add `@dataclass`

docs/modules/dataclasses.md

@@ -0,0 +1,14 @@
+---
+icon: package
+label: dataclasses
+---
+
+### `dataclasses.dataclass`
+
+A decorator that is used to add generated special method to classes, including `__init__`, `__repr__` and `__eq__`.
+
+### `dataclasses.asdict(obj) -> dict`
+
+Convert a dataclass instance to a dictionary.
+
+

include/pocketpy/cffi.h

@@ -22,6 +22,7 @@ namespace pkpy {
             throw std::runtime_error(msg.str());                            \
         }                                                                   \
         PyObject* type = vm->new_type_object(mod, #name, base);             \
+        mod->attr().set(#name, type);                                       \
         T::_register(vm, mod, type);                                        \
         return type;                                                        \
     }                                                                       

include/pocketpy/common.h

@@ -23,7 +23,7 @@
 #include <bitset>
 #include <deque>
 
-#define PK_VERSION				"1.3.3"
+#define PK_VERSION				"1.3.5"
 
 #include "config.h"
 #include "export.h"
@@ -166,7 +166,7 @@ static_assert(sizeof(Number::int_t) == sizeof(void*));
 static_assert(sizeof(BitsCvt) == sizeof(void*));
 static_assert(std::numeric_limits<f64>::is_iec559);
 
-struct Dummy { };
+struct Dummy { }; // for special objects: True, False, None, Ellipsis, etc.
 struct DummyInstance { };
 struct DummyModule { };
 struct NoReturn { };

include/pocketpy/compiler.h

@@ -118,7 +118,8 @@ class Compiler {
     bool try_compile_assignment();
     void compile_stmt();
     void consume_type_hints();
-    void compile_class();
+    void _add_decorators(const std::vector<Expr_>& decorators);
+    void compile_class(const std::vector<Expr_>& decorators={});
     void _compile_f_args(FuncDecl_ decl, bool enable_type_hints);
     void compile_function(const std::vector<Expr_>& decorators={});
 

include/pocketpy/opcodes.h

@@ -118,6 +118,9 @@ OPCODE(UNPACK_EX)
 OPCODE(BEGIN_CLASS)
 OPCODE(END_CLASS)
 OPCODE(STORE_CLASS_ATTR)
+OPCODE(BEGIN_CLASS_DECORATION)
+OPCODE(END_CLASS_DECORATION)
+OPCODE(ADD_CLASS_ANNOTATION)
 /**************************/
 OPCODE(WITH_ENTER)
 OPCODE(WITH_EXIT)

include/pocketpy/vm.h

@@ -55,6 +55,8 @@ struct PyTypeInfo{
     Str name;
     bool subclass_enabled;
 
+    std::vector<StrName> annotated_fields;
+
     // cached special methods
     // unary operators
     PyObject* (*m__repr__)(VM* vm, PyObject*) = nullptr;

python/builtins.py

@@ -5,6 +5,17 @@ def print(*args, sep=' ', end='\n'):
     s = sep.join([str(i) for i in args])
     _sys.stdout.write(s + end)
 
+def issubclass(cls, base):
+    if type(cls) is not type:
+        raise TypeError('issubclass() arg 1 must be a class')
+    if type(base) is not type:
+        raise TypeError('issubclass() arg 2 must be a class')
+    while cls is not None:
+        if cls is base:
+            return True
+        cls = cls.__base__
+    return False
+
 def _minmax_reduce(op, args, key):
     if key is None: 
         if len(args) == 2:

