cpython/Parser/action_helpers.c

1694 lines
52 KiB
C

#include <Python.h>
#include "pegen.h"
#include "string_parser.h"
#include "pycore_runtime.h" // _PyRuntime
#include "pycore_pystate.h" // _PyInterpreterState_GET()
void *
_PyPegen_dummy_name(Parser *p, ...)
{
return &_PyRuntime.parser.dummy_name;
}
/* Creates a single-element asdl_seq* that contains a */
asdl_seq *
_PyPegen_singleton_seq(Parser *p, void *a)
{
assert(a != NULL);
asdl_seq *seq = (asdl_seq*)_Py_asdl_generic_seq_new(1, p->arena);
if (!seq) {
return NULL;
}
asdl_seq_SET_UNTYPED(seq, 0, a);
return seq;
}
/* Creates a copy of seq and prepends a to it */
asdl_seq *
_PyPegen_seq_insert_in_front(Parser *p, void *a, asdl_seq *seq)
{
assert(a != NULL);
if (!seq) {
return _PyPegen_singleton_seq(p, a);
}
asdl_seq *new_seq = (asdl_seq*)_Py_asdl_generic_seq_new(asdl_seq_LEN(seq) + 1, p->arena);
if (!new_seq) {
return NULL;
}
asdl_seq_SET_UNTYPED(new_seq, 0, a);
for (Py_ssize_t i = 1, l = asdl_seq_LEN(new_seq); i < l; i++) {
asdl_seq_SET_UNTYPED(new_seq, i, asdl_seq_GET_UNTYPED(seq, i - 1));
}
return new_seq;
}
/* Creates a copy of seq and appends a to it */
asdl_seq *
_PyPegen_seq_append_to_end(Parser *p, asdl_seq *seq, void *a)
{
assert(a != NULL);
if (!seq) {
return _PyPegen_singleton_seq(p, a);
}
asdl_seq *new_seq = (asdl_seq*)_Py_asdl_generic_seq_new(asdl_seq_LEN(seq) + 1, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0, l = asdl_seq_LEN(new_seq); i + 1 < l; i++) {
asdl_seq_SET_UNTYPED(new_seq, i, asdl_seq_GET_UNTYPED(seq, i));
}
asdl_seq_SET_UNTYPED(new_seq, asdl_seq_LEN(new_seq) - 1, a);
return new_seq;
}
static Py_ssize_t
_get_flattened_seq_size(asdl_seq *seqs)
{
Py_ssize_t size = 0;
for (Py_ssize_t i = 0, l = asdl_seq_LEN(seqs); i < l; i++) {
asdl_seq *inner_seq = asdl_seq_GET_UNTYPED(seqs, i);
size += asdl_seq_LEN(inner_seq);
}
return size;
}
/* Flattens an asdl_seq* of asdl_seq*s */
asdl_seq *
_PyPegen_seq_flatten(Parser *p, asdl_seq *seqs)
{
Py_ssize_t flattened_seq_size = _get_flattened_seq_size(seqs);
assert(flattened_seq_size > 0);
asdl_seq *flattened_seq = (asdl_seq*)_Py_asdl_generic_seq_new(flattened_seq_size, p->arena);
if (!flattened_seq) {
return NULL;
}
int flattened_seq_idx = 0;
for (Py_ssize_t i = 0, l = asdl_seq_LEN(seqs); i < l; i++) {
asdl_seq *inner_seq = asdl_seq_GET_UNTYPED(seqs, i);
for (Py_ssize_t j = 0, li = asdl_seq_LEN(inner_seq); j < li; j++) {
asdl_seq_SET_UNTYPED(flattened_seq, flattened_seq_idx++, asdl_seq_GET_UNTYPED(inner_seq, j));
}
}
assert(flattened_seq_idx == flattened_seq_size);
return flattened_seq;
}
void *
_PyPegen_seq_last_item(asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
return asdl_seq_GET_UNTYPED(seq, len - 1);
}
void *
_PyPegen_seq_first_item(asdl_seq *seq)
{
return asdl_seq_GET_UNTYPED(seq, 0);
}
/* Creates a new name of the form <first_name>.<second_name> */
expr_ty
_PyPegen_join_names_with_dot(Parser *p, expr_ty first_name, expr_ty second_name)
{
assert(first_name != NULL && second_name != NULL);
PyObject *uni = PyUnicode_FromFormat("%U.%U",
first_name->v.Name.id, second_name->v.Name.id);
if (!uni) {
return NULL;
}
PyInterpreterState *interp = _PyInterpreterState_GET();
_PyUnicode_InternImmortal(interp, &uni);
if (_PyArena_AddPyObject(p->arena, uni) < 0) {
Py_DECREF(uni);
return NULL;
}
return _PyAST_Name(uni, Load, EXTRA_EXPR(first_name, second_name));
}
/* Counts the total number of dots in seq's tokens */
int
_PyPegen_seq_count_dots(asdl_seq *seq)
{
int number_of_dots = 0;
for (Py_ssize_t i = 0, l = asdl_seq_LEN(seq); i < l; i++) {
Token *current_expr = asdl_seq_GET_UNTYPED(seq, i);
switch (current_expr->type) {
case ELLIPSIS:
number_of_dots += 3;
break;
case DOT:
number_of_dots += 1;
break;
default:
Py_UNREACHABLE();
}
}
return number_of_dots;
}
/* Creates an alias with '*' as the identifier name */
alias_ty
_PyPegen_alias_for_star(Parser *p, int lineno, int col_offset, int end_lineno,
int end_col_offset, PyArena *arena) {
PyObject *str = PyUnicode_InternFromString("*");
if (!str) {
return NULL;
}
if (_PyArena_AddPyObject(p->arena, str) < 0) {
Py_DECREF(str);
return NULL;
}
return _PyAST_alias(str, NULL, lineno, col_offset, end_lineno, end_col_offset, arena);
}
/* Creates a new asdl_seq* with the identifiers of all the names in seq */
asdl_identifier_seq *
_PyPegen_map_names_to_ids(Parser *p, asdl_expr_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
assert(len > 0);
asdl_identifier_seq *new_seq = _Py_asdl_identifier_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
expr_ty e = asdl_seq_GET(seq, i);
asdl_seq_SET(new_seq, i, e->v.Name.id);
}
return new_seq;
}
/* Constructs a CmpopExprPair */
CmpopExprPair *
_PyPegen_cmpop_expr_pair(Parser *p, cmpop_ty cmpop, expr_ty expr)
{
assert(expr != NULL);
CmpopExprPair *a = _PyArena_Malloc(p->arena, sizeof(CmpopExprPair));
if (!a) {
return NULL;
}
a->cmpop = cmpop;
a->expr = expr;
return a;
}
asdl_int_seq *
_PyPegen_get_cmpops(Parser *p, asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
assert(len > 0);
asdl_int_seq *new_seq = _Py_asdl_int_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
CmpopExprPair *pair = asdl_seq_GET_UNTYPED(seq, i);
asdl_seq_SET(new_seq, i, pair->cmpop);
}
return new_seq;
}
asdl_expr_seq *
_PyPegen_get_exprs(Parser *p, asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
assert(len > 0);
