Function can_use_list_sequence_fastpath

python/pyfory/cpp/pyfory.cc:575–628

}

static bool can_use_list_sequence_fastpath(PyObject **items, Py_ssize_t size,
                                           uint8_t type_id) {
  // This gate is not only about type checks:
  // it enforces "no Python callback during conversion" for the raw ob_item
  // path. If conversion can invoke user code (e.g. __int__/__float__/subclass
  // hooks), a list may be mutated while iterating raw pointers, which is
  // unsafe.
  switch (static_cast<TypeId>(type_id)) {
  case TypeId::STRING:
    for (Py_ssize_t i = 0; i < size; ++i) {
      if (!PyUnicode_CheckExact(items[i])) {
        return false;
      }
    }
    return true;
  case TypeId::VARINT64:
  case TypeId::INT64:
  case TypeId::TAGGED_INT64:
  case TypeId::VARINT32:
  case TypeId::INT32:
  case TypeId::VAR_UINT64:
  case TypeId::UINT64:
  case TypeId::TAGGED_UINT64:
  case TypeId::VAR_UINT32:
  case TypeId::UINT32:
  case TypeId::UINT8:
  case TypeId::INT8:
  case TypeId::UINT16:
  case TypeId::INT16:
    for (Py_ssize_t i = 0; i < size; ++i) {
      if (!PyLong_CheckExact(items[i])) {
        return false;
      }
    }
    return true;
  case TypeId::BOOL:
    for (Py_ssize_t i = 0; i < size; ++i) {
      if (items[i] != Py_True && items[i] != Py_False) {
        return false;
      }
    }
    return true;
  case TypeId::FLOAT32:
  case TypeId::FLOAT64:
    for (Py_ssize_t i = 0; i < size; ++i) {
      if (!PyFloat_CheckExact(items[i])) {
        return false;
      }
    }
    return true;
  default:
    return false;
  }
}

template <typename T>
static bool py_long_to_integral_range(PyObject *value, const char *type_name,