python/dataclasses.py

@@ -0,0 +1,59 @@
+def _wrapped__init__(self, *args, **kwargs):
+    cls = type(self)
+    cls_d = cls.__dict__
+    fields: tuple[str] = cls.__annotations__
+    i = 0   # index into args
+    for field in fields:
+        if field in kwargs:
+            setattr(self, field, kwargs.pop(field))
+        else:
+            if i < len(args):
+                setattr(self, field, args[i])
+                ++i
+            elif field in cls_d:    # has default value
+                setattr(self, field, cls_d[field])
+            else:
+                raise TypeError(f"{cls.__name__} missing required argument {field!r}")
+    if len(args) > i:
+        raise TypeError(f"{cls.__name__} takes {len(field)} positional arguments but {len(args)} were given")
+    if len(kwargs) > 0:
+        raise TypeError(f"{cls.__name__} got an unexpected keyword argument {next(iter(kwargs))!r}")
+
+def _wrapped__repr__(self):
+    fields: tuple[str] = type(self).__annotations__
+    obj_d = self.__dict__
+    args: list = [f"{field}={obj_d[field]!r}" for field in fields]
+    return f"{type(self).__name__}({', '.join(args)})"
+
+def _wrapped__eq__(self, other):
+    if type(self) is not type(other):
+        return False
+    fields: tuple[str] = type(self).__annotations__
+    for field in fields:
+        if getattr(self, field) != getattr(other, field):
+            return False
+    return True
+
+def dataclass(cls: type):
+    assert type(cls) is type
+    cls_d = cls.__dict__
+    if '__init__' not in cls_d:
+        cls.__init__ = _wrapped__init__
+    if '__repr__' not in cls_d:
+        cls.__repr__ = _wrapped__repr__
+    if '__eq__' not in cls_d:
+        cls.__eq__ = _wrapped__eq__
+    fields: tuple[str] = cls.__annotations__
+    has_default = False
+    for field in fields:
+        if field in cls_d:
+            has_default = True
+        else:
+            if has_default:
+                raise TypeError(f"non-default argument {field!r} follows default argument")
+    return cls
+
+def asdict(obj) -> dict:
+    fields: tuple[str] = type(obj).__annotations__
+    obj_d = obj.__dict__
+    return {field: obj_d[field] for field in fields}

src/ceval.cpp

@@ -749,6 +749,8 @@ __NEXT_STEP:;
     } DISPATCH();
     TARGET(END_CLASS) {
         PK_ASSERT(_curr_class != nullptr);
+        StrName _name(byte.arg);
+        frame->_module->attr().set(_name, _curr_class);
         _curr_class = nullptr;
     } DISPATCH();
     TARGET(STORE_CLASS_ATTR){
@@ -760,6 +762,18 @@ __NEXT_STEP:;
         }
         _curr_class->attr().set(_name, _0);
     } DISPATCH();
+    TARGET(BEGIN_CLASS_DECORATION){
+        PUSH(_curr_class);
+    } DISPATCH();
+    TARGET(END_CLASS_DECORATION){
+        _curr_class = POPX();
+    } DISPATCH();
+    TARGET(ADD_CLASS_ANNOTATION) {
+        PK_ASSERT(_curr_class != nullptr);
+        StrName _name(byte.arg);
+        Type type = PK_OBJ_GET(Type, _curr_class);
+        _type_info(type)->annotated_fields.push_back(_name);
+    } DISPATCH();
     /*****************************************/
     TARGET(WITH_ENTER)
         call_method(POPX(), __enter__);
@@ -818,8 +832,8 @@ __NEXT_STEP:;
     } DISPATCH();
 