asdl_expr_seq *new_seq = _Py_asdl_expr_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
CmpopExprPair *pair = asdl_seq_GET_UNTYPED(seq, i);
asdl_seq_SET(new_seq, i, pair->expr);
}
return new_seq;
}
/* Creates an asdl_seq* where all the elements have been changed to have ctx as context */
static asdl_expr_seq *
_set_seq_context(Parser *p, asdl_expr_seq *seq, expr_context_ty ctx)
{
Py_ssize_t len = asdl_seq_LEN(seq);
if (len == 0) {
return NULL;
}
asdl_expr_seq *new_seq = _Py_asdl_expr_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
expr_ty e = asdl_seq_GET(seq, i);
asdl_seq_SET(new_seq, i, _PyPegen_set_expr_context(p, e, ctx));
}
return new_seq;
}
static expr_ty
_set_name_context(Parser *p, expr_ty e, expr_context_ty ctx)
{
return _PyAST_Name(e->v.Name.id, ctx, EXTRA_EXPR(e, e));
}
static expr_ty
_set_tuple_context(Parser *p, expr_ty e, expr_context_ty ctx)
{
return _PyAST_Tuple(
_set_seq_context(p, e->v.Tuple.elts, ctx),
ctx,
EXTRA_EXPR(e, e));
}
static expr_ty
_set_list_context(Parser *p, expr_ty e, expr_context_ty ctx)
{
return _PyAST_List(
_set_seq_context(p, e->v.List.elts, ctx),
ctx,
EXTRA_EXPR(e, e));
}
static expr_ty
_set_subscript_context(Parser *p, expr_ty e, expr_context_ty ctx)
{
return _PyAST_Subscript(e->v.Subscript.value, e->v.Subscript.slice,
ctx, EXTRA_EXPR(e, e));
}
static expr_ty
_set_attribute_context(Parser *p, expr_ty e, expr_context_ty ctx)
{
return _PyAST_Attribute(e->v.Attribute.value, e->v.Attribute.attr,
ctx, EXTRA_EXPR(e, e));
}
static expr_ty
_set_starred_context(Parser *p, expr_ty e, expr_context_ty ctx)
{
return _PyAST_Starred(_PyPegen_set_expr_context(p, e->v.Starred.value, ctx),
ctx, EXTRA_EXPR(e, e));
}
/* Creates an `expr_ty` equivalent to `expr` but with `ctx` as context */
expr_ty
_PyPegen_set_expr_context(Parser *p, expr_ty expr, expr_context_ty ctx)
{
assert(expr != NULL);
expr_ty new = NULL;
switch (expr->kind) {
case Name_kind:
new = _set_name_context(p, expr, ctx);
break;
case Tuple_kind:
new = _set_tuple_context(p, expr, ctx);
break;
case List_kind:
new = _set_list_context(p, expr, ctx);
break;
case Subscript_kind:
new = _set_subscript_context(p, expr, ctx);
break;
case Attribute_kind:
new = _set_attribute_context(p, expr, ctx);
break;
case Starred_kind:
new = _set_starred_context(p, expr, ctx);
break;
default:
new = expr;
}
return new;
}
/* Constructs a KeyValuePair that is used when parsing a dict's key value pairs */
KeyValuePair *
_PyPegen_key_value_pair(Parser *p, expr_ty key, expr_ty value)
{
KeyValuePair *a = _PyArena_Malloc(p->arena, sizeof(KeyValuePair));
if (!a) {
return NULL;
}
a->key = key;
a->value = value;
return a;
}
/* Extracts all keys from an asdl_seq* of KeyValuePair*'s */
asdl_expr_seq *
_PyPegen_get_keys(Parser *p, asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
asdl_expr_seq *new_seq = _Py_asdl_expr_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
KeyValuePair *pair = asdl_seq_GET_UNTYPED(seq, i);
asdl_seq_SET(new_seq, i, pair->key);
}
return new_seq;
}
/* Extracts all values from an asdl_seq* of KeyValuePair*'s */
asdl_expr_seq *
_PyPegen_get_values(Parser *p, asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
asdl_expr_seq *new_seq = _Py_asdl_expr_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
KeyValuePair *pair = asdl_seq_GET_UNTYPED(seq, i);
asdl_seq_SET(new_seq, i, pair->value);
}
return new_seq;
}
/* Constructs a KeyPatternPair that is used when parsing mapping & class patterns */
KeyPatternPair *
_PyPegen_key_pattern_pair(Parser *p, expr_ty key, pattern_ty pattern)
{
KeyPatternPair *a = _PyArena_Malloc(p->arena, sizeof(KeyPatternPair));
if (!a) {
return NULL;
}
a->key = key;
a->pattern = pattern;
return a;
}
/* Extracts all keys from an asdl_seq* of KeyPatternPair*'s */
asdl_expr_seq *
_PyPegen_get_pattern_keys(Parser *p, asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
asdl_expr_seq *new_seq = _Py_asdl_expr_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
KeyPatternPair *pair = asdl_seq_GET_UNTYPED(seq, i);
asdl_seq_SET(new_seq, i, pair->key);
}
return new_seq;
}
/* Extracts all patterns from an asdl_seq* of KeyPatternPair*'s */
asdl_pattern_seq *
_PyPegen_get_patterns(Parser *p, asdl_seq *seq)
{
Py_ssize_t len = asdl_seq_LEN(seq);
asdl_pattern_seq *new_seq = _Py_asdl_pattern_seq_new(len, p->arena);
if (!new_seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
KeyPatternPair *pair = asdl_seq_GET_UNTYPED(seq, i);
asdl_seq_SET(new_seq, i, pair->pattern);
}
return new_seq;
}
/* Constructs a NameDefaultPair */
NameDefaultPair *
_PyPegen_name_default_pair(Parser *p, arg_ty arg, expr_ty value, Token *tc)
{
NameDefaultPair *a = _PyArena_Malloc(p->arena, sizeof(NameDefaultPair));
if (!a) {
return NULL;
}
a->arg = _PyPegen_add_type_comment_to_arg(p, arg, tc);
a->value = value;
return a;
}
/* Constructs a SlashWithDefault */
SlashWithDefault *
_PyPegen_slash_with_default(Parser *p, asdl_arg_seq *plain_names, asdl_seq *names_with_defaults)
{
SlashWithDefault *a = _PyArena_Malloc(p->arena, sizeof(SlashWithDefault));
if (!a) {
return NULL;
}
a->plain_names = plain_names;
a->names_with_defaults = names_with_defaults;
return a;
}
/* Constructs a StarEtc */
StarEtc *
_PyPegen_star_etc(Parser *p, arg_ty vararg, asdl_seq *kwonlyargs, arg_ty kwarg)
{
StarEtc *a = _PyArena_Malloc(p->arena, sizeof(StarEtc));
if (!a) {
return NULL;
}
a->vararg = vararg;
a->kwonlyargs = kwonlyargs;
