py: Add built-in super.

py/compile.c

@@ -61,6 +61,8 @@ typedef struct _compiler_t {
     int param_pass_num_dict_params;
     int param_pass_num_default_params;
 
+    bool func_arg_is_super; // used to compile special case of super() function call
+
     scope_t *scope_head;
     scope_t *scope_cur;
 
@@ -959,6 +961,7 @@ void compile_decorated(compiler_t *comp, mp_parse_node_struct_t *pns) {
             // nodes[1] contains arguments to the decorator function, if any
             if (!MP_PARSE_NODE_IS_NULL(pns_decorator->nodes[1])) {
                 // call the decorator function with the arguments in nodes[1]
+                comp->func_arg_is_super = false;
                 compile_node(comp, pns_decorator->nodes[1]);
             }
         }
@@ -2062,9 +2065,38 @@ void compile_factor_2(compiler_t *comp, mp_parse_node_struct_t *pns) {
     }
 }
 
+void compile_power(compiler_t *comp, mp_parse_node_struct_t *pns) {
+    // this is to handle special super() call
+    comp->func_arg_is_super = MP_PARSE_NODE_IS_ID(pns->nodes[0]) && MP_PARSE_NODE_LEAF_ARG(pns->nodes[0]) == MP_QSTR_super;
+
+    compile_generic_all_nodes(comp, pns);
+}
+
 void compile_trailer_paren_helper(compiler_t *comp, mp_parse_node_struct_t *pns, bool is_method_call) {
     // function to call is on top of stack
 
+#if !MICROPY_EMIT_CPYTHON
+    // this is to handle special super() call
+    if (MP_PARSE_NODE_IS_NULL(pns->nodes[0]) && comp->func_arg_is_super && comp->scope_cur->kind == SCOPE_FUNCTION) {
+        EMIT_ARG(load_id, MP_QSTR___class__);
+        // get first argument to function
+        bool found = false;
+        for (int i = 0; i < comp->scope_cur->id_info_len; i++) {
+            if (comp->scope_cur->id_info[i].param) {
+                EMIT_ARG(load_fast, MP_QSTR_, comp->scope_cur->id_info[i].local_num);
+                found = true;
+                break;
+            }
+        }
+        if (!found) {
+            printf("TypeError: super() call cannot find self\n");
+            return;
+        }
+        EMIT_ARG(call_function, 2, 0, false, false);
+        return;
+    }
+#endif
+
     int old_n_arg_keyword = comp->n_arg_keyword;
     bool old_have_star_arg = comp->have_star_arg;
     bool old_have_dbl_star_arg = comp->have_dbl_star_arg;
@@ -2107,6 +2139,7 @@ void compile_power_trailers(compiler_t *comp, mp_parse_node_struct_t *pns) {
         } else {
             compile_node(comp, pns->nodes[i]);
         }
+        comp->func_arg_is_super = false;
     }
 }
 
@@ -2836,7 +2869,7 @@ void compile_scope(compiler_t *comp, scope_t *scope, pass_kind_t pass) {
 #if MICROPY_EMIT_CPYTHON
             EMIT_ARG(load_closure, MP_QSTR___class__, 0); // XXX check this is the correct local num
 #else
-            EMIT_ARG(load_fast, MP_QSTR___class__, 0); // XXX check this is the correct local num
+            EMIT_ARG(load_fast, MP_QSTR___class__, id->local_num);
 #endif
         }
         EMIT(return_value);
@@ -3044,6 +3077,8 @@ mp_obj_t mp_compile(mp_parse_node_t pn, qstr source_file, bool is_repl) {
     comp->break_continue_except_level = 0;
     comp->cur_except_level = 0;
 
+    comp->func_arg_is_super = false;
+
     comp->scope_head = NULL;
     comp->scope_cur = NULL;
 
@@ -3054,7 +3089,7 @@ mp_obj_t mp_compile(mp_parse_node_t pn, qstr source_file, bool is_repl) {
     scope_t *module_scope = scope_new_and_link(comp, SCOPE_MODULE, pn, EMIT_OPT_NONE);
 
     // compile pass 1
-    comp->emit = emit_pass1_new(MP_QSTR___class__);
+    comp->emit = emit_pass1_new();
     comp->emit_method_table = &emit_pass1_method_table;
     comp->emit_inline_asm = NULL;
     comp->emit_inline_asm_method_table = NULL;

py/emit.h

@@ -117,7 +117,7 @@ extern const emit_method_table_t emit_bc_method_table;
 extern const emit_method_table_t emit_native_x64_method_table;
 extern const emit_method_table_t emit_native_thumb_method_table;
 
-emit_t *emit_pass1_new(qstr qstr___class__);
+emit_t *emit_pass1_new(void);
 emit_t *emit_cpython_new(uint max_num_labels);
 emit_t *emit_bc_new(uint max_num_labels);
 emit_t *emit_native_x64_new(uint max_num_labels);

py/emitpass1.c

@@ -15,13 +15,11 @@
 #include "emit.h"
 
 struct _emit_t {
-    qstr qstr___class__;
     scope_t *scope;
 };
 