 #if !PK_ENABLE_COMPUTED_GOTO
-        static_assert(OP_DEC_GLOBAL == 107);
-        case 108: case 109: case 110: case 111: case 112: case 113: case 114: case 115: case 116: case 117: case 118: case 119: case 120: case 121: case 122: case 123: case 124: case 125: case 126: case 127: case 128: case 129: case 130: case 131: case 132: case 133: case 134: case 135: case 136: case 137: case 138: case 139: case 140: case 141: case 142: case 143: case 144: case 145: case 146: case 147: case 148: case 149: case 150: case 151: case 152: case 153: case 154: case 155: case 156: case 157: case 158: case 159: case 160: case 161: case 162: case 163: case 164: case 165: case 166: case 167: case 168: case 169: case 170: case 171: case 172: case 173: case 174: case 175: case 176: case 177: case 178: case 179: case 180: case 181: case 182: case 183: case 184: case 185: case 186: case 187: case 188: case 189: case 190: case 191: case 192: case 193: case 194: case 195: case 196: case 197: case 198: case 199: case 200: case 201: case 202: case 203: case 204: case 205: case 206: case 207: case 208: case 209: case 210: case 211: case 212: case 213: case 214: case 215: case 216: case 217: case 218: case 219: case 220: case 221: case 222: case 223: case 224: case 225: case 226: case 227: case 228: case 229: case 230: case 231: case 232: case 233: case 234: case 235: case 236: case 237: case 238: case 239: case 240: case 241: case 242: case 243: case 244: case 245: case 246: case 247: case 248: case 249: case 250: case 251: case 252: case 253: case 254: case 255: FATAL_ERROR(); break;
+        static_assert(OP_DEC_GLOBAL == 110);
+        case 111: case 112: case 113: case 114: case 115: case 116: case 117: case 118: case 119: case 120: case 121: case 122: case 123: case 124: case 125: case 126: case 127: case 128: case 129: case 130: case 131: case 132: case 133: case 134: case 135: case 136: case 137: case 138: case 139: case 140: case 141: case 142: case 143: case 144: case 145: case 146: case 147: case 148: case 149: case 150: case 151: case 152: case 153: case 154: case 155: case 156: case 157: case 158: case 159: case 160: case 161: case 162: case 163: case 164: case 165: case 166: case 167: case 168: case 169: case 170: case 171: case 172: case 173: case 174: case 175: case 176: case 177: case 178: case 179: case 180: case 181: case 182: case 183: case 184: case 185: case 186: case 187: case 188: case 189: case 190: case 191: case 192: case 193: case 194: case 195: case 196: case 197: case 198: case 199: case 200: case 201: case 202: case 203: case 204: case 205: case 206: case 207: case 208: case 209: case 210: case 211: case 212: case 213: case 214: case 215: case 216: case 217: case 218: case 219: case 220: case 221: case 222: case 223: case 224: case 225: case 226: case 227: case 228: case 229: case 230: case 231: case 232: case 233: case 234: case 235: case 236: case 237: case 238: case 239: case 240: case 241: case 242: case 243: case 244: case 245: case 246: case 247: case 248: case 249: case 250: case 251: case 252: case 253: case 254: case 255: FATAL_ERROR(); break;
     }
 #endif
 }

src/cffi.cpp

@@ -164,11 +164,12 @@ void add_module_c(VM* vm){
     Type type_t;
 
 #define BIND_PRIMITIVE(T, CNAME) \
-    vm->bind_func<1>(mod, CNAME "_", [](VM* vm, ArgsView args){        \
+    vm->bind_func<1>(mod, CNAME "_", [](VM* vm, ArgsView args){         \
         T val = CAST(T, args[0]);                                       \
         return VAR_T(C99Struct, &val, sizeof(T));                       \
     });                                                                 \
-    type = vm->new_type_object(mod, CNAME "_p", VoidP::_type(vm));     \
+    type = vm->new_type_object(mod, CNAME "_p", VoidP::_type(vm));      \
+    mod->attr().set(CNAME "_p", type);                                  \
     type_t = PK_OBJ_GET(Type, type);                                    \
     vm->bind_method<0>(type, "read", [](VM* vm, ArgsView args){         \
         VoidP& voidp = PK_OBJ_GET(VoidP, args[0]);                      \

src/compiler.cpp

@@ -712,8 +712,13 @@ __EAT_DOTS_END:
             decorators.push_back(ctx()->s_expr.popx());
             if(!match_newlines_repl()) SyntaxError();
         }while(match(TK("@")));
-        consume(TK("def"));
-        compile_function(decorators);
+
+        if(match(TK("class"))){
+            compile_class(decorators);
+        }else{
+            consume(TK("def"));
+            compile_function(decorators);
+        }
     }
 