a->kwarg = kwarg;
return a;
}
asdl_seq *
_PyPegen_join_sequences(Parser *p, asdl_seq *a, asdl_seq *b)
{
Py_ssize_t first_len = asdl_seq_LEN(a);
Py_ssize_t second_len = asdl_seq_LEN(b);
asdl_seq *new_seq = (asdl_seq*)_Py_asdl_generic_seq_new(first_len + second_len, p->arena);
if (!new_seq) {
return NULL;
}
int k = 0;
for (Py_ssize_t i = 0; i < first_len; i++) {
asdl_seq_SET_UNTYPED(new_seq, k++, asdl_seq_GET_UNTYPED(a, i));
}
for (Py_ssize_t i = 0; i < second_len; i++) {
asdl_seq_SET_UNTYPED(new_seq, k++, asdl_seq_GET_UNTYPED(b, i));
}
return new_seq;
}
static asdl_arg_seq*
_get_names(Parser *p, asdl_seq *names_with_defaults)
{
Py_ssize_t len = asdl_seq_LEN(names_with_defaults);
asdl_arg_seq *seq = _Py_asdl_arg_seq_new(len, p->arena);
if (!seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
NameDefaultPair *pair = asdl_seq_GET_UNTYPED(names_with_defaults, i);
asdl_seq_SET(seq, i, pair->arg);
}
return seq;
}
static asdl_expr_seq *
_get_defaults(Parser *p, asdl_seq *names_with_defaults)
{
Py_ssize_t len = asdl_seq_LEN(names_with_defaults);
asdl_expr_seq *seq = _Py_asdl_expr_seq_new(len, p->arena);
if (!seq) {
return NULL;
}
for (Py_ssize_t i = 0; i < len; i++) {
NameDefaultPair *pair = asdl_seq_GET_UNTYPED(names_with_defaults, i);
asdl_seq_SET(seq, i, pair->value);
}
return seq;
}
static int
_make_posonlyargs(Parser *p,
asdl_arg_seq *slash_without_default,
SlashWithDefault *slash_with_default,
asdl_arg_seq **posonlyargs) {
if (slash_without_default != NULL) {
*posonlyargs = slash_without_default;
}
else if (slash_with_default != NULL) {
asdl_arg_seq *slash_with_default_names =
_get_names(p, slash_with_default->names_with_defaults);
if (!slash_with_default_names) {
return -1;
}
*posonlyargs = (asdl_arg_seq*)_PyPegen_join_sequences(
p,
(asdl_seq*)slash_with_default->plain_names,
(asdl_seq*)slash_with_default_names);
}
else {
*posonlyargs = _Py_asdl_arg_seq_new(0, p->arena);
}
return *posonlyargs == NULL ? -1 : 0;
}
static int
_make_posargs(Parser *p,
asdl_arg_seq *plain_names,
asdl_seq *names_with_default,
asdl_arg_seq **posargs) {
if (names_with_default != NULL) {
if (plain_names != NULL) {
asdl_arg_seq *names_with_default_names = _get_names(p, names_with_default);
if (!names_with_default_names) {
return -1;
}
*posargs = (asdl_arg_seq*)_PyPegen_join_sequences(
p,(asdl_seq*)plain_names, (asdl_seq*)names_with_default_names);
}
else {
*posargs = _get_names(p, names_with_default);
}
}
else {
if (plain_names != NULL) {
// With the current grammar, we never get here.
// If that has changed, remove the assert, and test thoroughly.
assert(0);
*posargs = plain_names;
}
else {
*posargs = _Py_asdl_arg_seq_new(0, p->arena);
}
}
return *posargs == NULL ? -1 : 0;
}
static int
_make_posdefaults(Parser *p,
SlashWithDefault *slash_with_default,
asdl_seq *names_with_default,
asdl_expr_seq **posdefaults) {
if (slash_with_default != NULL && names_with_default != NULL) {
asdl_expr_seq *slash_with_default_values =
_get_defaults(p, slash_with_default->names_with_defaults);
if (!slash_with_default_values) {
return -1;
}
asdl_expr_seq *names_with_default_values = _get_defaults(p, names_with_default);
if (!names_with_default_values) {
return -1;
}
*posdefaults = (asdl_expr_seq*)_PyPegen_join_sequences(
p,
(asdl_seq*)slash_with_default_values,
(asdl_seq*)names_with_default_values);
}
else if (slash_with_default == NULL && names_with_default != NULL) {
*posdefaults = _get_defaults(p, names_with_default);
}
else if (slash_with_default != NULL && names_with_default == NULL) {
*posdefaults = _get_defaults(p, slash_with_default->names_with_defaults);
}
else {
*posdefaults = _Py_asdl_expr_seq_new(0, p->arena);
}
return *posdefaults == NULL ? -1 : 0;
}
static int
_make_kwargs(Parser *p, StarEtc *star_etc,
asdl_arg_seq **kwonlyargs,
asdl_expr_seq **kwdefaults) {
if (star_etc != NULL && star_etc->kwonlyargs != NULL) {
*kwonlyargs = _get_names(p, star_etc->kwonlyargs);
}
else {
*kwonlyargs = _Py_asdl_arg_seq_new(0, p->arena);
}
if (*kwonlyargs == NULL) {
return -1;
}
if (star_etc != NULL && star_etc->kwonlyargs != NULL) {
*kwdefaults = _get_defaults(p, star_etc->kwonlyargs);
}
else {
*kwdefaults = _Py_asdl_expr_seq_new(0, p->arena);
}
if (*kwdefaults == NULL) {
return -1;
}
return 0;
}
/* Constructs an arguments_ty object out of all the parsed constructs in the parameters rule */
arguments_ty
_PyPegen_make_arguments(Parser *p, asdl_arg_seq *slash_without_default,
SlashWithDefault *slash_with_default, asdl_arg_seq *plain_names,
asdl_seq *names_with_default, StarEtc *star_etc)
{
asdl_arg_seq *posonlyargs;
if (_make_posonlyargs(p, slash_without_default, slash_with_default, &posonlyargs) == -1) {
return NULL;
}
asdl_arg_seq *posargs;
if (_make_posargs(p, plain_names, names_with_default, &posargs) == -1) {
return NULL;
}
asdl_expr_seq *posdefaults;
if (_make_posdefaults(p,slash_with_default, names_with_default, &posdefaults) == -1) {
return NULL;
}
arg_ty vararg = NULL;
if (star_etc != NULL && star_etc->vararg != NULL) {
vararg = star_etc->vararg;
}
asdl_arg_seq *kwonlyargs;
asdl_expr_seq *kwdefaults;
if (_make_kwargs(p, star_etc, &kwonlyargs, &kwdefaults) == -1) {
return NULL;
}
arg_ty kwarg = NULL;
if (star_etc != NULL && star_etc->kwarg != NULL) {
kwarg = star_etc->kwarg;
}
return _PyAST_arguments(posonlyargs, posargs, vararg, kwonlyargs,
kwdefaults, kwarg, posdefaults, p->arena);
}