-emit_t *emit_pass1_new(qstr qstr___class__) {
+emit_t *emit_pass1_new(void) {
     emit_t *emit = m_new(emit_t, 1);
-    emit->qstr___class__ = qstr___class__;
     return emit;
 }
 
@@ -45,18 +43,21 @@ static void emit_pass1_load_id(emit_t *emit, qstr qstr) {
     bool added;
     id_info_t *id = scope_find_or_add_id(emit->scope, qstr, &added);
     if (added) {
-        if (strcmp(qstr_str(qstr), "super") == 0 && emit->scope->kind == SCOPE_FUNCTION) {
+#if MICROPY_EMIT_CPYTHON
+        if (qstr == MP_QSTR_super && emit->scope->kind == SCOPE_FUNCTION) {
             // special case, super is a global, and also counts as use of __class__
             id->kind = ID_INFO_KIND_GLOBAL_EXPLICIT;
-            id_info_t *id2 = scope_find_local_in_parent(emit->scope, emit->qstr___class__);
+            id_info_t *id2 = scope_find_local_in_parent(emit->scope, MP_QSTR___class__);
             if (id2 != NULL) {
-                id2 = scope_find_or_add_id(emit->scope, emit->qstr___class__, &added);
+                id2 = scope_find_or_add_id(emit->scope, MP_QSTR___class__, &added);
                 if (added) {
                     id2->kind = ID_INFO_KIND_FREE;
-                    scope_close_over_in_parents(emit->scope, emit->qstr___class__);
+                    scope_close_over_in_parents(emit->scope, MP_QSTR___class__);
                 }
             }
-        } else {
+        } else
+#endif
+        {
             id_info_t *id2 = scope_find_local_in_parent(emit->scope, qstr);
             if (id2 != NULL && (id2->kind == ID_INFO_KIND_LOCAL || id2->kind == ID_INFO_KIND_CELL || id2->kind == ID_INFO_KIND_FREE)) {
                 id->kind = ID_INFO_KIND_FREE;

py/grammar.h

@@ -214,7 +214,7 @@ DEF_RULE(term_op, nc, or(4), tok(OP_STAR), tok(OP_SLASH), tok(OP_PERCENT), tok(O
 DEF_RULE(factor, nc, or(2), rule(factor_2), rule(power))
 DEF_RULE(factor_2, c(factor_2), and(2), rule(factor_op), rule(factor))
 DEF_RULE(factor_op, nc, or(3), tok(OP_PLUS), tok(OP_MINUS), tok(OP_TILDE))
-DEF_RULE(power, c(generic_all_nodes), and(3), rule(atom), opt_rule(power_trailers), opt_rule(power_dbl_star))
+DEF_RULE(power, c(power), and(3), rule(atom), opt_rule(power_trailers), opt_rule(power_dbl_star))
 DEF_RULE(power_trailers, c(power_trailers), one_or_more, rule(trailer))
 DEF_RULE(power_dbl_star, c(power_dbl_star), and(2), tok(OP_DBL_STAR), rule(factor))
 

py/obj.h

@@ -231,6 +231,7 @@ mp_obj_t mp_obj_new_list(uint n, mp_obj_t *items);
 mp_obj_t mp_obj_new_dict(int n_args);
 mp_obj_t mp_obj_new_set(int n_args, mp_obj_t *items);
 mp_obj_t mp_obj_new_slice(mp_obj_t start, mp_obj_t stop, mp_obj_t step);
+mp_obj_t mp_obj_new_super(mp_obj_t type, mp_obj_t obj);
 mp_obj_t mp_obj_new_bound_meth(mp_obj_t meth, mp_obj_t self);
 mp_obj_t mp_obj_new_getitem_iter(mp_obj_t *args);
 mp_obj_t mp_obj_new_module(qstr module_name);
@@ -371,6 +372,9 @@ void mp_obj_fun_bc_get(mp_obj_t self_in, int *n_args, uint *n_state, const byte
 
 mp_obj_t mp_identity(mp_obj_t self);
 
+// super
+extern const mp_obj_type_t super_type;
+
 // generator
 extern const mp_obj_type_t gen_instance_type;
 

py/objtype.c

@@ -362,6 +362,96 @@ mp_obj_t mp_obj_new_type(const char *name, mp_obj_t bases_tuple, mp_obj_t locals
     return o;
 }
 
