_class    :: proc($name: string) -> objc_Class ---
-objc_ivar_get          :: proc(self: ^$T, $U: typeid) -> ^U ---
+objc_ivar_get          :: proc(self: ^$T) -> ^$U ---
 
 valgrind_client_request :: proc(default: uintptr, request: uintptr, a0, a1, a2, a3, a4: uintptr) -> uintptr ---
 

src/check_builtin.cpp

@@ -391,7 +391,6 @@ gb_internal bool check_builtin_objc_procedure(CheckerContext *c, Operand *operan
 	case BuiltinProc_objc_ivar_get:
 	{
 		Type *self_type = nullptr;
-		Type *ivar_type = nullptr;
 
 		Operand self = {};
 		check_expr_or_type(c, &self, ce->args[0]);
@@ -416,40 +415,21 @@ gb_internal bool check_builtin_objc_procedure(CheckerContext *c, Operand *operan
 
 		if (!(self_type->kind == Type_Named &&
 			self_type->Named.type_name != nullptr &&
-				self_type->Named.type_name->TypeName.objc_class_name != "")) {
+			self_type->Named.type_name->TypeName.objc_class_name != "")) {
 			gbString t = type_to_string(self_type);
 			error(self.expr, "'%.*s' expected a named type with the attribute @(objc_class=<string>) , got type %s", LIT(builtin_name), t);
 			gb_string_free(t);
 			return false;
 		}
 
-		if (self_type->Named.type_name->TypeName.objc_ivar == nullptr) {
+		Type *ivar_type = self_type->Named.type_name->TypeName.objc_ivar;
+		if (ivar_type == nullptr) {
 			gbString t = type_to_string(self_type);
 			error(self.expr, "'%.*s' requires that type %s have the attribute @(objc_ivar=<ivar_type_name>).", LIT(builtin_name), t);
 			gb_string_free(t);
 			return false;
 		}
 
-		Operand ivar = {};
-		check_expr_or_type(c, &ivar, ce->args[1]);
-		if (ivar.mode == Addressing_Type) {
-			ivar_type = ivar.type;
-		} else {
-			return false;
-		}
-
-		if (self_type->Named.type_name->TypeName.objc_ivar != ivar_type) {
-			gbString name_self     = type_to_string(self_type);
-			gbString name_expected = type_to_string(self_type->Named.type_name->TypeName.objc_ivar);
-			gbString name_given    = type_to_string(ivar_type);
-			error(self.expr, "'%.*s' ivar type %s does not match @objc_ivar type %s on Objective-C class %s.",
-				  LIT(builtin_name), name_given, name_expected, name_self);
-			gb_string_free(name_self);
-			gb_string_free(name_expected);
-			gb_string_free(name_given);
-			return false;
-		}
-
 		if (type_hint != nullptr && type_hint->kind == Type_Pointer && type_hint->Pointer.elem == ivar_type) {
 			operand->type = type_hint;
 		} else {
@@ -457,8 +437,8 @@ gb_internal bool check_builtin_objc_procedure(CheckerContext *c, Operand *operan
 		}
 
 		operand->mode = Addressing_Value;
-
 		return true;
+
 	} break;
 	}
 }

src/check_decl.cpp

@@ -565,31 +565,41 @@ gb_internal void check_type_decl(CheckerContext *ctx, Entity *e, Ast *init_expr,
 					check_single_global_entity(ctx->checker, super->Named.type_name, super->Named.type_name->decl_info);
 
 					if (super->kind != Type_Named) {
+						// TODO(harold): Show the current superclass token too
 						error(e->token, "@(objc_superclass) Referenced type must be a named struct");
 						break;
 					}
 
 					Type* named_type = base_type(super->Named.type_name->type);
 					if (!is_type_objc_object(named_type)) {
+						// TODO(harold): Show the current superclass token too
 						error(e->token, "@(objc_superclass) Superclass must be an Objective-C class");
 						break;
 					}
 