/* Constructs an empty arguments_ty object, that gets used when a function accepts no
* arguments. */
arguments_ty
_PyPegen_empty_arguments(Parser *p)
{
asdl_arg_seq *posonlyargs = _Py_asdl_arg_seq_new(0, p->arena);
if (!posonlyargs) {
return NULL;
}
asdl_arg_seq *posargs = _Py_asdl_arg_seq_new(0, p->arena);
if (!posargs) {
return NULL;
}
asdl_expr_seq *posdefaults = _Py_asdl_expr_seq_new(0, p->arena);
if (!posdefaults) {
return NULL;
}
asdl_arg_seq *kwonlyargs = _Py_asdl_arg_seq_new(0, p->arena);
if (!kwonlyargs) {
return NULL;
}
asdl_expr_seq *kwdefaults = _Py_asdl_expr_seq_new(0, p->arena);
if (!kwdefaults) {
return NULL;
}
return _PyAST_arguments(posonlyargs, posargs, NULL, kwonlyargs,
kwdefaults, NULL, posdefaults, p->arena);
}
/* Encapsulates the value of an operator_ty into an AugOperator struct */
AugOperator *
_PyPegen_augoperator(Parser *p, operator_ty kind)
{
AugOperator *a = _PyArena_Malloc(p->arena, sizeof(AugOperator));
if (!a) {
return NULL;
}
a->kind = kind;
return a;
}
/* Construct a FunctionDef equivalent to function_def, but with decorators */
stmt_ty
_PyPegen_function_def_decorators(Parser *p, asdl_expr_seq *decorators, stmt_ty function_def)
{
assert(function_def != NULL);
if (function_def->kind == AsyncFunctionDef_kind) {
return _PyAST_AsyncFunctionDef(
function_def->v.AsyncFunctionDef.name,
function_def->v.AsyncFunctionDef.args,
function_def->v.AsyncFunctionDef.body, decorators,
function_def->v.AsyncFunctionDef.returns,
function_def->v.AsyncFunctionDef.type_comment,
function_def->v.AsyncFunctionDef.type_params,
function_def->lineno, function_def->col_offset,
function_def->end_lineno, function_def->end_col_offset, p->arena);
}
return _PyAST_FunctionDef(
function_def->v.FunctionDef.name,
function_def->v.FunctionDef.args,
function_def->v.FunctionDef.body, decorators,
function_def->v.FunctionDef.returns,
function_def->v.FunctionDef.type_comment,
function_def->v.FunctionDef.type_params,
function_def->lineno, function_def->col_offset,
function_def->end_lineno, function_def->end_col_offset, p->arena);
}
/* Construct a ClassDef equivalent to class_def, but with decorators */
stmt_ty
_PyPegen_class_def_decorators(Parser *p, asdl_expr_seq *decorators, stmt_ty class_def)
{
assert(class_def != NULL);
return _PyAST_ClassDef(
class_def->v.ClassDef.name,
class_def->v.ClassDef.bases, class_def->v.ClassDef.keywords,
class_def->v.ClassDef.body, decorators,
class_def->v.ClassDef.type_params,
class_def->lineno, class_def->col_offset, class_def->end_lineno,
class_def->end_col_offset, p->arena);
}
/* Construct a KeywordOrStarred */
KeywordOrStarred *
_PyPegen_keyword_or_starred(Parser *p, void *element, int is_keyword)
{
KeywordOrStarred *a = _PyArena_Malloc(p->arena, sizeof(KeywordOrStarred));
if (!a) {
return NULL;
}
a->element = element;
a->is_keyword = is_keyword;
return a;
}
/* Get the number of starred expressions in an asdl_seq* of KeywordOrStarred*s */
static int
_seq_number_of_starred_exprs(asdl_seq *seq)
{
int n = 0;
for (Py_ssize_t i = 0, l = asdl_seq_LEN(seq); i < l; i++) {
KeywordOrStarred *k = asdl_seq_GET_UNTYPED(seq, i);
if (!k->is_keyword) {
n++;
}
}
return n;
}
/* Extract the starred expressions of an asdl_seq* of KeywordOrStarred*s */
asdl_expr_seq *
_PyPegen_seq_extract_starred_exprs(Parser *p, asdl_seq *kwargs)
{
int new_len = _seq_number_of_starred_exprs(kwargs);
if (new_len == 0) {
return NULL;
}
asdl_expr_seq *new_seq = _Py_asdl_expr_seq_new(new_len, p->arena);
if (!new_seq) {
return NULL;
}
int idx = 0;
for (Py_ssize_t i = 0, len = asdl_seq_LEN(kwargs); i < len; i++) {
KeywordOrStarred *k = asdl_seq_GET_UNTYPED(kwargs, i);
if (!k->is_keyword) {
asdl_seq_SET(new_seq, idx++, k->element);
}
}
return new_seq;
}
/* Return a new asdl_seq* with only the keywords in kwargs */
asdl_keyword_seq*
_PyPegen_seq_delete_starred_exprs(Parser *p, asdl_seq *kwargs)
{
Py_ssize_t len = asdl_seq_LEN(kwargs);
Py_ssize_t new_len = len - _seq_number_of_starred_exprs(kwargs);
if (new_len == 0) {
return NULL;
}
asdl_keyword_seq *new_seq = _Py_asdl_keyword_seq_new(new_len, p->arena);
if (!new_seq) {
return NULL;
}
int idx = 0;
for (Py_ssize_t i = 0; i < len; i++) {
KeywordOrStarred *k = asdl_seq_GET_UNTYPED(kwargs, i);
if (k->is_keyword) {
asdl_seq_SET(new_seq, idx++, k->element);
}
}
return new_seq;
}
expr_ty
_PyPegen_ensure_imaginary(Parser *p, expr_ty exp)
{
if (exp->kind != Constant_kind || !PyComplex_CheckExact(exp->v.Constant.value)) {
RAISE_SYNTAX_ERROR_KNOWN_LOCATION(exp, "imaginary number required in complex literal");
return NULL;
}
return exp;
}
expr_ty
_PyPegen_ensure_real(Parser *p, expr_ty exp)
{
if (exp->kind != Constant_kind || PyComplex_CheckExact(exp->v.Constant.value)) {
RAISE_SYNTAX_ERROR_KNOWN_LOCATION(exp, "real number required in complex literal");
return NULL;
}
return exp;
}
mod_ty
_PyPegen_make_module(Parser *p, asdl_stmt_seq *a) {
asdl_type_ignore_seq *type_ignores = NULL;
Py_ssize_t num = p->type_ignore_comments.num_items;
if (num > 0) {
// Turn the raw (comment, lineno) pairs into TypeIgnore objects in the arena
type_ignores = _Py_asdl_type_ignore_seq_new(num, p->arena);
if (type_ignores == NULL) {
return NULL;
}
for (Py_ssize_t i = 0; i < num; i++) {
PyObject *tag = _PyPegen_new_type_comment(p, p->type_ignore_comments.items[i].comment);
if (tag == NULL) {
return NULL;
}
type_ignore_ty ti = _PyAST_TypeIgnore(p->type_ignore_comments.items[i].lineno,