+/******************************************************************************/
+// super object
+
+typedef struct _mp_obj_super_t {
+    mp_obj_base_t base;
+    mp_obj_t type;
+    mp_obj_t obj;
+} mp_obj_super_t;
+
+static void super_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
+    mp_obj_super_t *self = self_in;
+    print(env, "<super: ");
+    mp_obj_print_helper(print, env, self->type, PRINT_STR);
+    print(env, ", ");
+    mp_obj_print_helper(print, env, self->obj, PRINT_STR);
+    print(env, ">");
+}
+
+static mp_obj_t super_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
+    if (n_args != 2 || n_kw != 0) {
+        // 0 arguments are turned into 2 in the compiler
+        // 1 argument is not yet implemented
+        nlr_jump(mp_obj_new_exception_msg(MP_QSTR_TypeError, "super() requires 2 arguments"));
+    }
+    return mp_obj_new_super(args[0], args[1]);
+}
+
+// for fail, do nothing; for attr, dest[0] = value; for method, dest[0] = method, dest[1] = self
+static void super_load_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
+    assert(MP_OBJ_IS_TYPE(self_in, &super_type));
+    mp_obj_super_t *self = self_in;
+
+    assert(MP_OBJ_IS_TYPE(self->type, &mp_const_type));
+
+    mp_obj_type_t *type = self->type;
+
+    // for a const struct, this entry might be NULL
+    if (type->bases_tuple == MP_OBJ_NULL) {
+        return;
+    }
+
+    uint len;
+    mp_obj_t *items;
+    mp_obj_tuple_get(type->bases_tuple, &len, &items);
+    for (uint i = 0; i < len; i++) {
+        assert(MP_OBJ_IS_TYPE(items[i], &mp_const_type));
+        mp_obj_t member = mp_obj_class_lookup((mp_obj_type_t*)items[i], attr);
+        if (member != MP_OBJ_NULL) {
+            // XXX this and the code in class_load_attr need to be factored out
+            if (mp_obj_is_callable(member)) {
+                // class member is callable so build a bound method
+                // check if the methods are functions, static or class methods
+                // see http://docs.python.org/3.3/howto/descriptor.html
+                // TODO check that this is the correct place to have this logic
+                if (MP_OBJ_IS_TYPE(member, &mp_type_staticmethod)) {
+                    // return just the function
+                    dest[0] = ((mp_obj_staticmethod_t*)member)->fun;
+                } else if (MP_OBJ_IS_TYPE(member, &mp_type_classmethod)) {
+                    // return a bound method, with self being the type of this object
+                    dest[0] = ((mp_obj_classmethod_t*)member)->fun;
+                    dest[1] = mp_obj_get_type(self->obj);
+                } else {
+                    // return a bound method, with self being this object
+                    dest[0] = member;
+                    dest[1] = self->obj;
+                }
+                return;
+            } else {
+                // class member is a value, so just return that value
+                dest[0] = member;
+                return;
+            }
+        }
+    }
+}
+
+const mp_obj_type_t super_type = {
+    { &mp_const_type },
+    "super",
+    .print = super_print,
+    .make_new = super_make_new,
+    .load_attr = super_load_attr,
+};
+
+mp_obj_t mp_obj_new_super(mp_obj_t type, mp_obj_t obj) {
+    mp_obj_super_t *o = m_new_obj(mp_obj_super_t);
+    *o = (mp_obj_super_t){{&super_type}, type, obj};
+    return o;
+}
+
 /******************************************************************************/
 // built-ins specific to types
 

py/qstrdefs.h

@@ -80,6 +80,7 @@ Q(repr)
 Q(set)
 Q(sorted)
 Q(sum)
+Q(super)
 Q(str)
 Q(sys)
 Q(tuple)

py/runtime.c

@@ -129,6 +129,7 @@ void rt_init(void) {
     mp_map_add_qstr(&map_builtins, MP_QSTR_list, (mp_obj_t)&list_type);
     mp_map_add_qstr(&map_builtins, MP_QSTR_map, (mp_obj_t)&map_type);
     mp_map_add_qstr(&map_builtins, MP_QSTR_set, (mp_obj_t)&set_type);
+    mp_map_add_qstr(&map_builtins, MP_QSTR_super, (mp_obj_t)&super_type);
     mp_map_add_qstr(&map_builtins, MP_QSTR_tuple, (mp_obj_t)&tuple_type);
     mp_map_add_qstr(&map_builtins, MP_QSTR_type, (mp_obj_t)&mp_const_type);
     mp_map_add_qstr(&map_builtins, MP_QSTR_zip, (mp_obj_t)&zip_type);
@@ -852,7 +853,10 @@ static void rt_load_method_maybe(mp_obj_t base, qstr attr, mp_obj_t *dest) {
 
     // if nothing found yet, look for built-in and generic names
     if (dest[0] == MP_OBJ_NULL) {
-        if (attr == MP_QSTR___next__ && type->iternext != NULL) {
+        if (attr == MP_QSTR___class__) {
+            // a.__class__ is equivalent to type(a)
+            dest[0] = type;
+        } else if (attr == MP_QSTR___next__ && type->iternext != NULL) {
             dest[0] = (mp_obj_t)&mp_builtin_next_obj;
             dest[1] = base;
         } else if (type->load_attr == NULL) {

tests/bytecode/mp-tests/class6.py

@@ -0,0 +1,7 @@
+class A:
+    def f(self):
+        pass
+
+class B(A):
+    def f(self):
+        super().f()

tests/bytecode/mp-tests/class7.py

@@ -0,0 +1,6 @@
+# accessing super, but not as a function call
+
+class A:
+    def f():
+        #x = super
+        print(super)