+					if (named_type->Named.type_name->TypeName.objc_class_name == "") {
+						// TODO(harold): Show the current superclass token too
+						error(e->token, "@(objc_superclass) Superclass must be have a valid @(objc_class) attribute");
+						break;
+					}
+
 					super = named_type->Named.type_name->TypeName.objc_superclass;
 				}
 			} else {
 				if (ac.objc_superclass != nullptr) {
-					error(e->token, "@(objc_superclass) can only be applied when the @(obj_implement) attribute is also applied");
+					error(e->token, "@(objc_superclass) may only be applied when the @(obj_implement) attribute is also applied");
 				} else if (ac.objc_ivar != nullptr) {
-					error(e->token, "@(objc_ivar) can only be applied when the @(obj_implement) attribute is also applied");
+					error(e->token, "@(objc_ivar) may only be applied when the @(obj_implement) attribute is also applied");
 				} else if (ac.objc_context_provider != nullptr) {
-					error(e->token, "@(objc_context_provider) can only be applied when the @(obj_implement) attribute is also applied");
+					error(e->token, "@(objc_context_provider) may only be applied when the @(obj_implement) attribute is also applied");
 				}
 			}
 
 			if (type_size_of(e->type) > 0) {
 				error(e->token, "@(objc_class) marked type must be of zero size");
 			}
+		} else if (ac.objc_is_implementation) {
+			error(e->token, "@(objc_implement) may only be applied when the @(objc_class) attribute is also applied");
 		}
 	}
 
@@ -994,7 +1004,7 @@ gb_internal void check_objc_methods(CheckerContext *ctx, Entity *e, AttributeCon
 		error(e->token, "@(objc_name) is required with @(objc_type)");
 	} else {
 		Type *t = ac.objc_type;
-		if (t->kind == Type_Named) {
+		if (t->kind == Type_Named) {	// TODO(harold): Shouldn't this be an error otherwise? Or is it checked elsehwere?
 			Entity *tn = t->Named.type_name;
 
 			GB_ASSERT(tn->kind == Entity_TypeName);
@@ -1003,20 +1013,32 @@ gb_internal void check_objc_methods(CheckerContext *ctx, Entity *e, AttributeCon
 				error(e->token, "@(objc_name) attribute may only be applied to procedures and types within the same scope");
 			} else {
 
-				if (ac.objc_is_implementation) {
+				// Enable implementation by default if the class is an implementer too and
+				// @objc_implement was not set to false explicitly in this proc.
+				bool implement = tn->TypeName.objc_is_implementation;
+				if (ac.objc_is_disabled_implement) {
+					implement = false;
+				}
+
+				if (implement) {
 					GB_ASSERT(e->kind == Entity_Procedure);
 
-					Type *proc_type = e->type;
+					auto &proc = e->type->Proc;
+					Type &first_param = proc.param_count > 0 ? proc.params[0] : *t_untyped_nil;
 
 					if (!tn->TypeName.objc_is_implementation) {
 						error(e->token, "@(objc_is_implement) attribute may only be applied to procedures whose class also have @(objc_is_implement) applied");
-					} else if (proc_type->Proc.calling_convention == ProcCC_Odin && !tn->TypeName.objc_context_provider) {
+					} else if (!ac.objc_is_class_method && !(first_param.kind == Type_Pointer && first_param.Pointer.elem == t)) {
+						error(e->token, "Objective-C instance methods implementations require the first parameter to be a pointer to the class type set by @(objc_type)");
+					} else if (proc.calling_convention == ProcCC_Odin && !tn->TypeName.objc_context_provider) {
 						error(e->token, "Objective-C methods with Odin calling convention can only be used with classes that have @(objc_context_provider) set");
-					} else if (ac.objc_is_class_method && proc_type->Proc.calling_convention != ProcCC_CDecl) {
+					} else if (ac.objc_is_class_method && proc.calling_convention != ProcCC_CDecl) {
 						error(e->token, "Objective-C class methods (objc_is_class_method=true) that have @objc_is_implementation can only use \"c\" calling convention");
+					} else if (proc.result_count > 1) {
+						error(e->token, "Objective-C method implementations may return at most 1 value");
 					} else {
 