tag, p->arena);
if (ti == NULL) {
return NULL;
}
asdl_seq_SET(type_ignores, i, ti);
}
}
return _PyAST_Module(a, type_ignores, p->arena);
}
PyObject *
_PyPegen_new_type_comment(Parser *p, const char *s)
{
PyObject *res = PyUnicode_DecodeUTF8(s, strlen(s), NULL);
if (res == NULL) {
return NULL;
}
if (_PyArena_AddPyObject(p->arena, res) < 0) {
Py_DECREF(res);
return NULL;
}
return res;
}
arg_ty
_PyPegen_add_type_comment_to_arg(Parser *p, arg_ty a, Token *tc)
{
if (tc == NULL) {
return a;
}
const char *bytes = PyBytes_AsString(tc->bytes);
if (bytes == NULL) {
return NULL;
}
PyObject *tco = _PyPegen_new_type_comment(p, bytes);
if (tco == NULL) {
return NULL;
}
return _PyAST_arg(a->arg, a->annotation, tco,
a->lineno, a->col_offset, a->end_lineno, a->end_col_offset,
p->arena);
}
/* Checks if the NOTEQUAL token is valid given the current parser flags
0 indicates success and nonzero indicates failure (an exception may be set) */
int
_PyPegen_check_barry_as_flufl(Parser *p, Token* t) {
assert(t->bytes != NULL);
assert(t->type == NOTEQUAL);
const char* tok_str = PyBytes_AS_STRING(t->bytes);
if (p->flags & PyPARSE_BARRY_AS_BDFL && strcmp(tok_str, "<>") != 0) {
RAISE_SYNTAX_ERROR("with Barry as BDFL, use '<>' instead of '!='");
return -1;
}
if (!(p->flags & PyPARSE_BARRY_AS_BDFL)) {
return strcmp(tok_str, "!=");
}
return 0;
}
int
_PyPegen_check_legacy_stmt(Parser *p, expr_ty name) {
if (name->kind != Name_kind) {
return 0;
}
const char* candidates[2] = {"print", "exec"};
for (int i=0; i<2; i++) {
if (PyUnicode_CompareWithASCIIString(name->v.Name.id, candidates[i]) == 0) {
return 1;
}
}
return 0;
}
static ResultTokenWithMetadata *
result_token_with_metadata(Parser *p, void *result, PyObject *metadata)
{
ResultTokenWithMetadata *res = _PyArena_Malloc(p->arena, sizeof(ResultTokenWithMetadata));
if (res == NULL) {
return NULL;
}
res->metadata = metadata;
res->result = result;
return res;
}
ResultTokenWithMetadata *
_PyPegen_check_fstring_conversion(Parser *p, Token* conv_token, expr_ty conv)
{
if (conv_token->lineno != conv->lineno || conv_token->end_col_offset != conv->col_offset) {
return RAISE_SYNTAX_ERROR_KNOWN_RANGE(
conv_token, conv,
"f-string: conversion type must come right after the exclamanation mark"
);
}
return result_token_with_metadata(p, conv, conv_token->metadata);
}
static asdl_expr_seq *
unpack_top_level_joined_strs(Parser *p, asdl_expr_seq *raw_expressions);
ResultTokenWithMetadata *
_PyPegen_setup_full_format_spec(Parser *p, Token *colon, asdl_expr_seq *spec, int lineno, int col_offset,
int end_lineno, int end_col_offset, PyArena *arena)
{
if (!spec) {
return NULL;
}
// This is needed to keep compatibility with 3.11, where an empty format
// spec is parsed as an *empty* JoinedStr node, instead of having an empty
// constant in it.
Py_ssize_t n_items = asdl_seq_LEN(spec);
Py_ssize_t non_empty_count = 0;
for (Py_ssize_t i = 0; i < n_items; i++) {
expr_ty item = asdl_seq_GET(spec, i);
non_empty_count += !(item->kind == Constant_kind &&
PyUnicode_CheckExact(item->v.Constant.value) &&
PyUnicode_GET_LENGTH(item->v.Constant.value) == 0);
}
if (non_empty_count != n_items) {
asdl_expr_seq *resized_spec =
_Py_asdl_expr_seq_new(non_empty_count, p->arena);
if (resized_spec == NULL) {
return NULL;
}
Py_ssize_t j = 0;
for (Py_ssize_t i = 0; i < n_items; i++) {
expr_ty item = asdl_seq_GET(spec, i);
if (item->kind == Constant_kind &&
PyUnicode_CheckExact(item->v.Constant.value) &&
PyUnicode_GET_LENGTH(item->v.Constant.value) == 0) {
continue;
}
asdl_seq_SET(resized_spec, j++, item);
}
assert(j == non_empty_count);
spec = resized_spec;
}
expr_ty res;
Py_ssize_t n = asdl_seq_LEN(spec);
if (n == 0 || (n == 1 && asdl_seq_GET(spec, 0)->kind == Constant_kind)) {
res = _PyAST_JoinedStr(spec, lineno, col_offset, end_lineno,
end_col_offset, p->arena);
} else {
res = _PyPegen_concatenate_strings(p, spec,
lineno, col_offset, end_lineno,
end_col_offset, arena);
}
if (!res) {
return NULL;
}
return result_token_with_metadata(p, res, colon->metadata);
}
const char *
_PyPegen_get_expr_name(expr_ty e)
{
assert(e != NULL);
switch (e->kind) {
case Attribute_kind:
return "attribute";
case Subscript_kind:
return "subscript";
case Starred_kind:
return "starred";
case Name_kind:
return "name";
case List_kind:
return "list";
case Tuple_kind:
return "tuple";
case Lambda_kind:
return "lambda";
case Call_kind:
return "function call";
case BoolOp_kind:
case BinOp_kind:
case UnaryOp_kind:
return "expression";
case GeneratorExp_kind:
return "generator expression";
case Yield_kind:
case YieldFrom_kind:
return "yield expression";
case Await_kind:
return "await expression";
case ListComp_kind:
return "list comprehension";
case SetComp_kind:
return "set comprehension";
case DictComp_kind:
return "dict comprehension";
case Dict_kind:
return "dict literal";
case Set_kind:
return "set display";
case JoinedStr_kind:
case FormattedValue_kind:
return "f-string expression";
case Constant_kind: {
PyObject *value = e->v.Constant.value;
if (value == Py_None) {
return "None";
}
if (value == Py_False) {
return "False";
}
if (value == Py_True) {
return "True";
}
if (value == Py_Ellipsis) {
return "ellipsis";
}
return "literal";
}
case Compare_kind:
return "comparison";
case IfExp_kind:
return "conditional expression";
case NamedExpr_kind:
return "named expression";
default:
