py: Implement getattr() builtin.

py/builtin.c

@@ -381,3 +381,10 @@ STATIC mp_obj_t mp_builtin_id(mp_obj_t o_in) {
 }
 
 MP_DEFINE_CONST_FUN_OBJ_1(mp_builtin_id_obj, mp_builtin_id);
+
+STATIC mp_obj_t mp_builtin_getattr(mp_obj_t o_in, mp_obj_t attr) {
+    assert(MP_OBJ_IS_QSTR(attr));
+    return rt_load_attr(o_in, MP_OBJ_QSTR_VALUE(attr));
+}
+
+MP_DEFINE_CONST_FUN_OBJ_2(mp_builtin_getattr_obj, mp_builtin_getattr);

py/builtin.h

@@ -12,6 +12,7 @@ MP_DECLARE_CONST_FUN_OBJ(mp_builtin_dir_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_builtin_divmod_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_builtin_eval_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_builtin_exec_obj);
+MP_DECLARE_CONST_FUN_OBJ(mp_builtin_getattr_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_builtin_hash_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_builtin_id_obj);
 MP_DECLARE_CONST_FUN_OBJ(mp_builtin_isinstance_obj);

py/builtintables.c

@@ -60,6 +60,7 @@ STATIC const mp_builtin_elem_t builtin_object_table[] = {
     { MP_QSTR_divmod, (mp_obj_t)&mp_builtin_divmod_obj },
     { MP_QSTR_eval, (mp_obj_t)&mp_builtin_eval_obj },
     { MP_QSTR_exec, (mp_obj_t)&mp_builtin_exec_obj },
+    { MP_QSTR_getattr, (mp_obj_t)&mp_builtin_getattr_obj },
     { MP_QSTR_hash, (mp_obj_t)&mp_builtin_hash_obj },
     { MP_QSTR_id, (mp_obj_t)&mp_builtin_id_obj },
     { MP_QSTR_isinstance, (mp_obj_t)&mp_builtin_isinstance_obj },

py/qstrdefs.h

@@ -92,6 +92,7 @@ Q(eval)
 Q(exec)
 Q(filter)
 Q(float)
+Q(getattr)
 Q(hash)
 Q(id)
 Q(int)

tests/basics/getattr1.py

+class A:
+
+    var = 132
+
+    def __init__(self):
+        self.var2 = 34
+
+    def meth(self, i):
+        return 42 + i
+
+
+a = A()
+print(getattr(a, "var"))
+print(getattr(a, "var2"))
+print(getattr(a, "meth")(5))