-	                    auto method = ObjcMethodData{ ac, e };
+						auto method = ObjcMethodData{ ac, e };
 						method.ac.objc_selector = ac.objc_selector != "" ? ac.objc_selector : ac.objc_name;
 
 						CheckerInfo *info = ctx->info;
@@ -1033,6 +1055,8 @@ gb_internal void check_objc_methods(CheckerContext *ctx, Entity *e, AttributeCon
 							map_set(&info->objc_method_implementations, t, list);
 						}
 					}
+				} else if (ac.objc_selector != "") {
+					error(e->token, "@(objc_selector) may only be applied to procedures that are Objective-C implementations.");
 				}
 
 				mutex_lock(&global_type_name_objc_metadata_mutex);

src/checker.cpp

@@ -3352,7 +3352,7 @@ gb_internal DECL_ATTRIBUTE_PROC(proc_decl_attribute) {
 		ac->test = true;
 		return true;
 	} else if (name == "export") {
-		if (ac->objc_is_implementation) {
+		if (ac->objc_is_implementation) { // TODO(harold): Remove from here, this needs to be checked after all attributes are set.
 			error(value, "Setting @(export) explicitly is not allowed when @(objc_implement) is set. It is exported implicitly.");
 			return false;
 		}
@@ -3369,7 +3369,7 @@ gb_internal DECL_ATTRIBUTE_PROC(proc_decl_attribute) {
 		return true;
 	} else if (name == "linkage") {
 
-		if (ac->objc_is_implementation) {
+		if (ac->objc_is_implementation) {	// TODO(harold): Remove from here, this needs to be checked after all attributes are set.
 			error(value, "Explicit linkage not allowed when @(objc_implement) is set. It is set implicitly");
 			return false;
 		}
@@ -3684,6 +3684,10 @@ gb_internal DECL_ATTRIBUTE_PROC(proc_decl_attribute) {
 		ExactValue ev = check_decl_attribute_value(c, value);
 		if (ev.kind == ExactValue_Bool) {
 			ac->objc_is_implementation = ev.value_bool;
+
+			if (!ac->objc_is_implementation) {
+				ac->objc_is_disabled_implement = true;
+			}
 		} else if (ev.kind == ExactValue_Invalid) {
 			ac->objc_is_implementation = true;
 		} else {
@@ -3970,7 +3974,7 @@ gb_internal DECL_ATTRIBUTE_PROC(type_decl_attribute) {
 	} else if (name == "objc_ivar") {
 		Type *objc_ivar = check_type(c, value);
 
-		if (objc_ivar != nullptr) {
+		if (objc_ivar != nullptr && objc_ivar->kind == Type_Named) {
 			ac->objc_ivar = objc_ivar;
 		} else {
 			error(value, "'%.*s' expected a named type", LIT(name));
@@ -6488,36 +6492,33 @@ gb_internal void check_objc_context_provider_procedures(Checker *c) {
 		Entity *proc_entity = e->TypeName.objc_context_provider;
 		GB_ASSERT(proc_entity->kind == Entity_Procedure);
 
-		Type *proc_type = proc_entity->type;
+		auto &proc = proc_entity->type->Proc;
 
-		// TODO(harold): Give better errors here (specify exactly what's wrong)
-		const char *signature_error = "The procedure for @(objc_context_provider) has an incorrect signature.";
-
-		if (proc_type->Proc.param_count != 1 || proc_type->Proc.result_count != 1) {
-			error(proc_entity->token, signature_error);
-		} else {
-			Type *self_param  = base_type(proc_type->Proc.params->Tuple.variables[0]->type);
-			Type *return_type = base_named_type(proc_type->Proc.results->Tuple.variables[0]->type);
+		Type *return_type = proc.result_count != 1 ? t_untyped_nil : base_named_type(proc.results->Tuple.variables[0]->type);
+		if (return_type != t_context) {
+			error(proc_entity->token, "The @(objc_context_provider) procedure must only return a context.");
+		}
 