PyErr_Format(PyExc_SystemError,
"unexpected expression in assignment %d (line %d)",
e->kind, e->lineno);
return NULL;
}
}
expr_ty
_PyPegen_get_last_comprehension_item(comprehension_ty comprehension) {
if (comprehension->ifs == NULL || asdl_seq_LEN(comprehension->ifs) == 0) {
return comprehension->iter;
}
return PyPegen_last_item(comprehension->ifs, expr_ty);
}
expr_ty _PyPegen_collect_call_seqs(Parser *p, asdl_expr_seq *a, asdl_seq *b,
int lineno, int col_offset, int end_lineno,
int end_col_offset, PyArena *arena) {
Py_ssize_t args_len = asdl_seq_LEN(a);
Py_ssize_t total_len = args_len;
if (b == NULL) {
return _PyAST_Call(_PyPegen_dummy_name(p), a, NULL, lineno, col_offset,
end_lineno, end_col_offset, arena);
}
asdl_expr_seq *starreds = _PyPegen_seq_extract_starred_exprs(p, b);
asdl_keyword_seq *keywords = _PyPegen_seq_delete_starred_exprs(p, b);
if (starreds) {
total_len += asdl_seq_LEN(starreds);
}
asdl_expr_seq *args = _Py_asdl_expr_seq_new(total_len, arena);
Py_ssize_t i = 0;
for (i = 0; i < args_len; i++) {
asdl_seq_SET(args, i, asdl_seq_GET(a, i));
}
for (; i < total_len; i++) {
asdl_seq_SET(args, i, asdl_seq_GET(starreds, i - args_len));
}
return _PyAST_Call(_PyPegen_dummy_name(p), args, keywords, lineno,
col_offset, end_lineno, end_col_offset, arena);
}
// AST Error reporting helpers
expr_ty
_PyPegen_get_invalid_target(expr_ty e, TARGETS_TYPE targets_type)
{
if (e == NULL) {
return NULL;
}
#define VISIT_CONTAINER(CONTAINER, TYPE) do { \
Py_ssize_t len = asdl_seq_LEN((CONTAINER)->v.TYPE.elts);\
for (Py_ssize_t i = 0; i < len; i++) {\
expr_ty other = asdl_seq_GET((CONTAINER)->v.TYPE.elts, i);\
expr_ty child = _PyPegen_get_invalid_target(other, targets_type);\
if (child != NULL) {\
return child;\
}\
}\
} while (0)
// We only need to visit List and Tuple nodes recursively as those
// are the only ones that can contain valid names in targets when
// they are parsed as expressions. Any other kind of expression
// that is a container (like Sets or Dicts) is directly invalid and
// we don't need to visit it recursively.
switch (e->kind) {
case List_kind:
VISIT_CONTAINER(e, List);
return NULL;
case Tuple_kind:
VISIT_CONTAINER(e, Tuple);
return NULL;
case Starred_kind:
if (targets_type == DEL_TARGETS) {
return e;
}
return _PyPegen_get_invalid_target(e->v.Starred.value, targets_type);
case Compare_kind:
// This is needed, because the `a in b` in `for a in b` gets parsed
// as a comparison, and so we need to search the left side of the comparison
// for invalid targets.
if (targets_type == FOR_TARGETS) {
cmpop_ty cmpop = (cmpop_ty) asdl_seq_GET(e->v.Compare.ops, 0);
if (cmpop == In) {
return _PyPegen_get_invalid_target(e->v.Compare.left, targets_type);
}
return NULL;
}
return e;
case Name_kind:
case Subscript_kind:
case Attribute_kind:
return NULL;
default:
return e;
}
}
void *_PyPegen_arguments_parsing_error(Parser *p, expr_ty e) {
int kwarg_unpacking = 0;
for (Py_ssize_t i = 0, l = asdl_seq_LEN(e->v.Call.keywords); i < l; i++) {
keyword_ty keyword = asdl_seq_GET(e->v.Call.keywords, i);
if (!keyword->arg) {
kwarg_unpacking = 1;
}
}
const char *msg = NULL;
if (kwarg_unpacking) {
msg = "positional argument follows keyword argument unpacking";
} else {
msg = "positional argument follows keyword argument";
}
return RAISE_SYNTAX_ERROR(msg);
}
void *
_PyPegen_nonparen_genexp_in_call(Parser *p, expr_ty args, asdl_comprehension_seq *comprehensions)
{
/* The rule that calls this function is 'args for_if_clauses'.
For the input f(L, x for x in y), L and x are in args and
the for is parsed as a for_if_clause. We have to check if
len <= 1, so that input like dict((a, b) for a, b in x)
gets successfully parsed and then we pass the last
argument (x in the above example) as the location of the
error */
Py_ssize_t len = asdl_seq_LEN(args->v.Call.args);
if (len <= 1) {
return NULL;
}
comprehension_ty last_comprehension = PyPegen_last_item(comprehensions, comprehension_ty);
return RAISE_SYNTAX_ERROR_KNOWN_RANGE(
(expr_ty) asdl_seq_GET(args->v.Call.args, len - 1),
_PyPegen_get_last_comprehension_item(last_comprehension),
"Generator expression must be parenthesized"
);
}
// Fstring stuff
static expr_ty
_PyPegen_decode_fstring_part(Parser* p, int is_raw, expr_ty constant, Token* token) {
assert(PyUnicode_CheckExact(constant->v.Constant.value));
const char* bstr = PyUnicode_AsUTF8(constant->v.Constant.value);
if (bstr == NULL) {
return NULL;
}
size_t len;
if (strcmp(bstr, "{{") == 0 || strcmp(bstr, "}}") == 0) {
len = 1;
} else {
len = strlen(bstr);
}
is_raw = is_raw || strchr(bstr, '\\') == NULL;
PyObject *str = _PyPegen_decode_string(p, is_raw, bstr, len, token);
if (str == NULL) {
_Pypegen_raise_decode_error(p);
return NULL;
}
if (_PyArena_AddPyObject(p->arena, str) < 0) {
Py_DECREF(str);
return NULL;
}
return _PyAST_Constant(str, NULL, constant->lineno, constant->col_offset,
constant->end_lineno, constant->end_col_offset,
p->arena);
}
static asdl_expr_seq *
unpack_top_level_joined_strs(Parser *p, asdl_expr_seq *raw_expressions)
{
/* The parser might put multiple f-string values into an individual
* JoinedStr node at the top level due to stuff like f-string debugging
* expressions. This function flattens those and promotes them to the
* upper level. Only simplifies AST, but the compiler already takes care
* of the regular output, so this is not necessary if you are not going
