// Copyright 2013 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/key-accumulator.h"
#include "src/elements.h"
#include "src/factory.h"
#include "src/isolate-inl.h"
#include "src/objects-inl.h"
#include "src/property-descriptor.h"
namespace v8 {
namespace internal {
KeyAccumulator::~KeyAccumulator() {
for (size_t i = 0; i < elements_.size(); i++) {
delete elements_[i];
}
}
Handle<FixedArray> KeyAccumulator::GetKeys(GetKeysConversion convert) {
if (length_ == 0) {
return isolate_->factory()->empty_fixed_array();
}
// Make sure we have all the lengths collected.
NextPrototype();
// Assemble the result array by first adding the element keys and then the
// property keys. We use the total number of String + Symbol keys per level in
// |level_lengths_| and the available element keys in the corresponding bucket
// in |elements_| to deduce the number of keys to take from the
// |string_properties_| and |symbol_properties_| set.
Handle<FixedArray> result = isolate_->factory()->NewFixedArray(length_);
int insertion_index = 0;
int string_properties_index = 0;
int symbol_properties_index = 0;
// String and Symbol lengths always come in pairs:
size_t max_level = level_lengths_.size() / 2;
for (size_t level = 0; level < max_level; level++) {
int num_string_properties = level_lengths_[level * 2];
int num_symbol_properties = level_lengths_[level * 2 + 1];
if (num_string_properties < 0) {
// If the |num_string_properties| is negative, the current level contains
// properties from a proxy, hence we skip the integer keys in |elements_|
// since proxies define the complete ordering.
num_string_properties = -num_string_properties;
} else if (level < elements_.size()) {
// Add the element indices for this prototype level.
std::vector<uint32_t>* elements = elements_[level];
int num_elements = static_cast<int>(elements->size());
for (int i = 0; i < num_elements; i++) {
Handle<Object> key;
if (convert == KEEP_NUMBERS) {
key = isolate_->factory()->NewNumberFromUint(elements->at(i));
} else {
key = isolate_->factory()->Uint32ToString(elements->at(i));
}
result->set(insertion_index, *key);
insertion_index++;
}
}
// Add the string property keys for this prototype level.
for (int i = 0; i < num_string_properties; i++) {
Object* key = string_properties_->KeyAt(string_properties_index);
result->set(insertion_index, key);
insertion_index++;
string_properties_index++;
}
// Add the symbol property keys for this prototype level.
for (int i = 0; i < num_symbol_properties; i++) {
Object* key = symbol_properties_->KeyAt(symbol_properties_index);
result->set(insertion_index, key);
insertion_index++;
symbol_properties_index++;
}
}
DCHECK_EQ(insertion_index, length_);
return result;
}
namespace {
bool AccumulatorHasKey(std::vector<uint32_t>* sub_elements, uint32_t key) {
return std::binary_search(sub_elements->begin(), sub_elements->end(), key);
}
} // namespace
bool KeyAccumulator::AddKey(Object* key, AddKeyConversion convert) {
return AddKey(handle(key, isolate_), convert);
}
bool KeyAccumulator::AddKey(Handle<Object> key, AddKeyConversion convert) {
if (key->IsSymbol()) {
if (filter_ & SKIP_SYMBOLS) return false;
if (Handle<Symbol>::cast(key)->is_private()) return false;
return AddSymbolKey(key);
}
if (filter_ & SKIP_STRINGS) return false;
// Make sure we do not add keys to a proxy-level (see AddKeysFromProxy).
DCHECK_LE(0, level_string_length_);
// In some cases (e.g. proxies) we might get in String-converted ints which
// should be added to the elements list instead of the properties. For
// proxies we have to convert as well but also respect the original order.
// Therefore we add a converted key to both sides
if (convert == CONVERT_TO_ARRAY_INDEX || convert == PROXY_MAGIC) {
uint32_t index = 0;
int prev_length = length_;
int prev_proto = level_string_length_;
if ((key->IsString() && Handle<String>::cast(key)->AsArrayIndex(&index)) ||
key->ToArrayIndex(&index)) {
bool key_was_added = AddIntegerKey(index);
if (convert == CONVERT_TO_ARRAY_INDEX) return key_was_added;
if (convert == PROXY_MAGIC) {
// If we had an array index (number) and it wasn't added, the key
// already existed before, hence we cannot add it to the properties
// keys as it would lead to duplicate entries.
if (!key_was_added) {
return false;
}
length_ = prev_length;
level_string_length_ = prev_proto;
}
}
}
return AddStringKey(key, convert);
}
bool KeyAccumulator::AddKey(uint32_t key) { return AddIntegerKey(key); }
bool KeyAccumulator::AddIntegerKey(uint32_t key) {
// Make sure we do not add keys to a proxy-level (see AddKeysFromProxy).