     bool Compiler::try_compile_assignment(){
@@ -927,6 +932,12 @@ __EAT_DOTS_END:
                     if(match(TK(":"))){
                         consume_type_hints();
                         is_typed_name = true;
+
+                        if(ctx()->is_compiling_class){
+                            // add to __annotations__
+                            NameExpr* ne = static_cast<NameExpr*>(ctx()->s_expr.top().get());
+                            ctx()->emit_(OP_ADD_CLASS_ANNOTATION, ne->name.index, BC_KEEPLINE);
+                        }
                     }
                 }
                 if(!try_compile_assignment()){
@@ -955,7 +966,18 @@ __EAT_DOTS_END:
         ctx()->s_expr.pop();
     }
 
-    void Compiler::compile_class(){
+    void Compiler::_add_decorators(const std::vector<Expr_>& decorators){
+        // [obj]
+        for(auto it=decorators.rbegin(); it!=decorators.rend(); ++it){
+            (*it)->emit_(ctx());                                    // [obj, f]
+            ctx()->emit_(OP_ROT_TWO, BC_NOARG, (*it)->line);        // [f, obj]
+            ctx()->emit_(OP_LOAD_NULL, BC_NOARG, BC_KEEPLINE);      // [f, obj, NULL]
+            ctx()->emit_(OP_ROT_TWO, BC_NOARG, BC_KEEPLINE);        // [obj, NULL, f]
+            ctx()->emit_(OP_CALL, 1, (*it)->line);                  // [obj]
+        }
+    }
+
+    void Compiler::compile_class(const std::vector<Expr_>& decorators){
         consume(TK("@id"));
         int namei = StrName(prev().sv()).index;
         Expr_ base = nullptr;
@@ -981,7 +1003,14 @@ __EAT_DOTS_END:
         ctx()->is_compiling_class = true;
         compile_block_body();
         ctx()->is_compiling_class = false;
-        ctx()->emit_(OP_END_CLASS, BC_NOARG, BC_KEEPLINE);
+
+        if(!decorators.empty()){
+            ctx()->emit_(OP_BEGIN_CLASS_DECORATION, BC_NOARG, BC_KEEPLINE);
+            _add_decorators(decorators);
+            ctx()->emit_(OP_END_CLASS_DECORATION, BC_NOARG, BC_KEEPLINE);
+        }
+
+        ctx()->emit_(OP_END_CLASS, namei, BC_KEEPLINE);
     }
 
     void Compiler::_compile_f_args(FuncDecl_ decl, bool enable_type_hints){
@@ -1077,14 +1106,8 @@ __EAT_DOTS_END:
         }
         ctx()->emit_(OP_LOAD_FUNCTION, ctx()->add_func_decl(decl), prev().line);
 
-        // add decorators
-        for(auto it=decorators.rbegin(); it!=decorators.rend(); ++it){
-            (*it)->emit_(ctx());
-            ctx()->emit_(OP_ROT_TWO, BC_NOARG, (*it)->line);
-            ctx()->emit_(OP_LOAD_NULL, BC_NOARG, BC_KEEPLINE);
-            ctx()->emit_(OP_ROT_TWO, BC_NOARG, BC_KEEPLINE);
-            ctx()->emit_(OP_CALL, 1, (*it)->line);
-        }
+        _add_decorators(decorators);
+
         if(!ctx()->is_compiling_class){
             auto e = make_expr<NameExpr>(decl_name, name_scope());
             e->emit_store(ctx());

src/pocketpy.cpp

@@ -1146,29 +1146,6 @@ void init_builtins(VM* _vm) {
         return value;
     });
 