* to expose the output AST to Python level. */
Py_ssize_t i, req_size, raw_size;
req_size = raw_size = asdl_seq_LEN(raw_expressions);
expr_ty expr;
for (i = 0; i < raw_size; i++) {
expr = asdl_seq_GET(raw_expressions, i);
if (expr->kind == JoinedStr_kind) {
req_size += asdl_seq_LEN(expr->v.JoinedStr.values) - 1;
}
}
asdl_expr_seq *expressions = _Py_asdl_expr_seq_new(req_size, p->arena);
Py_ssize_t raw_index, req_index = 0;
for (raw_index = 0; raw_index < raw_size; raw_index++) {
expr = asdl_seq_GET(raw_expressions, raw_index);
if (expr->kind == JoinedStr_kind) {
asdl_expr_seq *values = expr->v.JoinedStr.values;
for (Py_ssize_t n = 0; n < asdl_seq_LEN(values); n++) {
asdl_seq_SET(expressions, req_index, asdl_seq_GET(values, n));
req_index++;
}
} else {
asdl_seq_SET(expressions, req_index, expr);
req_index++;
}
}
return expressions;
}
expr_ty
_PyPegen_joined_str(Parser *p, Token* a, asdl_expr_seq* raw_expressions, Token*b) {
asdl_expr_seq *expr = unpack_top_level_joined_strs(p, raw_expressions);
Py_ssize_t n_items = asdl_seq_LEN(expr);
const char* quote_str = PyBytes_AsString(a->bytes);
if (quote_str == NULL) {
return NULL;
}
int is_raw = strpbrk(quote_str, "rR") != NULL;
asdl_expr_seq *seq = _Py_asdl_expr_seq_new(n_items, p->arena);
if (seq == NULL) {
return NULL;
}
Py_ssize_t index = 0;
for (Py_ssize_t i = 0; i < n_items; i++) {
expr_ty item = asdl_seq_GET(expr, i);
if (item->kind == Constant_kind) {
item = _PyPegen_decode_fstring_part(p, is_raw, item, b);
if (item == NULL) {
return NULL;
}
/* Tokenizer emits string parts even when the underlying string
might become an empty value (e.g. FSTRING_MIDDLE with the value \\n)
so we need to check for them and simplify it here. */
if (PyUnicode_CheckExact(item->v.Constant.value)
&& PyUnicode_GET_LENGTH(item->v.Constant.value) == 0) {
continue;
}
}
asdl_seq_SET(seq, index++, item);
}
asdl_expr_seq *resized_exprs;
if (index != n_items) {
resized_exprs = _Py_asdl_expr_seq_new(index, p->arena);
if (resized_exprs == NULL) {
return NULL;
}
for (Py_ssize_t i = 0; i < index; i++) {
asdl_seq_SET(resized_exprs, i, asdl_seq_GET(seq, i));
}
}
else {
resized_exprs = seq;
}
return _PyAST_JoinedStr(resized_exprs, a->lineno, a->col_offset,
b->end_lineno, b->end_col_offset,
p->arena);
}
expr_ty _PyPegen_decoded_constant_from_token(Parser* p, Token* tok) {
Py_ssize_t bsize;
char* bstr;
if (PyBytes_AsStringAndSize(tok->bytes, &bstr, &bsize) == -1) {
return NULL;
}
PyObject* str = _PyPegen_decode_string(p, 0, bstr, bsize, tok);
if (str == NULL) {
return NULL;
}
if (_PyArena_AddPyObject(p->arena, str) < 0) {
Py_DECREF(str);
return NULL;
}
return _PyAST_Constant(str, NULL, tok->lineno, tok->col_offset,
tok->end_lineno, tok->end_col_offset,
p->arena);
}
expr_ty _PyPegen_constant_from_token(Parser* p, Token* tok) {
char* bstr = PyBytes_AsString(tok->bytes);
if (bstr == NULL) {
return NULL;
}
PyObject* str = PyUnicode_FromString(bstr);
if (str == NULL) {
return NULL;
}
if (_PyArena_AddPyObject(p->arena, str) < 0) {
Py_DECREF(str);
return NULL;
}
return _PyAST_Constant(str, NULL, tok->lineno, tok->col_offset,
tok->end_lineno, tok->end_col_offset,
p->arena);
}
expr_ty _PyPegen_constant_from_string(Parser* p, Token* tok) {
char* the_str = PyBytes_AsString(tok->bytes);
if (the_str == NULL) {
return NULL;
}
PyObject *s = _PyPegen_parse_string(p, tok);
if (s == NULL) {
_Pypegen_raise_decode_error(p);
return NULL;
}
if (_PyArena_AddPyObject(p->arena, s) < 0) {
Py_DECREF(s);
return NULL;
}
PyObject *kind = NULL;
if (the_str && the_str[0] == 'u') {
kind = _PyPegen_new_identifier(p, "u");
if (kind == NULL) {
return NULL;
}
}
return _PyAST_Constant(s, kind, tok->lineno, tok->col_offset, tok->end_lineno, tok->end_col_offset, p->arena);
}
expr_ty _PyPegen_formatted_value(Parser *p, expr_ty expression, Token *debug, ResultTokenWithMetadata *conversion,
ResultTokenWithMetadata *format, Token *closing_brace, int lineno, int col_offset,
int end_lineno, int end_col_offset, PyArena *arena) {
int conversion_val = -1;
if (conversion != NULL) {
expr_ty conversion_expr = (expr_ty) conversion->result;
assert(conversion_expr->kind == Name_kind);
Py_UCS4 first = PyUnicode_READ_CHAR(conversion_expr->v.Name.id, 0);
if (PyUnicode_GET_LENGTH(conversion_expr->v.Name.id) > 1 ||
!(first == 's' || first == 'r' || first == 'a')) {
RAISE_SYNTAX_ERROR_KNOWN_LOCATION(conversion_expr,
"f-string: invalid conversion character %R: expected 's', 'r', or 'a'",
conversion_expr->v.Name.id);
return NULL;
}
conversion_val = Py_SAFE_DOWNCAST(first, Py_UCS4, int);
}
else if (debug && !format) {
/* If no conversion is specified, use !r for debug expressions */
conversion_val = (int)'r';
}
expr_ty formatted_value = _PyAST_FormattedValue(
expression, conversion_val, format ? (expr_ty) format->result : NULL,
lineno, col_offset, end_lineno,
end_col_offset, arena
);
if (debug) {
/* Find the non whitespace token after the "=" */
int debug_end_line, debug_end_offset;
PyObject *debug_metadata;
if (conversion) {
debug_end_line = ((expr_ty) conversion->result)->lineno;
debug_end_offset = ((expr_ty) conversion->result)->col_offset;
debug_metadata = conversion->metadata;
}
else if (format) {
debug_end_line = ((expr_ty) format->result)->lineno;
debug_end_offset = ((expr_ty) format->result)->col_offset + 1;
debug_metadata = format->metadata;
}
else {
debug_end_line = end_lineno;
