Coverage Report

Created: 2025-08-28 09:57

/src/node/deps/v8/include/v8-container.h
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// Copyright 2021 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef INCLUDE_V8_CONTAINER_H_
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#define INCLUDE_V8_CONTAINER_H_
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#include <stddef.h>
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#include <stdint.h>
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#include <functional>
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#include "v8-local-handle.h"  // NOLINT(build/include_directory)
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#include "v8-object.h"        // NOLINT(build/include_directory)
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#include "v8config.h"         // NOLINT(build/include_directory)
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namespace v8 {
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class Context;
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class Isolate;
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/**
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 * An instance of the built-in array constructor (ECMA-262, 15.4.2).
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 */
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class V8_EXPORT Array : public Object {
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 public:
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  uint32_t Length() const;
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  /**
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   * Creates a JavaScript array with the given length. If the length
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   * is negative the returned array will have length 0.
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   */
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  static Local<Array> New(Isolate* isolate, int length = 0);
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  /**
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   * Creates a JavaScript array out of a Local<Value> array in C++
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   * with a known length.
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   */
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  static Local<Array> New(Isolate* isolate, Local<Value>* elements,
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                          size_t length);
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  V8_INLINE static Array* Cast(Value* value) {
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#ifdef V8_ENABLE_CHECKS
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    CheckCast(value);
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#endif
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    return static_cast<Array*>(value);
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  }
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  /**
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   * Creates a JavaScript array from a provided callback.
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   *
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   * \param context The v8::Context to create the array in.
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   * \param length The length of the array to be created.
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   * \param next_value_callback The callback that is invoked to retrieve
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   *     elements for the array. The embedder can signal that the array
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   *     initialization should be aborted by throwing an exception and returning
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   *     an empty MaybeLocal.
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   * \returns The v8::Array if all elements were constructed successfully and an
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   *     empty MaybeLocal otherwise.
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   */
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  static MaybeLocal<Array> New(
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      Local<Context> context, size_t length,
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      std::function<MaybeLocal<v8::Value>()> next_value_callback);
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  enum class CallbackResult {
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    kException,
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    kBreak,
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    kContinue,
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  };
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  using IterationCallback = CallbackResult (*)(uint32_t index,
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                                               Local<Value> element,
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                                               void* data);
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  /**
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   * Calls {callback} for every element of this array, passing {callback_data}
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   * as its {data} parameter.
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   * This function will typically be faster than calling {Get()} repeatedly.
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   * As a consequence of being optimized for low overhead, the provided
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   * callback must adhere to the following restrictions:
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   *  - It must not allocate any V8 objects and continue iterating; it may
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   *    allocate (e.g. an error message/object) and then immediately terminate
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   *    the iteration.
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   *  - It must not modify the array being iterated.
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   *  - It must not call back into V8 (unless it can guarantee that such a
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   *    call does not violate the above restrictions, which is difficult).
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   *  - The {Local<Value> element} must not "escape", i.e. must not be assigned
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   *    to any other {Local}. Creating a {Global} from it, or updating a
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   *    v8::TypecheckWitness with it, is safe.
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   * These restrictions may be lifted in the future if use cases arise that
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   * justify a slower but more robust implementation.
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   *
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   * Returns {Nothing} on exception; use a {TryCatch} to catch and handle this
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   * exception.
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   * When the {callback} returns {kException}, iteration is terminated
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   * immediately, returning {Nothing}. By returning {kBreak}, the callback
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   * can request non-exceptional early termination of the iteration.
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   */
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  Maybe<void> Iterate(Local<Context> context, IterationCallback callback,
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                      void* callback_data);
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 private:
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  Array();
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  static void CheckCast(Value* obj);
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};
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/**
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 * An instance of the built-in Map constructor (ECMA-262, 6th Edition, 23.1.1).
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 */
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class V8_EXPORT Map : public Object {
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 public:
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  size_t Size() const;
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  void Clear();
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  V8_WARN_UNUSED_RESULT MaybeLocal<Value> Get(Local<Context> context,
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                                              Local<Value> key);
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  V8_WARN_UNUSED_RESULT MaybeLocal<Map> Set(Local<Context> context,
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                                            Local<Value> key,
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                                            Local<Value> value);
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  V8_WARN_UNUSED_RESULT Maybe<bool> Has(Local<Context> context,
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                                        Local<Value> key);
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  V8_WARN_UNUSED_RESULT Maybe<bool> Delete(Local<Context> context,
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                                           Local<Value> key);
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  /**
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   * Returns an array of length Size() * 2, where index N is the Nth key and
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   * index N + 1 is the Nth value.
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   */
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  Local<Array> AsArray() const;
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  /**
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   * Creates a new empty Map.
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   */
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  static Local<Map> New(Isolate* isolate);
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  V8_INLINE static Map* Cast(Value* value) {
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#ifdef V8_ENABLE_CHECKS
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    CheckCast(value);
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#endif
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    return static_cast<Map*>(value);
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  }
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 private:
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  Map();
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  static void CheckCast(Value* obj);
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};
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/**
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 * An instance of the built-in Set constructor (ECMA-262, 6th Edition, 23.2.1).
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 */
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class V8_EXPORT Set : public Object {
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 public:
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  size_t Size() const;
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  void Clear();
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  V8_WARN_UNUSED_RESULT MaybeLocal<Set> Add(Local<Context> context,
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                                            Local<Value> key);
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  V8_WARN_UNUSED_RESULT Maybe<bool> Has(Local<Context> context,
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                                        Local<Value> key);
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  V8_WARN_UNUSED_RESULT Maybe<bool> Delete(Local<Context> context,
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                                           Local<Value> key);
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  /**
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   * Returns an array of the keys in this Set.
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   */
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  Local<Array> AsArray() const;
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  /**
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   * Creates a new empty Set.
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   */
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  static Local<Set> New(Isolate* isolate);
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  V8_INLINE static Set* Cast(Value* value) {
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#ifdef V8_ENABLE_CHECKS
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    CheckCast(value);
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#endif
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    return static_cast<Set*>(value);
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  }
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 private:
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  Set();
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  static void CheckCast(Value* obj);
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};
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}  // namespace v8
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#endif  // INCLUDE_V8_CONTAINER_H_