-			if (self_param->kind != Type_Pointer) {
-				error(proc_entity->token, signature_error);
-				continue;
-			}
+		const char *self_param_err = "The @(objc_context_provider) procedure must take as a parameter a single pointer to the @(objc_type) value.";
+		if (proc.param_count != 1) {
+			error(proc_entity->token, self_param_err);
+		}
 
-			self_param = base_named_type(self_param->Pointer.elem);
+		Type *self_param = base_type(proc.params->Tuple.variables[0]->type);
+		if (self_param->kind == Type_Pointer) {
+			error(proc_entity->token, self_param_err);
+		}
 
-			if (return_type != t_context) {
-				error(e->token, signature_error);
-			} else if (!internal_check_is_assignable_to(self_param, e->type) &&
-				(e->TypeName.objc_ivar && !internal_check_is_assignable_to(self_param, e->TypeName.objc_ivar))
-			) {
-				error(e->token, signature_error);
-			} else if (proc_type->Proc.calling_convention != ProcCC_CDecl &&
-					   proc_type->Proc.calling_convention != ProcCC_Contextless) {
-				error(e->token, signature_error);
-			} else if (proc_type->Proc.is_polymorphic) {
-				error(e->token, signature_error);
-		   	}
+		Type *self_type = base_named_type(self_param->Pointer.elem);
+		if (!internal_check_is_assignable_to(self_type, e->type) &&
+			!(e->TypeName.objc_ivar && internal_check_is_assignable_to(self_type, e->TypeName.objc_ivar))) {
+			error(proc_entity->token, self_param_err);
+		}
+		if (proc.calling_convention != ProcCC_CDecl && proc.calling_convention != ProcCC_Contextless) {
+			error(e->token, self_param_err);
+		}
+		if (proc.is_polymorphic) {
+			error(e->token, self_param_err);
 		}
 	}
 }

src/checker.hpp

@@ -154,7 +154,8 @@ struct AttributeContext {
 	Type *  objc_ivar;
 	Entity *objc_context_provider;
 	bool    objc_is_class_method;
-	bool    objc_is_implementation; // This struct or proc provides a class/method implementation, not a binding to an existing type.
+	bool    objc_is_implementation;     // This struct or proc provides a class/method implementation, not a binding to an existing type.
+	bool    objc_is_disabled_implement; // This means the method explicitly set @objc_implement to false so it won't be inferred from the class' attribute.
 
 	String require_target_feature; // required by the target micro-architecture
 	String enable_target_feature;  // will be enabled for the procedure only

src/checker_builtin_procs.hpp

@@ -674,7 +674,7 @@ gb_global BuiltinProc builtin_procs[BuiltinProc_COUNT] = {
 	{STR_LIT("objc_find_class"),        1, false, Expr_Expr, BuiltinProcPkg_intrinsics},
 	{STR_LIT("objc_register_selector"), 1, false, Expr_Expr, BuiltinProcPkg_intrinsics, false, true},
 	{STR_LIT("objc_register_class"),    1, false, Expr_Expr, BuiltinProcPkg_intrinsics, false, true},
-	{STR_LIT("objc_ivar_get"),          2, false, Expr_Expr, BuiltinProcPkg_intrinsics, false, true},
+	{STR_LIT("objc_ivar_get"),          1, false, Expr_Expr, BuiltinProcPkg_intrinsics, false, true},
 
 	{STR_LIT("constant_utf16_cstring"), 1, false, Expr_Expr, BuiltinProcPkg_intrinsics},