// We mark proxy-levels with a negative length
DCHECK_LE(0, level_string_length_);
// Binary search over all but the last level. The last one might not be
// sorted yet.
for (size_t i = 1; i < elements_.size(); i++) {
if (AccumulatorHasKey(elements_[i - 1], key)) return false;
}
elements_.back()->push_back(key);
length_++;
return true;
}
bool KeyAccumulator::AddStringKey(Handle<Object> key,
AddKeyConversion convert) {
if (string_properties_.is_null()) {
string_properties_ = OrderedHashSet::Allocate(isolate_, 16);
}
// TODO(cbruni): remove this conversion once we throw the correct TypeError
// for non-string/symbol elements returned by proxies
if (convert == PROXY_MAGIC && key->IsNumber()) {
key = isolate_->factory()->NumberToString(key);
}
int prev_size = string_properties_->NumberOfElements();
string_properties_ = OrderedHashSet::Add(string_properties_, key);
if (prev_size < string_properties_->NumberOfElements()) {
length_++;
level_string_length_++;
return true;
} else {
return false;
}
}
bool KeyAccumulator::AddSymbolKey(Handle<Object> key) {
if (symbol_properties_.is_null()) {
symbol_properties_ = OrderedHashSet::Allocate(isolate_, 16);
}
int prev_size = symbol_properties_->NumberOfElements();
symbol_properties_ = OrderedHashSet::Add(symbol_properties_, key);
if (prev_size < symbol_properties_->NumberOfElements()) {
length_++;
level_symbol_length_++;
return true;
} else {
return false;
}
}
void KeyAccumulator::AddKeys(Handle<FixedArray> array,
AddKeyConversion convert) {
int add_length = array->length();
if (add_length == 0) return;
for (int i = 0; i < add_length; i++) {
Handle<Object> current(array->get(i), isolate_);
AddKey(current, convert);
}
}
void KeyAccumulator::AddKeys(Handle<JSObject> array_like,
AddKeyConversion convert) {
DCHECK(array_like->IsJSArray() || array_like->HasSloppyArgumentsElements());
ElementsAccessor* accessor = array_like->GetElementsAccessor();
accessor->AddElementsToKeyAccumulator(array_like, this, convert);
}
void KeyAccumulator::AddKeysFromProxy(Handle<JSObject> array_like) {
// Proxies define a complete list of keys with no distinction of
// elements and properties, which breaks the normal assumption for the
// KeyAccumulator.
AddKeys(array_like, PROXY_MAGIC);
// Invert the current length to indicate a present proxy, so we can ignore
// element keys for this level. Otherwise we would not fully respect the order
// given by the proxy.
level_string_length_ = -level_string_length_;
}
MaybeHandle<FixedArray> FilterProxyKeys(Isolate* isolate, Handle<JSProxy> owner,
Handle<FixedArray> keys,
PropertyFilter filter) {
if (filter == ALL_PROPERTIES) {
// Nothing to do.
return keys;
}
int store_position = 0;
for (int i = 0; i < keys->length(); ++i) {
Handle<Name> key(Name::cast(keys->get(i)), isolate);
if (key->FilterKey(filter)) continue; // Skip this key.
if (filter & ONLY_ENUMERABLE) {
PropertyDescriptor desc;
Maybe<bool> found =
JSProxy::GetOwnPropertyDescriptor(isolate, owner, key, &desc);
MAYBE_RETURN(found, MaybeHandle<FixedArray>());
if (!found.FromJust() || !desc.enumerable()) continue; // Skip this key.
}
// Keep this key.
if (store_position != i) {
keys->set(store_position, *key);
}
store_position++;
}
if (store_position == 0) return isolate->factory()->empty_fixed_array();
keys->Shrink(store_position);
return keys;
}
// Returns "nothing" in case of exception, "true" on success.
Maybe<bool> KeyAccumulator::AddKeysFromProxy(Handle<JSProxy> proxy,
Handle<FixedArray> keys) {
ASSIGN_RETURN_ON_EXCEPTION_VALUE(
isolate_, keys, FilterProxyKeys(isolate_, proxy, keys, filter_),
Nothing<bool>());
// Proxies define a complete list of keys with no distinction of
// elements and properties, which breaks the normal assumption for the
// KeyAccumulator.
AddKeys(keys, PROXY_MAGIC);
// Invert the current length to indicate a present proxy, so we can ignore
// element keys for this level. Otherwise we would not fully respect the order
// given by the proxy.
level_string_length_ = -level_string_length_;
return Just(true);
}
void KeyAccumulator::AddElementKeysFromInterceptor(
Handle<JSObject> array_like) {
AddKeys(array_like, CONVERT_TO_ARRAY_INDEX);
// The interceptor might introduce duplicates for the current level, since
// these keys get added after the objects's normal element keys.
SortCurrentElementsListRemoveDuplicates();
}
void KeyAccumulator::SortCurrentElementsListRemoveDuplicates() {
// Sort and remove duplicates from the current elements level and adjust.
// the lengths accordingly.
auto last_level = elements_.back();
size_t nof_removed_keys = last_level->size();
std::sort(last_level->begin(), last_level->end());
last_level->erase(std::unique(last_level->begin(), last_level->end()),
last_level->end());
// Adjust total length by the number of removed duplicates.
nof_removed_keys -= last_level->size();
length_ -= static_cast<int>(nof_removed_keys);
}
void KeyAccumulator::SortCurrentElementsList() {
if (elements_.empty()) return;
auto element_keys = elements_.back();
std::sort(element_keys->begin(), element_keys->end());
}
void KeyAccumulator::NextPrototype() {
// Store the protoLength on the first call of this method.
if (!elements_.empty()) {
level_lengths_.push_back(level_string_length_);
level_lengths_.push_back(level_symbol_length_);
}
elements_.push_back(new std::vector<uint32_t>());
level_string_length_ = 0;
level_symbol_length_ = 0;
}
} // namespace internal
} // namespace v8