debug_end_offset = end_col_offset;
debug_metadata = closing_brace->metadata;
}
expr_ty debug_text = _PyAST_Constant(debug_metadata, NULL, lineno, col_offset + 1, debug_end_line,
debug_end_offset - 1, p->arena);
if (!debug_text) {
return NULL;
}
asdl_expr_seq *values = _Py_asdl_expr_seq_new(2, arena);
asdl_seq_SET(values, 0, debug_text);
asdl_seq_SET(values, 1, formatted_value);
return _PyAST_JoinedStr(values, lineno, col_offset, debug_end_line, debug_end_offset, p->arena);
}
else {
return formatted_value;
}
}
expr_ty
_PyPegen_concatenate_strings(Parser *p, asdl_expr_seq *strings,
int lineno, int col_offset, int end_lineno,
int end_col_offset, PyArena *arena)
{
Py_ssize_t len = asdl_seq_LEN(strings);
assert(len > 0);
int f_string_found = 0;
int unicode_string_found = 0;
int bytes_found = 0;
Py_ssize_t i = 0;
Py_ssize_t n_flattened_elements = 0;
for (i = 0; i < len; i++) {
expr_ty elem = asdl_seq_GET(strings, i);
switch(elem->kind) {
case Constant_kind:
if (PyBytes_CheckExact(elem->v.Constant.value)) {
bytes_found = 1;
} else {
unicode_string_found = 1;
}
n_flattened_elements++;
break;
case JoinedStr_kind:
n_flattened_elements += asdl_seq_LEN(elem->v.JoinedStr.values);
f_string_found = 1;
break;
default:
n_flattened_elements++;
f_string_found = 1;
break;
}
}
if ((unicode_string_found || f_string_found) && bytes_found) {
RAISE_SYNTAX_ERROR("cannot mix bytes and nonbytes literals");
return NULL;
}
if (bytes_found) {
PyObject* res = PyBytes_FromString("");
/* Bytes literals never get a kind, but just for consistency
since they are represented as Constant nodes, we'll mirror
the same behavior as unicode strings for determining the
kind. */
PyObject* kind = asdl_seq_GET(strings, 0)->v.Constant.kind;
for (i = 0; i < len; i++) {
expr_ty elem = asdl_seq_GET(strings, i);
PyBytes_Concat(&res, elem->v.Constant.value);
}
if (!res || _PyArena_AddPyObject(arena, res) < 0) {
Py_XDECREF(res);
return NULL;
}
return _PyAST_Constant(res, kind, lineno, col_offset, end_lineno, end_col_offset, p->arena);
}
if (!f_string_found && len == 1) {
return asdl_seq_GET(strings, 0);
}
asdl_expr_seq* flattened = _Py_asdl_expr_seq_new(n_flattened_elements, p->arena);
if (flattened == NULL) {
return NULL;
}
/* build flattened list */
Py_ssize_t current_pos = 0;
Py_ssize_t j = 0;
for (i = 0; i < len; i++) {
expr_ty elem = asdl_seq_GET(strings, i);
switch(elem->kind) {
case JoinedStr_kind:
for (j = 0; j < asdl_seq_LEN(elem->v.JoinedStr.values); j++) {
expr_ty subvalue = asdl_seq_GET(elem->v.JoinedStr.values, j);
if (subvalue == NULL) {
return NULL;
}
asdl_seq_SET(flattened, current_pos++, subvalue);
}
break;
default:
asdl_seq_SET(flattened, current_pos++, elem);
break;
}
}
/* calculate folded element count */
Py_ssize_t n_elements = 0;
int prev_is_constant = 0;
for (i = 0; i < n_flattened_elements; i++) {
expr_ty elem = asdl_seq_GET(flattened, i);
/* The concatenation of a FormattedValue and an empty Constant should
lead to the FormattedValue itself. Thus, we will not take any empty
constants into account, just as in `_PyPegen_joined_str` */
if (f_string_found && elem->kind == Constant_kind &&
PyUnicode_CheckExact(elem->v.Constant.value) &&
PyUnicode_GET_LENGTH(elem->v.Constant.value) == 0)
continue;
if (!prev_is_constant || elem->kind != Constant_kind) {
n_elements++;
}
prev_is_constant = elem->kind == Constant_kind;
}
asdl_expr_seq* values = _Py_asdl_expr_seq_new(n_elements, p->arena);
if (values == NULL) {
return NULL;
}
/* build folded list */
_PyUnicodeWriter writer;
current_pos = 0;
for (i = 0; i < n_flattened_elements; i++) {
expr_ty elem = asdl_seq_GET(flattened, i);
/* if the current elem and the following are constants,
fold them and all consequent constants */
if (elem->kind == Constant_kind) {
if (i + 1 < n_flattened_elements &&
asdl_seq_GET(flattened, i + 1)->kind == Constant_kind) {
expr_ty first_elem = elem;
/* When a string is getting concatenated, the kind of the string
is determined by the first string in the concatenation
sequence.
u"abc" "def" -> u"abcdef"
"abc" u"abc" -> "abcabc" */
PyObject *kind = elem->v.Constant.kind;
_PyUnicodeWriter_Init(&writer);
expr_ty last_elem = elem;
for (j = i; j < n_flattened_elements; j++) {
expr_ty current_elem = asdl_seq_GET(flattened, j);
if (current_elem->kind == Constant_kind) {
if (_PyUnicodeWriter_WriteStr(
&writer, current_elem->v.Constant.value)) {
_PyUnicodeWriter_Dealloc(&writer);
return NULL;
}
last_elem = current_elem;
} else {
break;
}
}
i = j - 1;
PyObject *concat_str = _PyUnicodeWriter_Finish(&writer);
if (concat_str == NULL) {
_PyUnicodeWriter_Dealloc(&writer);
return NULL;
}
if (_PyArena_AddPyObject(p->arena, concat_str) < 0) {
Py_DECREF(concat_str);
return NULL;
}
elem = _PyAST_Constant(concat_str, kind, first_elem->lineno,
first_elem->col_offset,
last_elem->end_lineno,
last_elem->end_col_offset, p->arena);
if (elem == NULL) {
return NULL;
}
}
/* Drop all empty contanst strings */
if (f_string_found &&
PyUnicode_CheckExact(elem->v.Constant.value) &&
PyUnicode_GET_LENGTH(elem->v.Constant.value) == 0) {
continue;
}
}
asdl_seq_SET(values, current_pos++, elem);
}
if (!f_string_found) {
assert(n_elements == 1);
expr_ty elem = asdl_seq_GET(values, 0);
assert(elem->kind == Constant_kind);
return elem;
}
assert(current_pos == n_elements);
return _PyAST_JoinedStr(values, lineno, col_offset, end_lineno, end_col_offset, p->arena);
}