-    // _vm->bind_method<0>("dict", "_data", [](VM* vm, ArgsView args) {
-    //     Dict& self = _CAST(Dict&, args[0]);
-    //     SStream ss;
-    //     ss << "[\n";
-    //     for(int i=0; i<self._capacity; i++){
-    //         auto item = self._items[i];
-    //         Str key("None");
-    //         Str value("None");
-    //         if(item.first != nullptr){
-    //             key = CAST(Str&, vm->py_repr(item.first));
-    //         }
-    //         if(item.second != nullptr){
-    //             value = CAST(Str&, vm->py_repr(item.second));
-    //         }
-    //         int prev = self._nodes[i].prev;
-    //         int next = self._nodes[i].next;
-    //         ss << "  [" << key << ", " << value << ", " << prev << ", " << next << "],\n";
-    //     }
-    //     ss << "]\n";
-    //     vm->stdout_write(ss.str());
-    //     return vm->None;
-    // });
-
     _vm->bind__contains__(_vm->tp_dict, [](VM* vm, PyObject* obj, PyObject* key) {
         Dict& self = _CAST(Dict&, obj);
         return VAR(self.contains(key));
@@ -1615,6 +1592,15 @@ void VM::post_init(){
         return self;        // for generics
     });
 
+    bind_property(_t(tp_type), "__annotations__", [](VM* vm, ArgsView args){
+        PyTypeInfo* ti = vm->_type_info(PK_OBJ_GET(Type, args[0]));
+        Tuple t(ti->annotated_fields.size());
+        for(int i=0; i<ti->annotated_fields.size(); i++){
+            t[i] = VAR(ti->annotated_fields[i].sv());
+        }
+        return VAR(std::move(t));
+    });
+
     bind__repr__(tp_type, [](VM* vm, PyObject* self){
         SStream ss;
         const PyTypeInfo& info = vm->_all_types[PK_OBJ_GET(Type, self)];
@@ -1679,7 +1665,7 @@ void VM::post_init(){
     add_module_operator(this);
     add_module_csv(this);
 
-    for(const char* name: {"this", "functools", "heapq", "bisect", "pickle", "_long", "colorsys", "typing", "datetime"}){
+    for(const char* name: {"this", "functools", "heapq", "bisect", "pickle", "_long", "colorsys", "typing", "datetime", "dataclasses"}){
         _lazy_modules[name] = kPythonLibs[name];
     }
 

src/vm.cpp

@@ -204,7 +204,6 @@ namespace pkpy{
             name.sv(),
             subclass_enabled,
         };
-        if(mod != nullptr) mod->attr().set(name, obj);
         _all_types.push_back(info);
         return obj;
     }

tests/82_dataclasses.py

@@ -0,0 +1,29 @@
+from dataclasses import dataclass, asdict
+
+@dataclass
+class A:
+    x: int
+    y: str = '123'
+
+assert repr(A(1)) == "A(x=1, y='123')"
+assert repr(A(x=3)) == "A(x=3, y='123')"
+assert repr(A(1, '555')) == "A(x=1, y='555')"
+assert repr(A(x=7, y='555')) == "A(x=7, y='555')"
+
+assert asdict(A(1, '555')) == {'x': 1, 'y': '555'}
+
+assert A(1, 'N') == A(1, 'N')
+assert A(1, 'N') != A(1, 'M')
+
+def wrapped(cls):
+    return int
+
+@wrapped
+@wrapped
+@wrapped
+@wrapped
+class A:
+    def __init__(self) -> None:
+        pass
+
+assert A('123') == 123

tests/99_builtin_func.py

@@ -978,4 +978,13 @@ assert callable(isinstance) is True  # builtin function
 
 
 assert id(0) is None
-assert id(2**62) is not None
+assert id(2**62) is not None
+
+# test issubclass
+assert issubclass(int, int) is True
+assert issubclass(int, object) is True
+assert issubclass(object, int) is False
+assert issubclass(object, object) is True
+assert issubclass(int, type) is False
+assert issubclass(type, type) is True
+assert issubclass(float, int) is False